CI: fix self-hosted runners in Linux builds

Signed-off-by: Delan Azabani <dazabani@igalia.com>

.cargo/config.toml

@@ -34,4 +34,3 @@ RUSTC_BOOTSTRAP = "crown,script,style_tests"
 
 [build]
 rustdocflags = ["--document-private-items"]
-rustc = "crown"

.gitattributes

@@ -1,5 +1,5 @@
 * text=auto eol=lf
-tests/* linguist-vendored
+tests/wpt/** linguist-vendored
 
 # Denote all files that are truly binary and should not be modified.
 *.png binary

.github/CODEOWNERS

@@ -0,0 +1,4 @@
+# Reviewers for the Servo project
+
+
+/components/script/  @gterzian

.github/dependabot.yml

@@ -15,6 +15,15 @@ updates:
          - "glib*"
          - "gobject*"
          - "gstreamer*"
+  groups:
+    egui-related:
+       patterns:
+         - "ecolor"
+         - "egui"
+         - "egui-winit"
+         - "egui_glow"
+         - "emath"
+         - "epaint"
   ignore:
   # Ignore all stylo crates as their upgrades are coordinated via companion PRs.
   - dependency-name: servo_atoms

.github/workflows/android.yml

@@ -30,33 +30,32 @@ jobs:
       matrix:
         arch: ['aarch64-linux-android', 'armv7-linux-androideabi', 'i686-linux-android', 'x86_64-linux-android']
     steps:
+      - name: Free Disk Space (Ubuntu)
+        uses: jlumbroso/free-disk-space@main
+        with:
+          tool-cache: false
+          android: false
+          large-packages: false
+          swap-storage: false
       - uses: actions/checkout@v4
-        if: github.event_name != 'issue_comment' && github.event_name != 'pull_request_target'
+        if: github.event_name != 'pull_request_target'
         with:
           fetch-depth: 2
-      # This is necessary to checkout the pull request if this run was triggered
-      # via an `issue_comment` action on a pull request.
+      # This is necessary to checkout the pull request if this run was triggered via a
+      # `pull_request_target` event.
       - uses: actions/checkout@v4
-        if: github.event_name == 'issue_comment' || github.event_name == 'pull_request_target'
+        if: github.event_name == 'pull_request_target'
         with:
-          ref: refs/pull/${{ github.event.issue.number || github.event.number }}/head
+          ref: ${{ github.event.pull_request.head.sha }}
           fetch-depth: 2
       - name: Run sccache-cache
         uses: mozilla-actions/sccache-action@v0.0.4
-      - name: Install taplo
-        uses: baptiste0928/cargo-install@v3
-        with:
-          crate: taplo-cli
-          locked: true
-      - name: Install cargo-deny
-        uses: baptiste0928/cargo-install@v3
-        with:
-          crate: cargo-deny
-          locked: true
+      - name: Install crown
+        run: cargo install --path support/crown
       - name: Bootstrap Python
         run: python3 -m pip install --upgrade pip virtualenv
       - name: Bootstrap dependencies
-        run: sudo apt update && python3 ./mach bootstrap
+        run: sudo apt update && python3 ./mach bootstrap --skip-lints
       - name: Set up JDK 17
         uses: actions/setup-java@v4
         with:
@@ -70,12 +69,23 @@ jobs:
         uses: nttld/setup-ndk@v1
         id: setup-ndk
         with:
-          ndk-version: r25c
+          ndk-version: r26c
+      - name: Setup Key Store for APK Signing
+        env:
+          KEYSTORE_BASE64: ${{ secrets.APK_KEYSTORE_BASE64 }}
+        if: ${{ env.KEYSTORE_BASE64 != '' }}
+        run: |
+          APK_SIGNING_KEY_STORE_PATH="${PWD}/servo_keystore.jks"
+          echo "${KEYSTORE_BASE64}" | base64 -d > "${APK_SIGNING_KEY_STORE_PATH}"
+          echo "APK_SIGNING_KEY_STORE_PATH=${APK_SIGNING_KEY_STORE_PATH}" >> ${GITHUB_ENV}
       - name: Build (arch ${{ matrix.arch }} profile ${{ inputs.profile }})
         env:
           ANDROID_NDK_ROOT: ${{ steps.setup-ndk.outputs.ndk-path }}
+          APK_SIGNING_KEY_STORE_PASS: ${{ secrets.APK_SIGNING_KEY_STORE_PASS }}
+          APK_SIGNING_KEY_ALIAS: ${{ secrets.APK_SIGNING_KEY_ALIAS }}
+          APK_SIGNING_KEY_PASS: ${{ secrets.APK_SIGNING_KEY_PASS }}
         run: |
-          python3 ./mach build --locked --android --target ${{ matrix.arch }} --${{ inputs.profile }}
+          python3 ./mach build --use-crown --locked --target ${{ matrix.arch }} --${{ inputs.profile }}
           cp -r target/cargo-timings target/cargo-timings-android-${{ matrix.arch }}
       # TODO: This is disabled since APK crashes during startup.
       # See https://github.com/servo/servo/issues/31134

.github/workflows/auto-merge-updates.yml

@@ -0,0 +1,18 @@
+name: Automerge Dependabot & WPT Updates
+on: pull_request
+
+permissions:
+  pull-requests: read
+
+jobs:
+  auto-merge:
+    runs-on: ubuntu-latest
+    if: ${{ github.actor == 'dependabot[bot]' || github.actor == 'servo-wpt-sync' }}
+    steps:
+      - name: Approve the PR & enable auto-merge
+        run: |
+          gh pr review --approve "$PR_URL"
+          gh pr merge --auto --merge "$PR_URL"
+        env:
+          PR_URL: ${{ github.event.pull_request.html_url }}
+          GH_TOKEN: ${{ secrets.SERVO_DEPENDABOT_TOKEN }}

.github/workflows/dco-merge-group.yml

@@ -0,0 +1,12 @@
+# Mostly copied from https://github.com/onnx/onnx/blob/main/.github/workflows/dco_merge_group.yml
+# Because of https://github.com/dcoapp/app/issues/199
+
+name: DCO
+on:
+  merge_group:
+
+jobs:
+  DCO:
+    runs-on: ubuntu-latest
+    steps:
+      - run: echo "dummy DCO workflow (it won't run any check actually) to trigger by merge_group in order to enable merge queue"

.github/workflows/dependabot-pr.yml

@@ -1,22 +0,0 @@
-name: Approve & merge successful dependabot patch upgrade PRs
-on: pull_request
-
-permissions:
-  pull-requests: read
-
-jobs:
-  dependabot:
-    runs-on: ubuntu-latest
-    if: ${{ github.actor == 'dependabot[bot]' }}
-    steps:
-      - name: Dependabot metadata
-        id: metadata
-        uses: dependabot/fetch-metadata@v1
-      - name: Approve the PR & enable auto-merge
-        if: ${{ steps.metadata.outputs.update-type == 'version-update:semver-patch' }}
-        run: |
-          gh pr review --approve "$PR_URL"
-          gh pr merge --auto --merge "$PR_URL"
-        env:
-          PR_URL: ${{github.event.pull_request.html_url}}
-          GH_TOKEN: ${{secrets.SERVO_DEPENDABOT_TOKEN}}

.github/workflows/dispatch-workflow.yml

@@ -8,7 +8,7 @@ on:
       profile:
         required: true
         type: string
-      wpt-tests-to-run:
+      wpt-args:
         required: true
         type: string
       wpt-layout:
@@ -37,7 +37,7 @@ jobs:
       profile: ${{ inputs.profile }}
       wpt-layout: ${{ inputs.wpt-layout }}
       unit-tests: ${{ inputs.unit-tests }}
-      wpt-tests-to-run: ${{ inputs.wpt-tests-to-run }}
+      wpt-args: ${{ inputs.wpt-args }}
 
   linux:
     if: ${{ inputs.workflow == 'linux' }}
@@ -48,7 +48,13 @@ jobs:
       profile: ${{ inputs.profile }}
       wpt-layout: ${{ inputs.wpt-layout }}
       unit-tests: ${{ inputs.unit-tests }}
-      wpt-tests-to-run: ${{ inputs.wpt-tests-to-run }}
+      wpt-args: ${{ inputs.wpt-args }}
+
+  lint:
+    if: ${{ inputs.workflow == 'lint' }}
+    name: Lint
+    uses: ./.github/workflows/lint.yml
+    secrets: inherit
 
   android:
     if: ${{ inputs.workflow == 'android' }}

.github/workflows/docs.yml

@@ -17,7 +17,7 @@ jobs:
         run: |
           python3 -m pip install --upgrade pip
           sudo apt update
-          python3 ./mach bootstrap
+          python3 ./mach bootstrap --skip-lints
       - name: Set LIBCLANG_PATH # This is needed for bindgen in mozangle.
         run: echo "LIBCLANG_PATH=/usr/lib/llvm-14/lib" >> $GITHUB_ENV
       - name: Compile docs

.github/workflows/lint.yml

@@ -0,0 +1,59 @@
+name: Lint
+on:
+  workflow_call:
+  workflow_dispatch:
+
+env:
+  RUST_BACKTRACE: 1
+  SHELL: /bin/bash
+  SCCACHE_GHA_ENABLED: "true"
+  RUSTC_WRAPPER: "sccache"
+  CCACHE: "sccache"
+  CARGO_INCREMENTAL: 0
+
+jobs:
+  lint:
+    name: Lint
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+        if: github.event_name != 'pull_request_target'
+        with:
+          fetch-depth: 2 # This is necessary for `test-tidy`.
+      # This is necessary to checkout the pull request if this run was triggered via a
+      # `pull_request_target` event.
+      - uses: actions/checkout@v4
+        if: github.event_name == 'pull_request_target'
+        with:
+          ref: ${{ github.event.pull_request.head.sha }}
+          fetch-depth: 2 # This is necessary for `test-tidy`.
+      - name: Run sccache-cache
+        uses: mozilla-actions/sccache-action@v0.0.4
+      - name: Set LIBCLANG_PATH env # needed for bindgen in mozangle
+        run: echo "LIBCLANG_PATH=/usr/lib/llvm-14/lib" >> $GITHUB_ENV
+      - uses: actions/setup-python@v5
+        with:
+          python-version: '3.10'
+      - name: Install taplo
+        uses: baptiste0928/cargo-install@v3
+        with:
+          crate: taplo-cli
+          locked: true
+      - name: Install cargo-deny
+        uses: baptiste0928/cargo-install@v3
+        with:
+          crate: cargo-deny
+          locked: true
+      - name: Bootstrap Python
+        run: python3 -m pip install --upgrade pip
+      - name: Bootstrap dependencies
+        run: |
+          sudo apt update
+          python3 ./mach bootstrap
+      # TODO: Do GitHub anotaions
+      # TODO: Fail on warnings
+      - name: Clippy
+        run: |
+          python3 ./mach cargo-clippy --use-crown --locked
+      - name: Tidy
+        run: python3 ./mach test-tidy --no-progress --all

.github/workflows/linux-wpt.yml

@@ -5,7 +5,7 @@ on:
       profile:
         required: true
         type: string
-      wpt-tests-to-run:
+      wpt-args:
         default: ""
         required: false
         type: string
@@ -55,7 +55,7 @@ jobs:
           python3 -m pip install --upgrade pip
           sudo apt update
           sudo apt install -qy --no-install-recommends mesa-vulkan-drivers
-          python3 ./mach bootstrap
+          python3 ./mach bootstrap --skip-lints
       - name: Sync from upstream WPT
         if: ${{ inputs.wpt-sync-from-upstream }}
         run: |
@@ -67,13 +67,13 @@ jobs:
           python3 ./mach test-wpt \
             $WPT_LAYOUT_ARG \
             $WPT_ALWAYS_SUCCEED_ARG \
-            ${{ inputs.wpt-tests-to-run }} \
             --${{ inputs.profile }} --processes $(nproc) --timeout-multiplier 2 \
             --total-chunks ${{ env.max_chunk_id }} --this-chunk ${{ matrix.chunk_id }} \
             --log-raw wpt-full-logs/linux-${{ inputs.wpt-layout }}/raw/${{ matrix.chunk_id }}.log \
             --log-wptreport wpt-full-logs/linux-${{ inputs.wpt-layout }}/wptreport/${{ matrix.chunk_id }}.json \
             --log-raw-unexpected wpt-filtered-logs/linux-${{ inputs.wpt-layout }}/${{ matrix.chunk_id }}.log \
-            --filter-intermittents wpt-filtered-logs/linux-${{ inputs.wpt-layout }}/${{ matrix.chunk_id }}.json
+            --filter-intermittents wpt-filtered-logs/linux-${{ inputs.wpt-layout }}/${{ matrix.chunk_id }}.json \
+            ${{ inputs.wpt-args }}
         env:
           GITHUB_CONTEXT: ${{ toJson(github) }}
       - name: Archive results (filtered)

.github/workflows/linux.yml

@@ -6,7 +6,7 @@ on:
         required: false
         default: "release"
         type: string
-      wpt-tests-to-run:
+      wpt-args:
         default: ""
         required: false
         type: string
@@ -35,7 +35,7 @@ on:
         default: "release"
         type: choice
         options: ["release", "debug", "production"]
-      wpt-tests-to-run:
+      wpt-args:
         default: ""
         required: false
         type: string
@@ -59,59 +59,92 @@ on:
 env:
   RUST_BACKTRACE: 1
   SHELL: /bin/bash
-  SCCACHE_GHA_ENABLED: "true"
-  RUSTC_WRAPPER: "sccache"
-  CCACHE: "sccache"
-  CARGO_INCREMENTAL: 0
 
 jobs:
+  # Runs the underlying job (“workload”) on a self-hosted runner if available,
+  # with the help of a `runner-select` job and a `runner-timeout` job.
+  runner-select:
+    uses: ./.github/workflows/self-hosted-runner-select.yml
+    secrets: inherit
+    with:
+      # Ubuntu 22.04 has glibc 2.34 so the binaries produced
+      # won't run on systems with older glibc e.g wpt.fyi
+      # runners which still use 20.04.
+      github-hosted-runner-label: ubuntu-${{ inputs.upload && '20.04' || '22.04' }}
+      self-hosted-image-name: servo-ubuntu2204
+      force-github-hosted-runner: ${{ inputs.upload }}
+  runner-timeout:
+    needs:
+      - runner-select
+    uses: ./.github/workflows/self-hosted-runner-timeout.yml
+    secrets: inherit
+    with:
+      selected-runner-label: ${{ needs.runner-select.outputs.selected-runner-label }}
+      is-self-hosted: ${{ fromJSON(needs.runner-select.outputs.is-self-hosted) }}
+
   build:
-    name: Linux Build
-    # Ubuntu 22.04 has glibc 2.34 so the binaries produced
-    # won't run on systems with older glibc e.g wpt.fyi
-    # runners which still use 20.04.
-    runs-on: ubuntu-${{ inputs.upload && '20.04' || '22.04' }}
+    needs:
+      - runner-select
+    name: Linux Build [${{ needs.runner-select.outputs.unique-id }}]
+    runs-on: ${{ needs.runner-select.outputs.selected-runner-label }}
     steps:
+      - if: ${{ ! fromJSON(needs.runner-select.outputs.is-self-hosted) }}
+        run: |
+          echo SCCACHE_GHA_ENABLED=true >> $GITHUB_ENV
+          echo RUSTC_WRAPPER=sccache >> $GITHUB_ENV
+          echo CCACHE=sccache >> $GITHUB_ENV
+          echo CARGO_INCREMENTAL=0 >> $GITHUB_ENV
+
       - uses: actions/checkout@v4
-        if: github.event_name != 'pull_request_target'
-        with:
-          fetch-depth: 2 # This is necessary for `test-tidy`.
+        if: ${{ ! fromJSON(needs.runner-select.outputs.is-self-hosted) && github.event_name != 'pull_request_target' }}
       # This is necessary to checkout the pull request if this run was triggered via a
       # `pull_request_target` event.
       - uses: actions/checkout@v4
-        if: github.event_name == 'pull_request_target'
+        if: ${{ ! fromJSON(needs.runner-select.outputs.is-self-hosted) && github.event_name == 'pull_request_target' }}
         with:
-          ref: refs/pull/${{ github.event.number }}/head
-          fetch-depth: 2 # This is necessary for `test-tidy`.
+          ref: ${{ github.event.pull_request.head.sha }}
+
+      # Faster checkout for self-hosted runner that uses prebaked repo.
+      - if: ${{ fromJSON(needs.runner-select.outputs.is-self-hosted) && github.event_name != 'pull_request_target' }}
+        run: git fetch --depth=1 origin $GITHUB_SHA
+      - if: ${{ fromJSON(needs.runner-select.outputs.is-self-hosted) && github.event_name == 'pull_request_target' }}
+        run: git fetch --depth=1 origin ${{ github.event.pull_request.head.sha }}
+      - if: ${{ fromJSON(needs.runner-select.outputs.is-self-hosted) }}
+        # Same as `git switch --detach FETCH_HEAD`, but fixes up dirty working
+        # trees, in case the runner image was baked with a dirty working tree.
+        run: |
+          git switch --detach
+          git reset --hard FETCH_HEAD
+
+      # Install missing tools in a GitHub-hosted runner.
       - name: Run sccache-cache
+        if: ${{ ! fromJSON(needs.runner-select.outputs.is-self-hosted) }}
         uses: mozilla-actions/sccache-action@v0.0.4
       - name: Set LIBCLANG_PATH env # needed for bindgen in mozangle
-        if: ${{ !inputs.upload  }} # not needed on ubuntu 20.04 used for nightly
+        if: ${{ ! fromJSON(needs.runner-select.outputs.is-self-hosted) && !inputs.upload }} # not needed on ubuntu 20.04 used for nightly
         run: echo "LIBCLANG_PATH=/usr/lib/llvm-14/lib" >> $GITHUB_ENV
       - uses: actions/setup-python@v5
+        if: ${{ ! fromJSON(needs.runner-select.outputs.is-self-hosted) }}
         with:
           python-version: '3.10'
-      - name: Install taplo
-        uses: baptiste0928/cargo-install@v3
-        with:
-          crate: taplo-cli
-          locked: true
-      - name: Install cargo-deny
-        uses: baptiste0928/cargo-install@v3
-        with:
-          crate: cargo-deny
-          locked: true
       - name: Bootstrap Python
+        if: ${{ ! fromJSON(needs.runner-select.outputs.is-self-hosted) }}
         run: python3 -m pip install --upgrade pip
       - name: Bootstrap dependencies
+        if: ${{ ! fromJSON(needs.runner-select.outputs.is-self-hosted) }}
         run: |
           sudo apt update
-          python3 ./mach bootstrap
-      - name: Tidy
-        run: python3 ./mach test-tidy --no-progress --all
+          python3 ./mach bootstrap --skip-lints
+
+      # Always install crown, even on self-hosted runners, because it is tightly
+      # coupled to the rustc version, and we may have the wrong version if the
+      # commit we are building uses a different rustc version.
+      - name: Install crown
+        run: cargo install --path support/crown
+
       - name: Build (${{ inputs.profile }})
         run: |
-          python3 ./mach build --locked --${{ inputs.profile }}
+          python3 ./mach build --use-crown --locked --${{ inputs.profile }}
           cp -r target/cargo-timings target/cargo-timings-linux
       - name: Smoketest
         run: xvfb-run python3 ./mach smoketest --${{ inputs.profile  }}
@@ -161,7 +194,7 @@ jobs:
     needs: ["build"]
     uses: ./.github/workflows/linux-wpt.yml
     with:
-      wpt-tests-to-run: ${{ inputs.wpt-tests-to-run }}
+      wpt-args: ${{ inputs.wpt-args }}
       profile: ${{ inputs.profile }}
       wpt-sync-from-upstream: ${{ inputs.wpt-sync-from-upstream }}
       wpt-layout: "layout-2020"
@@ -173,7 +206,7 @@ jobs:
     needs: ["build"]
     uses: ./.github/workflows/linux-wpt.yml
     with:
-      wpt-tests-to-run: ${{ inputs.wpt-tests-to-run }}
+      wpt-args: ${{ inputs.wpt-args }}
       profile: ${{ inputs.profile }}
       wpt-sync-from-upstream: ${{ inputs.wpt-sync-from-upstream }}
       wpt-layout: "layout-2013"

.github/workflows/mac-wpt.yml

@@ -3,7 +3,7 @@ name: Mac WPT Tests
 on:
   workflow_call:
     inputs:
-      wpt-tests-to-run:
+      wpt-args:
         default: ""
         required: false
         type: string
@@ -45,19 +45,20 @@ jobs:
         run: |
           gtar -xzf target.tar.gz
           python3 -m pip install --upgrade pip
-          python3 ./mach bootstrap
+          python3 ./mach bootstrap --skip-lints
       - name: Smoketest
         run: python3 ./mach smoketest --${{ inputs.profile }}
       - name: Run tests
         run: |
           mkdir -p wpt-filtered-logs/macos-${{ inputs.wpt-layout }}
           mkdir -p wpt-full-logs/macos-${{ inputs.wpt-layout }}
-          python3 ./mach test-wpt $WPT_COMMAND_LINE_ARG ${{ inputs.wpt-tests-to-run }} \
+          python3 ./mach test-wpt $WPT_COMMAND_LINE_ARG \
             --${{ inputs.profile }} --processes $(sysctl -n hw.logicalcpu) --timeout-multiplier 8 \
             --total-chunks ${{ env.max_chunk_id }} --this-chunk ${{ matrix.chunk_id }} \
             --log-raw wpt-full-logs/macos-${{ inputs.wpt-layout }}/${{ matrix.chunk_id }}.log \
             --log-raw-unexpected wpt-filtered-logs/macos-${{ inputs.wpt-layout }}/${{ matrix.chunk_id }}.log \
             --filter-intermittents wpt-filtered-logs/macos-${{ inputs.wpt-layout }}/${{ matrix.chunk_id }}.json
+            ${{ inputs.wpt-args }}
       - name: Archive results (filtered)
         uses: actions/upload-artifact@v4
         if: ${{ always() }}

.github/workflows/mac.yml

@@ -7,7 +7,7 @@ on:
         required: false
         default: "release"
         type: string
-      wpt-tests-to-run:
+      wpt-args:
         default: ""
         required: false
         type: string
@@ -32,7 +32,7 @@ on:
         default: "release"
         type: choice
         options: ["release", "debug", "production"]
-      wpt-tests-to-run:
+      wpt-args:
         default: ""
         required: false
         type: string
@@ -76,27 +76,19 @@ jobs:
       - uses: actions/checkout@v4
         if: github.event_name == 'pull_request_target'
         with:
-          ref: refs/pull/${{ github.event.number }}/head
+          ref: ${{ github.event.pull_request.head.sha }}
       - name: Run sccache-cache
         uses: mozilla-actions/sccache-action@v0.0.4
-      - name: Install taplo
-        uses: baptiste0928/cargo-install@v3
-        with:
-          crate: taplo-cli
-          locked: true
-      - name: Install cargo-deny
-        uses: baptiste0928/cargo-install@v3
-        with:
-          crate: cargo-deny
-          locked: true
+      - name: Install crown
+        run: cargo install --path support/crown
       - name: Bootstrap
         run: |
           python3 -m pip install --upgrade pip
-          python3 ./mach bootstrap
+          python3 ./mach bootstrap --skip-lints
           brew install gnu-tar
       - name: Build (${{ inputs.profile }})
         run: |
-          python3 ./mach build --locked --${{ inputs.profile }}
+          python3 ./mach build --use-crown --locked --${{ inputs.profile }}
           cp -r target/cargo-timings target/cargo-timings-macos
       - name: Smoketest
         uses: nick-fields/retry@v3
@@ -158,7 +150,7 @@ jobs:
     with:
       profile: ${{ inputs.profile }}
       wpt-layout: "layout-2020"
-      wpt-tests-to-run: ${{ inputs.wpt-tests-to-run }}
+      wpt-args: ${{ inputs.wpt-args }}
     secrets: inherit
 
   wpt-2013:
@@ -169,5 +161,5 @@ jobs:
     with:
       profile: ${{ inputs.profile }}
       wpt-layout: "layout-2013"
-      wpt-tests-to-run: ${{ inputs.wpt-tests-to-run }}
+      wpt-args: ${{ inputs.wpt-args }}
     secrets: inherit

.github/workflows/main.yml

@@ -38,6 +38,11 @@ jobs:
       wpt-layout: ${{ github.event_name == 'pull_request' && 'none' || '2020' }}
     secrets: inherit
 
+  lint:
+    name: Lint
+    uses: ./.github/workflows/lint.yml
+    secrets: inherit
+
   build-android:
     name: Android
     if: ${{ github.event_name != 'pull_request' }}
@@ -64,6 +69,7 @@ jobs:
       - "build-linux"
       - "build-android"
       - "build-ohos"
+      - "lint"
     steps:
       - name: Merge build timings
         uses: actions/upload-artifact/merge@v4

.github/workflows/ohos.yml

@@ -29,35 +29,27 @@ jobs:
     runs-on: ubuntu-22.04
     strategy:
       matrix:
-        arch: ['aarch64-unknown-linux-ohos']
+        arch: ['aarch64-unknown-linux-ohos', 'x86_64-unknown-linux-ohos']
     steps:
       - uses: actions/checkout@v4
-        if: github.event_name != 'issue_comment' && github.event_name != 'pull_request_target'
+        if: github.event_name != 'pull_request_target'
         with:
           fetch-depth: 2
-      # This is necessary to checkout the pull request if this run was triggered
-      # via an `issue_comment` action on a pull request.
+      # This is necessary to checkout the pull request if this run was triggered via a
+      # `pull_request_target` event.
       - uses: actions/checkout@v4
-        if: github.event_name == 'issue_comment' || github.event_name == 'pull_request_target'
+        if: github.event_name == 'pull_request_target'
         with:
-          ref: refs/pull/${{ github.event.issue.number || github.event.number }}/head
+          ref: ${{ github.event.pull_request.head.sha }}
           fetch-depth: 2
       - name: Run sccache-cache
         uses: mozilla-actions/sccache-action@v0.0.4
-      - name: Install taplo
-        uses: baptiste0928/cargo-install@v3
-        with:
-          crate: taplo-cli
-          locked: true
-      - name: Install cargo-deny
-        uses: baptiste0928/cargo-install@v3
-        with:
-          crate: cargo-deny
-          locked: true
+      - name: Install crown
+        run: cargo install --path support/crown
       - name: Bootstrap Python
         run: python3 -m pip install --upgrade pip virtualenv
       - name: Bootstrap dependencies
-        run: sudo apt update && python3 ./mach bootstrap
+        run: sudo apt update && python3 ./mach bootstrap --skip-lints
       - name: Setup OpenHarmony SDK
         id: setup_sdk
         uses: openharmony-rs/setup-ohos-sdk@v0.1

.github/workflows/pull-request-wpt-export.yml

@@ -2,6 +2,7 @@ name: WPT Export
 on:
   pull_request_target:
     types: ['opened', 'synchronize', 'reopened', 'edited', 'closed']
+    branches: ['main']
 
 jobs:
   upstream:

.github/workflows/quick-check.yml

@@ -1,16 +0,0 @@
-# This action is meant as a quick check to be run when pushing to
-# branches on forks. This allows forks to test the build and unit
-# tests automatically without opening a pull request.
-name: Quick check
-on:
-  push:
-    branches-ignore:
-      ["main", "auto", "try", "try-*", "dependabot/**"]
-
-jobs:
-  build-linux:
-    name: Linux
-    if: github.repository != 'servo/servo' || github.event_name == 'workflow_dispatch'
-    uses: ./.github/workflows/linux.yml
-    with:
-      unit-tests: true

.github/workflows/self-hosted-runner-select.yml

@@ -0,0 +1,98 @@
+name: Select Self-hosted Runner
+on:
+  workflow_call:
+    inputs:
+      github-hosted-runner-label:
+        required: true
+        type: string
+      self-hosted-image-name:
+        required: true
+        type: string
+      self-hosted-runner-scope:
+        required: false
+        type: string
+        default: /orgs/${{ github.repository_owner }}/actions/runners
+      monitor-api-base-url:
+        required: false
+        type: string
+        default: https://ci0.servo.org
+      force-github-hosted-runner:
+        required: false
+        type: boolean
+        default: false
+    outputs:
+      unique-id:
+        value: ${{ jobs.runner-select.outputs.unique-id }}
+      selected-runner-label:
+        value: ${{ jobs.runner-select.outputs.selected-runner-label }}
+      is-self-hosted:
+        value: ${{ jobs.runner-select.outputs.is-self-hosted }}
+
+jobs:
+  # Selects a self-hosted runner if available, or else a GitHub-hosted runner.
+  # We generate a unique id for the workload, then ask our monitor API to
+  # reserve a self-hosted runner for us.
+  runner-select:
+    name: Select Runner
+    runs-on: ubuntu-latest
+    outputs:
+      unique-id: ${{ steps.select.outputs.unique_id }}
+      selected-runner-label: ${{ steps.select.outputs.selected_runner_label }}
+      is-self-hosted: ${{ steps.select.outputs.is_self_hosted }}
+    steps:
+      - name: Select and reserve best available runner
+        id: select
+        run: |
+          github_hosted_runner_label='${{ inputs.github-hosted-runner-label }}'
+          self_hosted_image_name='${{ inputs.self-hosted-image-name }}'
+          self_hosted_runner_scope='${{ inputs.self-hosted-runner-scope }}'
+          monitor_api_base_url='${{ inputs.monitor-api-base-url }}'
+
+          set -euo pipefail
+
+          fall_back_to_github_hosted() {
+            echo 'Falling back to GitHub-hosted runner'
+            echo "selected_runner_label=$github_hosted_runner_label" | tee -a $GITHUB_OUTPUT
+            echo 'is_self_hosted=false' | tee -a $GITHUB_OUTPUT
+            exit 0
+          }
+
+          # Generate a unique id that allows the workload job to find the runner
+          # we are reserving for it (via runner labels), and allows the timeout
+          # job to find the workload job run (via the job’s friendly name), even
+          # if there are multiple instances in the workflow call tree.
+          unique_id=$(uuidgen)
+          echo "unique_id=$unique_id" | tee -a $GITHUB_OUTPUT
+
+          # Disable self-hosted runners by creating a repository variable named
+          # NO_SELF_HOSTED_RUNNERS with any non-empty value.
+          # <https://github.com/servo/servo/settings/variables/actions>
+          if [ -n '${{ vars.NO_SELF_HOSTED_RUNNERS }}' ]; then
+            echo 'NO_SELF_HOSTED_RUNNERS is set!'
+            # fall_back_to_github_hosted
+          fi
+
+          if [ '${{ inputs.force-github-hosted-runner }}' = true ]; then
+            echo 'inputs.force-github-hosted-runner is set!'
+            fall_back_to_github_hosted
+          fi
+
+          # Use the monitor API to reserve a runner. If we get an object with
+          # runner details, we succeeded. If we get null, we failed.
+          take_runner_url=$monitor_api_base_url/$self_hosted_image_name/$unique_id/${{ github.repository }}/${{ github.run_id }}
+          result=$(mktemp)
+          echo
+          echo POST "$take_runner_url"
+          if ! curl -sS --fail-with-body --connect-timeout 5 --max-time 30 -X POST "$take_runner_url" \
+              -H 'Authorization: Bearer ${{ secrets.SERVO_CI_MONITOR_API_TOKEN }}' > $result \
+              || ! jq -e . $result > /dev/null; then
+            cat $result
+            echo
+            echo
+            echo 'No self-hosted runners available!'
+            fall_back_to_github_hosted
+          fi
+
+          echo
+          echo "selected_runner_label=reserved-for:$unique_id" | tee -a $GITHUB_OUTPUT
+          echo 'is_self_hosted=true' | tee -a $GITHUB_OUTPUT

.github/workflows/self-hosted-runner-timeout.yml

@@ -0,0 +1,39 @@
+name: Detect Self-hosted Runner Timeout
+on:
+  workflow_call:
+    inputs:
+      selected-runner-label:
+        required: true
+        type: string
+      is-self-hosted:
+        required: true
+        type: boolean
+
+jobs:
+  # In the unlikely event a self-hosted runner was selected and reserved but it
+  # goes down before the workload starts, cancel the workflow run.
+  runner-timeout:
+    if: ${{ inputs.is-self-hosted }}
+    name: Detect Runner Timeout
+    runs-on: ubuntu-latest
+    steps:
+      - name: Wait a bit
+        run: sleep 30
+
+      - name: Cancel if workload job is still queued
+        run: |
+          run_url=/repos/${{ github.repository }}/actions/runs/${{ github.run_id }}
+          export GH_TOKEN=${{ secrets.GITHUB_TOKEN }}
+
+          if [ "$(gh api "$run_url/jobs" \
+            | jq -er --arg id '${{ inputs.unique-id }}' \
+              '.jobs[] | select(.name | contains("[" + $id + "]")) | .status'
+          )" = queued ]; then
+            echo 'Timeout waiting for runner assignment!'
+            echo 'Hint: does this repo have permission to access the runner group?'
+            echo 'Hint: https://github.com/organizations/servo/settings/actions/runner-groups'
+            echo
+            echo 'Cancelling workflow run'
+            gh api "$run_url/cancel" --method POST
+            exit 1
+          fi

.github/workflows/try-label.yml

@@ -82,9 +82,6 @@ jobs:
           python-version: '3.10'
       - uses: actions/checkout@v4
         with:
-          # This is necessary to checkout the pull request if this run was triggered
-          # via an `label` action on a pull request.
-          ref: refs/pull/${{ github.event.number }}/head
           sparse-checkout: |
             python/servo/try_parser.py
           sparse-checkout-cone-mode: false
@@ -139,7 +136,7 @@ jobs:
       wpt-layout: ${{ matrix.wpt_layout }}
       profile: ${{ matrix.profile }}
       unit-tests: ${{ matrix.unit_tests }}
-      wpt-tests-to-run: ${{ matrix.wpt_tests_to_run }}
+      wpt-args: ${{ matrix.wpt_args }}
 
   results:
     name: Results

.github/workflows/try.yml

@@ -10,7 +10,7 @@ on:
         default: "release"
         type: choice
         options: ["release", "debug", "production"]
-      wpt-tests-to-run:
+      wpt-args:
         default: ""
         required: false
         type: string
@@ -75,7 +75,7 @@ jobs:
             if (context.eventName == "workflow_dispatch") {
               // WPT-related overrides only affect Linux currently, as tests don't run by default on other platforms.
               configuration.matrix[0].wpt_layout = "${{ inputs.wpt-layout }}" || "none";
-              configuration.matrix[0].wpt_tests_to_run = "${{ inputs.wpt-tests-to-run }}" || "";
+              configuration.matrix[0].wpt_args = "${{ inputs.wpt-args }}" || "";
 
               let unit_tests = Boolean(${{ inputs.unit-tests }});
               let profile = '${{ inputs.profile }}';
@@ -103,7 +103,7 @@ jobs:
       wpt-layout: ${{ matrix.wpt_layout }}
       profile: ${{ matrix.profile }}
       unit-tests: ${{ matrix.unit_tests }}
-      wpt-tests-to-run: ${{ matrix.wpt_tests_to_run }}
+      wpt-args: ${{ matrix.wpt_args }}
 
   build-result:
     name: Result
@@ -113,6 +113,7 @@ jobs:
     needs: [ "decision", "build" ]
     steps:
       - name: Merge build timings
+        continue-on-error: true
         uses: actions/upload-artifact/merge@v4
         with:
           name: cargo-timings

.github/workflows/windows.yml

@@ -42,61 +42,105 @@ env:
   # clang_sys will search msys path before Program Files\LLVM
   # so we need to override this behaviour until we update clang-sys
   # https://github.com/KyleMayes/clang-sys/issues/150
-  LIBCLANG_PATH: C:\\Program Files\\LLVM\\bin
+  LIBCLANG_PATH: C:\Program Files\LLVM\bin
   RUSTUP_WINDOWS_PATH_ADD_BIN: 1
 
 jobs:
+  # Runs the underlying job (“workload”) on a self-hosted runner if available,
+  # with the help of a `runner-select` job and a `runner-timeout` job.
+  runner-select:
+    uses: ./.github/workflows/self-hosted-runner-select.yml
+    secrets: inherit
+    with:
+      github-hosted-runner-label: windows-2022
+      self-hosted-image-name: servo-windows10
+  runner-timeout:
+    needs:
+      - runner-select
+    uses: ./.github/workflows/self-hosted-runner-timeout.yml
+    secrets: inherit
+    with:
+      selected-runner-label: ${{ needs.runner-select.outputs.selected-runner-label }}
+      is-self-hosted: ${{ fromJSON(needs.runner-select.outputs.is-self-hosted) }}
+
   build:
-    name: Windows Build
-    runs-on: windows-2022
+    needs:
+      - runner-select
+    name: Windows Build [${{ needs.runner-select.outputs.unique-id }}]
+    runs-on: ${{ needs.runner-select.outputs.selected-runner-label }}
     steps:
-      - uses: actions/checkout@v4
-        if: github.event_name != 'pull_request_target'
-      # This is necessary to checkout the pull request if this run was triggered via a
-      # `pull_request_target` event.
-      - uses: actions/checkout@v4
-        if: github.event_name == 'pull_request_target'
+      - if: ${{ ! fromJSON(needs.runner-select.outputs.is-self-hosted) && github.event_name != 'pull_request_target' }}
+        uses: actions/checkout@v4
+      - if: ${{ ! fromJSON(needs.runner-select.outputs.is-self-hosted) && github.event_name == 'pull_request_target' }}
+        uses: actions/checkout@v4
         with:
-          ref: refs/pull/${{ github.event.number }}/head
-          fetch-depth: 2
+          ref: ${{ github.event.pull_request.head.sha }}
+          fetch-depth: 1
+
+      # Faster checkout for self-hosted runner that uses prebaked repo.
+      - if: ${{ fromJSON(needs.runner-select.outputs.is-self-hosted) && github.event_name != 'pull_request_target' }}
+        run: git fetch --depth=1 origin $env:GITHUB_SHA
+      - if: ${{ fromJSON(needs.runner-select.outputs.is-self-hosted) && github.event_name == 'pull_request_target' }}
+        run: git fetch --depth=1 origin ${{ github.event.pull_request.head.sha }}
+      - if: ${{ fromJSON(needs.runner-select.outputs.is-self-hosted) }}
+        # Same as `git switch --detach FETCH_HEAD`, but fixes up dirty working
+        # trees, in case the runner image was baked with a dirty working tree.
+        run: |
+          git switch --detach
+          git reset --hard FETCH_HEAD
+
+      - name: ccache
+        # FIXME: “Error: Restoring cache failed: Error: Unable to locate executable file: sh.”
+        if: ${{ ! fromJSON(needs.runner-select.outputs.is-self-hosted) }}
+        uses: hendrikmuhs/ccache-action@v1.2
+
+      # Install missing tools in a GitHub-hosted runner.
       # Workaround for https://github.com/actions/runner-images/issues/10001:
       - name: Upgrade llvm
+        if: ${{ ! fromJSON(needs.runner-select.outputs.is-self-hosted) }}
         run: choco upgrade llvm
-      - name: ccache
-        uses: hendrikmuhs/ccache-action@v1.2
-      - name: Install taplo
-        uses: baptiste0928/cargo-install@v3
-        with:
-          crate: taplo-cli
-          locked: true
-      - name: Install cargo-deny
-        uses: baptiste0928/cargo-install@v3
-        with:
-          crate: cargo-deny
-          locked: true
       - name: Install wixtoolset
+        if: ${{ ! fromJSON(needs.runner-select.outputs.is-self-hosted) }}
         run: |
           choco install wixtoolset
           echo "C:\\Program Files (x86)\\WiX Toolset v3.11\\bin" | Out-File -FilePath $env:GITHUB_PATH -Encoding utf8 -Append
       - uses: actions/setup-python@v5
+        if: ${{ ! fromJSON(needs.runner-select.outputs.is-self-hosted) }}
         with:
           python-version: "3.10"
       - name: Bootstrap
+        if: ${{ ! fromJSON(needs.runner-select.outputs.is-self-hosted) }}
         run: |
           python -m pip install --upgrade pip
           python mach fetch
           python mach bootstrap-gstreamer
-          cargo install --path support/crown
       # For some reason WiX isn't currently on the GitHub runner path. This is a
       # temporary workaround until that is fixed.
       - name: Add WiX to Path
+        if: ${{ ! fromJSON(needs.runner-select.outputs.is-self-hosted) }}
         run: |
           "$env:WIX\bin" >> $env:GITHUB_PATH
+
+      # Always install crown, even on self-hosted runners, because it is tightly
+      # coupled to the rustc version, and we may have the wrong version if the
+      # commit we are building uses a different rustc version.
+      - name: Install crown
+        run: cargo install --path support/crown --force
+
+      - name: Debug logging for incremental builds
+        if: ${{ fromJSON(needs.runner-select.outputs.is-self-hosted) }}
+        run: |
+          cat C:\init\incremental_build_debug.txt
+          echo "`$env:LIBCLANG_PATH now = $env:LIBCLANG_PATH"
+          echo "`$env:PATH now = $env:PATH"
+
       - name: Build (${{ inputs.profile }})
         run: |
-          python mach build --locked --${{ inputs.profile }}
+          python mach build --use-crown --locked --${{ inputs.profile }}
           cp C:\a\servo\servo\target\cargo-timings C:\a\servo\servo\target\cargo-timings-windows -Recurse
       - name: Copy resources
+        if: ${{ ! fromJSON(needs.runner-select.outputs.is-self-hosted) }}
+        # GitHub-hosted runners check out the repo on D: drive.
         run: cp D:\a\servo\servo\resources C:\a\servo\servo -Recurse
       - name: Smoketest
         run: python mach smoketest --${{ inputs.profile }}

.gitignore

@@ -12,6 +12,7 @@
 /python/_venv*
 /python/tidy/servo_tidy.egg-info
 /tests/wpt/sync
+/tests/dromaeo/dromaeo
 *.pkl
 *.pyc
 *.swp
@@ -22,9 +23,10 @@
 .coverage
 .DS_Store
 Servo.app
+servo.pftrace
 .config.mk.last
 /glfw
-capture_webrender/
+webrender-captures/
 /screenshots
 
 # Allow CSV files to be used as resources in tests

CODE_OF_CONDUCT.md

@@ -1,6 +1,6 @@
 # Code of Conduct
 
-The Servo Project follows the [**Rust Code of Conduct**](https://www.rust-lang.org/policies/code-of-conduct), with two differences.
+The Servo Project follows the [**Rust Code of Conduct**](https://www.rust-lang.org/policies/code-of-conduct), with the differences below.
 
 Our code of conduct applies to the [Servo Zulip channels](https://servo.zulipchat.com/), [GitHub repositories](https://github.com/servo), and all official Servo venues, rather than the Rust project.
 

CONTRIBUTING.md

@@ -1,78 +1,5 @@
 # Contributing to Servo
 
-Servo welcomes contribution from everyone. Here are the guidelines if you are
-thinking of helping us:
-
-
-## Contributions
-
-Contributions to Servo or its dependencies should be made in the form of GitHub
-pull requests. Each pull request will be reviewed by a core contributor
-(someone with permission to land patches) and either landed in the main tree or
-given feedback for changes that would be required. All contributions should
-follow this format, even those from core contributors.
-
-Should you wish to work on an issue, please claim it first by commenting on
-the GitHub issue that you want to work on it. This is to prevent duplicated
-efforts from contributors on the same issue.
-
-Head over to [Servo Starters](https://starters.servo.org/) to find
-good tasks to start with. If you come across words or jargon that do not make
-sense, please check [the glossary](docs/glossary.md) first. If there's no
-matching entry, please make a pull request to add one with the content `TODO`
-so we can correct that!
-
-See [`HACKING_QUICKSTART.md`](docs/HACKING_QUICKSTART.md) for more information
-on how to start working on Servo.
-
-## Pull request checklist
-
-- Branch from the main branch and, if needed, rebase to the current main branch
-  before submitting your pull request. If it doesn't merge cleanly with main
-  you may be asked to rebase your changes.
-
-- Commits should be as small as possible, while ensuring that each commit is
-  correct independently (i.e., each commit should compile and pass tests). 
-
-- Commits should be accompanied by a Developer Certificate of Origin
-  (http://developercertificate.org) sign-off, which indicates that you (and
-  your employer if applicable) agree to be bound by the terms of the
-  [project license](LICENSE). In git, this is the `-s` option to `git commit`.
-
-- If your patch is not getting reviewed or you need a specific person to review
-  it, you can @-reply a reviewer asking for a review in the pull request or a
-  comment, or you can ask for a review in [the Servo chat](https://servo.zulipchat.com/).
-
-- Add tests relevant to the fixed bug or new feature.  For a DOM change this
-  will usually be a web platform test; for layout, a reftest.  See our [testing
-  guide](https://github.com/servo/servo/wiki/Testing) for more information.
-
-For specific git instructions, see [GitHub workflow 101](https://github.com/servo/servo/wiki/Github-workflow).
-
-## Running tests in pull requests
-
-When you push to a pull request, GitHub automatically checks that your changes have no compilation, lint, or tidy errors.
-
-To run unit tests or Web Platform Tests against a pull request, add one or more of the labels below to your pull request. If you do not have permission to add labels to your pull request, add a comment on your bug requesting that they be added.
-
-| Label | Effect |
-|---|---|
-| `T-full` | Unit tests: Linux, macOS, Windows<br>Layout tests: Linux, macOS<br>Legacy layout tests: Linux, macOS |
-| `T-linux-wpt-2013` | Unit tests: Linux<br>Legacy layout tests: Linux |
-| `T-linux-wpt-2020` | Unit tests: Linux<br>Layout tests: Linux |
-| `T-macos` | Unit tests: macOS |
-| `T-windows` | Unit tests: Windows |
-
-## Conduct
-
-Servo Code of Conduct is published at <https://servo.org/coc/>.
-
-## Communication
-
-Servo contributors frequent the [Servo Zulip chat](https://servo.zulipchat.com/).
-
-## Technical Steering Committee
-
-Technical oversight of the Servo Project is provided by the
-[Technical Steering Committee](https://github.com/servo/project/blob/main/governance/tsc/README.md).
+Moved to the Servo book:
 
+- [Contributing to Servo](https://book.servo.org/contributing.html)

Cargo.toml

@@ -25,18 +25,20 @@ background_hang_monitor_api = { path = "components/shared/background_hang_monito
 backtrace = "0.3"
 base = { path = "components/shared/base" }
 base64 = "0.21.7"
-bitflags = "2.5"
+bincode = "1"
+bitflags = "2.6"
 bluetooth_traits = { path = "components/shared/bluetooth" }
 byteorder = "1.5"
 canvas_traits = { path = "components/shared/canvas" }
 cfg-if = "1.0.0"
+chrono = { version = "0.4", features = ["serde"] }
 compositing_traits = { path = "components/shared/compositing" }
 content-security-policy = { version = "0.5", features = ["serde"] }
-cookie = "0.12"
+cookie = { package = "cookie", version = "0.18" }
 crossbeam-channel = "0.5"
 cssparser = { version = "0.34", features = ["serde"] }
 darling = { version = "0.20", default-features = false }
-data-url = "0.1.0"
+data-url = "0.3"
 devtools_traits = { path = "components/shared/devtools" }
 embedder_traits = { path = "components/shared/embedder" }
 encoding_rs = "0.8"
@@ -56,7 +58,7 @@ gstreamer-gl-sys = "0.22"
 gstreamer-sys = "0.22"
 gstreamer-video = "0.22"
 headers = "0.3"
-html5ever = "0.27"
+html5ever = "0.28"
 http = "0.2"
 hyper = "0.14"
 hyper-rustls = { version = "0.24", default-features = false, features = ["acceptor", "http1", "http2", "logging", "tls12", "webpki-tokio"] }
@@ -64,21 +66,22 @@ hyper_serde = { path = "components/hyper_serde" }
 icu_segmenter = "1.5.0"
 image = "0.24"
 imsz = "0.2"
-indexmap = { version = "2.2.6", features = ["std"] }
+indexmap = { version = "2.5.0", features = ["std"] }
 ipc-channel = "0.18"
 itertools = "0.13"
-jemalloc-sys = "0.5.4"
-jemallocator = "0.5.4"
+tikv-jemalloc-sys = "0.6.0"
+tikv-jemallocator = "0.6.0"
 keyboard-types = "0.7"
-lazy_static = "1.4"
 libc = "0.2"
 log = "0.4"
-malloc_size_of = { git = "https://github.com/servo/stylo", branch = "2024-05-15", features = ["servo"] }
+mach2 = "0.4"
+malloc_size_of = { git = "https://github.com/servo/stylo", branch = "2024-07-16", features = ["servo"] }
 malloc_size_of_derive = "0.1"
 mime = "0.3.13"
-mime_guess = "2.0.3"
+mime_guess = "2.0.5"
 mozangle = "0.5.1"
 net_traits = { path = "components/shared/net" }
+nix = "0.29"
 num-traits = "0.2"
 num_cpus = "1.1.0"
 parking_lot = "0.12"
@@ -95,51 +98,55 @@ rustls = { version = "0.21.12", features = ["dangerous_configuration"] }
 rustls-pemfile = "1.0.4"
 script_layout_interface = { path = "components/shared/script_layout" }
 script_traits = { path = "components/shared/script" }
-selectors = { git = "https://github.com/servo/stylo", branch = "2024-05-15" }
-serde = "1.0.203"
+selectors = { git = "https://github.com/servo/stylo", branch = "2024-07-16" }
+serde = "1.0.209"
 serde_bytes = "0.11"
 serde_json = "1.0"
 servo-media = { git = "https://github.com/servo/media" }
 servo-media-dummy = { git = "https://github.com/servo/media" }
 servo-media-gstreamer = { git = "https://github.com/servo/media" }
-servo_arc = { git = "https://github.com/servo/stylo", branch = "2024-05-15" }
-servo_atoms = { git = "https://github.com/servo/stylo", branch = "2024-05-15" }
-size_of_test = { git = "https://github.com/servo/stylo", branch = "2024-05-15" }
+servo_arc = { git = "https://github.com/servo/stylo", branch = "2024-07-16", features = ["servo"] }
+servo_atoms = { git = "https://github.com/servo/stylo", branch = "2024-07-16" }
+size_of_test = { git = "https://github.com/servo/stylo", branch = "2024-07-16" }
 smallbitvec = "2.5.3"
 smallvec = "1.13"
 sparkle = "0.1.26"
 string_cache = "0.8"
 string_cache_codegen = "0.5"
-style = { git = "https://github.com/servo/stylo", branch = "2024-05-15", features = ["servo"] }
-style_config = { git = "https://github.com/servo/stylo", branch = "2024-05-15" }
-style_traits = { git = "https://github.com/servo/stylo", branch = "2024-05-15", features = ["servo"] }
-# NOTE: the sm-angle feature only enables ANGLE on Windows, not other platforms!
-surfman = { version = "0.9", features = ["chains", "sm-angle", "sm-angle-default"] }
+style = { git = "https://github.com/servo/stylo", branch = "2024-07-16", features = ["servo"] }
+style_config = { git = "https://github.com/servo/stylo", branch = "2024-07-16" }
+style_dom = { git = "https://github.com/servo/stylo", package = "dom", branch = "2024-07-16" }
+style_traits = { git = "https://github.com/servo/stylo", branch = "2024-07-16", features = ["servo"] }
+surfman = { version = "0.9.8", features = ["chains"] }
 syn = { version = "2", default-features = false, features = ["clone-impls", "derive", "parsing"] }
 synstructure = "0.13"
 thin-vec = "0.2.13"
 time = "0.1.41"
-to_shmem = { git = "https://github.com/servo/stylo", branch = "2024-05-15" }
+time_03 = { package = "time", version = "0.3", features = ["large-dates", "serde"] }
+to_shmem = { git = "https://github.com/servo/stylo", branch = "2024-07-16" }
 tokio = "1"
 tokio-rustls = "0.24"
 tungstenite = "0.20"
+tracing = "0.1.40"
+tracing-subscriber = "0.3.18"
+tracing-perfetto = "0.1.1"
 uluru = "3.0"
 unicode-bidi = "0.3.15"
-unicode-properties = { version = "0.1.1", features = ["emoji"] }
+unicode-properties = { version = "0.1.2", features = ["emoji"] }
 unicode-script = "0.5"
 unicode-segmentation = "1.1.0"
 url = "2.5"
-uuid = { version = "1.8.0", features = ["v4"] }
+uuid = { version = "1.10.0", features = ["v4"] }
 webdriver = "0.49.0"
 webpki-roots = "0.25"
-webrender = { git = "https://github.com/servo/webrender", branch = "0.64", features = ["capture"] }
-webrender_api = { git = "https://github.com/servo/webrender", branch = "0.64" }
+webrender = { git = "https://github.com/servo/webrender", branch = "0.65", features = ["capture"] }
+webrender_api = { git = "https://github.com/servo/webrender", branch = "0.65" }
 webrender_traits = { path = "components/shared/webrender" }
-wgpu-core = { git = "https://github.com/gfx-rs/wgpu", rev = "d0a5e48aa7e84683114c3870051cc414ae92ac03" }
-wgpu-types = { git = "https://github.com/gfx-rs/wgpu", rev = "d0a5e48aa7e84683114c3870051cc414ae92ac03" }
-windows-sys = "0.52"
-xi-unicode = "0.1.0"
-xml5ever = "0.18"
+wgpu-core = { git = "https://github.com/gfx-rs/wgpu", rev = "0e352f5b3448236b6cbebcd146d0606b00cb3806" }
+wgpu-types = { git = "https://github.com/gfx-rs/wgpu", rev = "0e352f5b3448236b6cbebcd146d0606b00cb3806" }
+windows-sys = "0.59"
+xi-unicode = "0.3.0"
+xml5ever = "0.19"
 
 [profile.release]
 opt-level = 3
@@ -151,6 +158,12 @@ debug-assertions = true
 [profile.production]
 inherits = "release"
 debug-assertions = false
+lto = "thin"
+codegen-units = 1
+
+[profile.production-stripped]
+inherits = "production"
+strip = true
 
 [patch.crates-io]
 # If you need to temporarily test Servo with a local fork of some upstream
@@ -162,6 +175,7 @@ debug-assertions = false
 #
 # [patch."https://github.com/servo/stylo"]
 # derive_common = { path = "../stylo/derive_common" }
+# dom = { path = "../stylo/dom" }
 # malloc_size_of = { path = "../stylo/malloc_size_of" }
 # selectors = { path = "../stylo/selectors" }
 # servo_arc = { path = "../stylo/servo_arc" }
@@ -174,6 +188,12 @@ debug-assertions = false
 # style_traits = { path = "../stylo/style_traits" }
 # to_shmem = { path = "../stylo/to_shmem" }
 #
+# Or for WebRender:
+#
+# [patch."https://github.com/servo/webrender"]
+# webrender = { path = "../webrender/webrender" }
+# webrender_api = { path = "../webrender/webrender_api" }
+#
 # Or for another Git dependency:
 #
 # [patch."https://github.com/servo/<repository>"]

README.md

@@ -4,79 +4,50 @@ Servo is a prototype web browser engine written in the
 [Rust](https://github.com/rust-lang/rust) language. It is currently developed on
 64-bit macOS, 64-bit Linux, 64-bit Windows, and Android.
 
-Servo welcomes contribution from everyone.  See
-[`CONTRIBUTING.md`](CONTRIBUTING.md) and [`HACKING_QUICKSTART.md`](docs/HACKING_QUICKSTART.md)
-for help getting started.
+Servo welcomes contribution from everyone. Check out [The Servo Book](https://book.servo.org) to get started, or go to [servo.org](https://servo.org/) for news and guides.
 
-Visit the [Servo Project page](https://servo.org/) for news and guides.
+## Getting started
 
-## Getting Servo
-
-``` sh
-git clone https://github.com/servo/servo
-cd servo
-```
-
- - Your CARGO_HOME needs to point to (or be in) the same drive as your 
-   Servo repository ([#28530](https://github.com/servo/servo/issues/28530)).
- - The Servo repository is big! If you have an unreliable network connection, consider
-   [making a shallow clone](https://github.blog/2020-12-21-get-up-to-speed-with-partial-clone-and-shallow-clone/).
-
-
-## Build Setup
-
-* [macOS](#macos)
-* [Linux](#Linux)
-* [Windows](#windows)
-* [Android](https://github.com/servo/servo/wiki/Building-for-Android)
-
-If these instructions fail or you would like to install dependencies
-manually, try the [manual build setup][manual-build].
+For more detailed build instructions, see the Servo book under [Setting up your environment](https://book.servo.org/hacking/setting-up-your-environment.html), [Building Servo](https://book.servo.org/hacking/building-servo.html), and [Building for Android](https://book.servo.org/hacking/building-for-android.html).
 
 ### macOS
 
-- Ensure that the version showed by `python --version` is >= 3.10:
-- Install [Xcode](https://developer.apple.com/xcode/)
-- Install [Homebrew](https://brew.sh/)
-- Run `curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh`
-- Run `./mach bootstrap`<br/>
-  *Note: This will install the recommended version of GStreamer globally on your system.*
+- Download and install [`python`](https://www.python.org/downloads/macos/), [Xcode](https://developer.apple.com/xcode/), and [`brew`](https://brew.sh/)
+- Install `rustup`: `curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh`
+- Restart your shell to make sure `cargo` is available
+- Install the other dependencies: `./mach bootstrap`
+- Build servoshell: `./mach build`
 
 ### Linux
 
-- Run `curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh`
-- Install Python (version >= 3.10):
-    - **Debian-like:** Run `sudo apt install python3-pip python3-venv`
-    - **Fedora:** Run `sudo dnf install python3 python3-pip python3-devel`
-    - **Arch:** Run `sudo pacman -S --needed python python-pip`
-    - **Gentoo:** Run `sudo emerge dev-python/pip`
-- Run `./mach bootstrap`
+- Install `curl` and `python`:
+  - Arch: `sudo pacman -S --needed curl python python-pip`
+  - Debian, Ubuntu: `sudo apt install curl python3-pip python3-venv`
+  - Fedora: `sudo dnf install curl python3 python3-pip python3-devel`
+  - Gentoo: `sudo emerge net-misc/curl dev-python/pip`
+- Install `rustup`: `curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh`
+- Restart your shell to make sure `cargo` is available
+- Install the other dependencies: `./mach bootstrap`
+- Build servoshell: `./mach build`
 
 ### Windows
 
- - Download and run [`rustup-init.exe`](https://win.rustup.rs/)
-  - Make sure to select *Quick install via the Visual Studio Community
-    installer* or otherwise install Visual Studio 2022.
- - In the *Visual Studio Installer* ensure the following components are installed for Visual Studio 2022:
-    - **Windows 10 SDK (10.0.19041.0)** (`Microsoft.VisualStudio.Component.Windows10SDK.19041`)
-    - **MSVC v143 - VS 2022 C++ x64/x86 build tools (Latest)** (`Microsoft.VisualStudio.Component.VC.Tools.x86.x64`)
-    - **C++ ATL for latest v143 build tools (x86 & x64)** (`Microsoft.VisualStudio.Component.VC.ATL`)
-    - **C++ MFC for latest v143 build tools (x86 & x64)** (`Microsoft.VisualStudio.Component.VC.ATLMFC`)
- - Install [chocolatey](https://chocolatey.org/)
- - Install [Python 3.11](https://www.python.org/downloads/windows/)
- - Run `mach bootstrap`
-    + *This will install CMake, Git, and Ninja via choco in an
-       Administrator console. Allow the scripts to run and once
-       the operation finishes, close the new console.*
-- Run `refreshenv`
-
-See also [Windows Troubleshooting Tips][windows-tips].
+- Download and install [`python`](https://www.python.org/downloads/windows/), [`choco`](https://chocolatey.org/install#individual), and [`rustup`](https://win.rustup.rs/)
+  - Be sure to select *Quick install via the Visual Studio Community installer*
+- In the Visual Studio Installer, ensure the following components are installed:
+  - **Windows 10 SDK (10.0.19041.0)** (`Microsoft.VisualStudio.Component.Windows10SDK.19041`)
+  - **MSVC v143 - VS 2022 C++ x64/x86 build tools (Latest)** (`Microsoft.VisualStudio.Component.VC.Tools.x86.x64`)
+  - **C++ ATL for latest v143 build tools (x86 & x64)** (`Microsoft.VisualStudio.Component.VC.ATL`)
+  - **C++ MFC for latest v143 build tools (x86 & x64)** (`Microsoft.VisualStudio.Component.VC.ATLMFC`)
+- Restart your shell to make sure `cargo` is available
+- Install the other dependencies: `.\mach bootstrap`
+- Build servoshell: `.\mach build`
 
 ### Android
 
 - Ensure that the following environment variables are set:
   - `ANDROID_SDK_ROOT`
-  - `ANDROID_NDK_ROOT`: `$ANDROID_SDK_ROOT/ndk/25.2.9519653/`
+  - `ANDROID_NDK_ROOT`: `$ANDROID_SDK_ROOT/ndk/26.2.11394342/`
  `ANDROID_SDK_ROOT` can be any directory (such as `~/android-sdk`).
   All of the Android build dependencies will be installed there.
 - Install the latest version of the [Android command-line
@@ -87,130 +58,9 @@ See also [Windows Troubleshooting Tips][windows-tips].
   sudo $ANDROID_SDK_ROOT/cmdline-tools/latest/bin/sdkmanager --install
    "build-tools;33.0.2" \
    "emulator" \
-   "ndk;25.2.9519653" \
+   "ndk;26.2.11394342" \
    "platform-tools" \
    "platforms;android-33" \
    "system-images;android-33;google_apis;x86_64"
   ```
-For information about building and running the Android build, see
-the [Android documentation][android-docs].
-
-## Building
-
-Servo is built with [Cargo](https://crates.io/), the Rust package manager.
-We also use Mozilla's Mach tools to orchestrate the build and other tasks.
-You can call Mach like this:
-
-On Unix systems:
-```
-./mach [command] [arguments]
-```
-On Windows Commandline:
-```
-mach.bat [command] [arguments]
-```
-The examples below will use Unix, but the same applies to Windows.
-
-### The Rust compiler
-
-Servo's build system uses rustup.rs to automatically download a Rust compiler.
-This is a specific version of Rust Nightly determined by the
-[`rust-toolchain.toml`](https://github.com/servo/servo/blob/main/rust-toolchain.toml) file.
-
-### Normal build
-
-To build Servo in development mode.
-This is useful for development, but the resulting binary is very slow:
-
-``` sh
-./mach build --dev
-./mach run tests/html/about-mozilla.html
-```
-
-### Release build
-For benchmarking, performance testing, or real-world use.
-Add the `--release` flag to create an optimized build:
-
-``` sh
-./mach build --release
-./mach run --release tests/html/about-mozilla.html
-```
-
-### Android build
-
-For an armv7 Android build run the following command.
-
-```shell
-./mach build --android
-```
-
-### Checking for build errors, without building
-
-If you’re making changes to one crate that cause build errors in another crate,
-consider this instead of a full build:
-
-```sh
-./mach check
-```
-
-It will run `cargo check`, which runs the analysis phase of the compiler
-(and so shows build errors if any) but skips the code generation phase.
-This can be a lot faster than a full build,
-though of course it doesn’t produce a binary you can run.
-
-## Running
-
-Run Servo with the command:
-
-```sh
-./servo [url] [arguments] # if you run with nightly build
-./mach run [url] [arguments] # if you run with mach
-
-# For example
-./mach run https://www.google.com
-```
-
-### Commandline Arguments
-
-- `-p INTERVAL` turns on the profiler and dumps info to the console every
-  `INTERVAL` seconds
-- `-s SIZE` sets the tile size for painting; defaults to 512
-- `-z` disables all graphical output; useful for running JS / layout tests
-- `-Z help` displays useful output to debug servo
-
-### Keyboard Shortcuts
-
-- `Ctrl`+`L` opens URL prompt (`Cmd`+`L` on Mac)
-- `Ctrl`+`R` reloads current page (`Cmd`+`R` on Mac)
-- `Ctrl`+`-` zooms out (`Cmd`+`-` on Mac)
-- `Ctrl`+`=` zooms in (`Cmd`+`=` on Mac)
-- `Alt`+`left arrow` goes backwards in the history (`Cmd`+`left arrow` on Mac)
-- `Alt`+`right arrow` goes forwards in the history (`Cmd`+`right arrow` on Mac)
-- `Esc` or `Ctrl`+`Q` exits Servo (`Cmd`+`Q` on Mac)
-
-### Runtime dependencies
-
-#### Linux
-
-* `GStreamer` >=1.18
-* `gst-plugins-base` >=1.18
-* `gst-plugins-good` >=1.18
-* `gst-plugins-bad` >=1.18
-* `gst-plugins-ugly` >=1.18
-* `libXcursor`
-* `libXrandr`
-* `libXi`
-* `libxkbcommon`
-* `vulkan-loader`
-
-## Developing
-
-There are lots of mach commands you can use. You can list them with `./mach
---help`.
-
-
-The generated documentation can be found on https://doc.servo.org/servo/index.html
-
-[manual-build]: https://github.com/servo/servo/wiki/Building#manual-build-setup
-[windows-tips]: https://github.com/servo/servo/wiki/Building#troubleshooting-the-windows-build
-[android-docs]: https://github.com/servo/servo/wiki/Building-for-Android
+- Follow the instructions above for the platform you are building on

components/allocator/Cargo.toml

@@ -13,8 +13,8 @@ path = "lib.rs"
 use-system-allocator = ["libc"]
 
 [target.'cfg(not(any(windows, target_env = "ohos")))'.dependencies]
-jemallocator = { workspace = true }
-jemalloc-sys = { workspace = true }
+tikv-jemallocator = { workspace = true }
+tikv-jemalloc-sys = { workspace = true }
 libc = { workspace = true, optional = true }
 
 [target.'cfg(windows)'.dependencies]

components/allocator/lib.rs

@@ -13,7 +13,7 @@ pub use crate::platform::*;
 mod platform {
     use std::os::raw::c_void;
 
-    pub use jemallocator::Jemalloc as Allocator;
+    pub use tikv_jemallocator::Jemalloc as Allocator;
 
     /// Get the size of a heap block.
     ///
@@ -21,12 +21,12 @@ mod platform {
     ///
     /// Passing a non-heap allocated pointer to this function results in undefined behavior.
     pub unsafe extern "C" fn usable_size(ptr: *const c_void) -> usize {
-        jemallocator::usable_size(ptr)
+        tikv_jemallocator::usable_size(ptr)
     }
 
     /// Memory allocation APIs compatible with libc
     pub mod libc_compat {
-        pub use jemalloc_sys::{free, malloc, realloc};
+        pub use tikv_jemalloc_sys::{free, malloc, realloc};
     }
 }
 

components/background_hang_monitor/Cargo.toml

@@ -22,12 +22,9 @@ libc = { workspace = true }
 log = { workspace = true }
 serde_json = { workspace = true }
 
-[dev-dependencies]
-lazy_static = { workspace = true }
-
 [target.'cfg(target_os = "macos")'.dependencies]
 mach2 = "0.4"
 
-[target.'cfg(all(target_os = "linux", not(any(target_arch = "arm", target_arch = "aarch64"))))'.dependencies]
-nix = { version = "0.27", features = ["signal"] }
+[target.'cfg(all(target_os = "linux", not(any(target_arch = "arm", target_arch = "aarch64", target_env = "ohos", target_env = "musl"))))'.dependencies]
+nix = { workspace = true, features = ["signal"] }
 unwind-sys = "0.1.4"

components/background_hang_monitor/background_hang_monitor.rs

@@ -98,12 +98,25 @@ impl BackgroundHangMonitorRegister for HangMonitorRegister {
         let sampler = crate::sampler_mac::MacOsSampler::new_boxed();
         #[cfg(all(
             target_os = "linux",
-            not(any(target_arch = "arm", target_arch = "aarch64"))
+            not(any(
+                target_arch = "arm",
+                target_arch = "aarch64",
+                target_env = "ohos",
+                target_env = "musl"
+            )),
         ))]
         let sampler = crate::sampler_linux::LinuxSampler::new_boxed();
         #[cfg(any(
             target_os = "android",
-            all(target_os = "linux", any(target_arch = "arm", target_arch = "aarch64"))
+            all(
+                target_os = "linux",
+                any(
+                    target_arch = "arm",
+                    target_arch = "aarch64",
+                    target_env = "ohos",
+                    target_env = "musl"
+                )
+            )
         ))]
         let sampler = crate::sampler::DummySampler::new_boxed();
 

components/background_hang_monitor/lib.rs

@@ -8,7 +8,12 @@ pub mod background_hang_monitor;
 mod sampler;
 #[cfg(all(
     target_os = "linux",
-    not(any(target_arch = "arm", target_arch = "aarch64"))
+    not(any(
+        target_arch = "arm",
+        target_arch = "aarch64",
+        target_env = "ohos",
+        target_env = "musl"
+    ))
 ))]
 mod sampler_linux;
 #[cfg(target_os = "macos")]

components/background_hang_monitor/tests/hang_monitor_tests.rs

@@ -17,9 +17,7 @@ use background_hang_monitor_api::{
 use base::id::TEST_PIPELINE_ID;
 use ipc_channel::ipc;
 
-lazy_static::lazy_static! {
-    static ref SERIAL: Mutex<()> = Mutex::new(());
-}
+static SERIAL: Mutex<()> = Mutex::new(());
 
 #[test]
 fn test_hang_monitoring() {

components/bluetooth/empty.rs

@@ -6,7 +6,7 @@ use std::collections::HashMap;
 use std::error::Error;
 use std::sync::Arc;
 
-const NOT_SUPPORTED_ERROR: &'static str = "Error! Not supported platform!";
+const NOT_SUPPORTED_ERROR: &str = "Error! Not supported platform!";
 
 #[derive(Clone, Debug)]
 pub struct EmptyAdapter {}

components/canvas/Cargo.toml

@@ -11,18 +11,17 @@ name = "canvas"
 path = "lib.rs"
 
 [features]
-no-wgl = ["surfman/sm-no-wgl"]
 webgl_backtrace = ["canvas_traits/webgl_backtrace"]
-xr-profile = ["webxr-api/profile", "time"]
 
 [dependencies]
+app_units = { workspace = true }
 bitflags = { workspace = true }
 byteorder = { workspace = true }
 canvas_traits = { workspace = true }
 crossbeam-channel = { workspace = true }
 cssparser = { workspace = true }
 euclid = { workspace = true }
-font-kit = { version = "0.13" }
+font-kit = { version = "0.14" }
 fnv = { workspace = true }
 fonts = { path = "../fonts" }
 half = "2"
@@ -31,15 +30,17 @@ log = { workspace = true }
 lyon_geom = "1.0.4"
 net_traits = { workspace = true }
 num-traits = { workspace = true }
+parking_lot = { workspace = true }
 pathfinder_geometry = "0.5"
 pixels = { path = "../pixels" }
-raqote = "0.8.4"
+range = { path = "../range" }
+raqote = { git = "https://github.com/jrmuizel/raqote", rev = "64716c8" }
 servo_arc = { workspace = true }
 sparkle = { workspace = true }
 style = { workspace = true }
 style_traits = { workspace = true }
 surfman = { workspace = true }
-time = { workspace = true, optional = true }
+unicode-script = { workspace = true }
 webrender = { workspace = true }
 webrender_api = { workspace = true }
 webrender_traits = { workspace = true }

components/canvas/canvas_data.rs

@@ -5,23 +5,22 @@
 use std::mem;
 use std::sync::Arc;
 
+use app_units::Au;
 use canvas_traits::canvas::*;
-use euclid::default::{Point2D, Rect, Size2D, Transform2D, Vector2D};
-use euclid::{point2, vec2};
-use font_kit::family_name::FamilyName;
-use font_kit::font::Font;
-use font_kit::metrics::Metrics;
-use font_kit::properties::{Properties, Stretch, Style, Weight};
-use font_kit::source::SystemSource;
-use fonts::{FontCacheThread, FontContext, FontTemplateRefMethods};
+use euclid::default::{Box2D, Point2D, Rect, Size2D, Transform2D, Vector2D};
+use euclid::point2;
+use fonts::{
+    ByteIndex, FontBaseline, FontCacheThread, FontContext, FontGroup, FontMetrics, FontRef,
+    GlyphInfo, GlyphStore, ShapingFlags, ShapingOptions, LAST_RESORT_GLYPH_ADVANCE,
+};
 use ipc_channel::ipc::{IpcSender, IpcSharedMemory};
-use log::{debug, error, warn};
+use log::{debug, warn};
 use num_traits::ToPrimitive;
+use range::Range;
 use servo_arc::Arc as ServoArc;
 use style::color::AbsoluteColor;
 use style::properties::style_structs::Font as FontStyleStruct;
-use style::values::computed::font;
-use style_traits::values::ToCss;
+use unicode_script::Script;
 use webrender_api::units::{DeviceIntSize, RectExt as RectExt_};
 use webrender_api::{ImageData, ImageDescriptor, ImageDescriptorFlags, ImageFormat, ImageKey};
 use webrender_traits::ImageUpdate;
@@ -232,10 +231,78 @@ impl<'a> PathBuilderRef<'a> {
     }
 }
 
-// TODO(pylbrecht)
-// This defines required methods for DrawTarget of azure and raqote
-// The prototypes are derived from azure's methods.
-// TODO: De-abstract now that Azure is removed?
+#[derive(Debug, Default)]
+struct UnshapedTextRun<'a> {
+    font: Option<FontRef>,
+    script: Script,
+    string: &'a str,
+}
+
+impl<'a> UnshapedTextRun<'a> {
+    fn script_and_font_compatible(&self, script: Script, other_font: &Option<FontRef>) -> bool {
+        if self.script != script {
+            return false;
+        }
+
+        match (&self.font, other_font) {
+            (Some(font_a), Some(font_b)) => font_a.identifier() == font_b.identifier(),
+            (None, None) => true,
+            _ => false,
+        }
+    }
+
+    fn into_shaped_text_run(self) -> Option<TextRun> {
+        let font = self.font?;
+        if self.string.is_empty() {
+            return None;
+        }
+
+        let word_spacing = Au::from_f64_px(
+            font.glyph_index(' ')
+                .map(|glyph_id| font.glyph_h_advance(glyph_id))
+                .unwrap_or(LAST_RESORT_GLYPH_ADVANCE),
+        );
+        let options = ShapingOptions {
+            letter_spacing: None,
+            word_spacing,
+            script: self.script,
+            flags: ShapingFlags::empty(),
+        };
+        let glyphs = font.shape_text(self.string, &options);
+        Some(TextRun { font, glyphs })
+    }
+}
+
+pub struct TextRun {
+    pub font: FontRef,
+    pub glyphs: Arc<GlyphStore>,
+}
+
+impl TextRun {
+    fn bounding_box(&self) -> Rect<f32> {
+        let mut bounding_box = None;
+        let mut bounds_offset: f32 = 0.;
+        let glyph_ids = self
+            .glyphs
+            .iter_glyphs_for_byte_range(&Range::new(ByteIndex(0), self.glyphs.len()))
+            .map(GlyphInfo::id);
+        for glyph_id in glyph_ids {
+            let bounds = self.font.typographic_bounds(glyph_id);
+            let amount = Vector2D::new(bounds_offset, 0.);
+            let bounds = bounds.translate(amount);
+            let initiated_bbox = bounding_box.get_or_insert_with(|| {
+                let origin = Point2D::new(bounds.min_x(), 0.);
+                Box2D::new(origin, origin).to_rect()
+            });
+            bounding_box = Some(initiated_bbox.union(&bounds));
+            bounds_offset = bounds.max_x();
+        }
+        bounding_box.unwrap_or_default()
+    }
+}
+
+// This defines required methods for a DrawTarget (currently only implemented for raqote).  The
+// prototypes are derived from the now-removed Azure backend's methods.
 pub trait GenericDrawTarget {
     fn clear_rect(&mut self, rect: &Rect<f32>);
     fn copy_surface(
@@ -268,9 +335,7 @@ pub trait GenericDrawTarget {
     fn fill(&mut self, path: &Path, pattern: Pattern, draw_options: &DrawOptions);
     fn fill_text(
         &mut self,
-        font: &Font,
-        point_size: f32,
-        text: &str,
+        text_runs: Vec<TextRun>,
         start: Point2D<f32>,
         pattern: &Pattern,
         draw_options: &DrawOptions,
@@ -455,7 +520,85 @@ impl<'a> CanvasData<'a> {
         }
     }
 
-    // https://html.spec.whatwg.org/multipage/#text-preparation-algorithm
+    pub fn fill_text_with_size(
+        &mut self,
+        text: String,
+        x: f64,
+        y: f64,
+        max_width: Option<f64>,
+        is_rtl: bool,
+        size: f64,
+    ) {
+        // > Step 2: Replace all ASCII whitespace in text with U+0020 SPACE characters.
+        let text = replace_ascii_whitespace(text);
+
+        // > Step 3: Let font be the current font of target, as given by that object's font
+        // > attribute.
+        let Some(ref font_style) = self.state.font_style else {
+            return;
+        };
+
+        let font_group = self
+            .font_context
+            .font_group_with_size(font_style.clone(), Au::from_f64_px(size));
+        let mut font_group = font_group.write();
+        let Some(first_font) = font_group.first(&self.font_context) else {
+            warn!("Could not render canvas text, because there was no first font.");
+            return;
+        };
+
+        let runs = self.build_unshaped_text_runs(&text, &mut font_group);
+        // TODO: This doesn't do any kind of line layout at all. In particular, there needs
+        // to be some alignment along a baseline and also support for bidi text.
+        let shaped_runs: Vec<_> = runs
+            .into_iter()
+            .filter_map(UnshapedTextRun::into_shaped_text_run)
+            .collect();
+        let total_advance = shaped_runs
+            .iter()
+            .map(|run| run.glyphs.total_advance())
+            .sum::<Au>()
+            .to_f64_px();
+
+        // > Step 6: If maxWidth was provided and the hypothetical width of the inline box in the
+        // > hypothetical line box is greater than maxWidth CSS pixels, then change font to have a
+        // > more condensed font (if one is available or if a reasonably readable one can be
+        // > synthesized by applying a horizontal scale factor to the font) or a smaller font, and
+        // > return to the previous step.
+        //
+        // TODO: We only try decreasing the font size here. Eventually it would make sense to use
+        // other methods to try to decrease the size, such as finding a narrower font or decreasing
+        // spacing.
+        if let Some(max_width) = max_width {
+            let new_size = (max_width / total_advance * size).floor().max(5.);
+            if total_advance > max_width && new_size != size {
+                self.fill_text_with_size(text, x, y, Some(max_width), is_rtl, new_size);
+                return;
+            }
+        }
+
+        // > Step 7: Find the anchor point for the line of text.
+        let start = self.find_anchor_point_for_line_of_text(
+            x as f32,
+            y as f32,
+            &first_font.metrics,
+            total_advance as f32,
+            is_rtl,
+        );
+
+        // > Step 8: Let result be an array constructed by iterating over each glyph in the inline box
+        // > from left to right (if any), adding to the array, for each glyph, the shape of the glyph
+        // > as it is in the inline box, positioned on a coordinate space using CSS pixels with its
+        // > origin is at the anchor point.
+        self.drawtarget.fill_text(
+            shaped_runs,
+            start,
+            &self.state.fill_style,
+            &self.state.draw_options,
+        );
+    }
+
+    /// <https://html.spec.whatwg.org/multipage/#text-preparation-algorithm>
     pub fn fill_text(
         &mut self,
         text: String,
@@ -464,77 +607,138 @@ impl<'a> CanvasData<'a> {
         max_width: Option<f64>,
         is_rtl: bool,
     ) {
-        // Step 2.
-        let text = replace_ascii_whitespace(text);
-
-        // Step 3.
-        let point_size = self
-            .state
-            .font_style
-            .as_ref()
-            .map_or(10., |style| style.font_size.computed_size().px());
-        let font_style = self.state.font_style.as_ref();
-        let font = font_style.map_or_else(
-            || load_system_font_from_style(None),
-            |style| {
-                let font_group = self.font_context.font_group(ServoArc::new(style.clone()));
-                let font = font_group
-                    .write()
-                    .first(&self.font_context)
-                    .expect("couldn't find font");
-                Font::from_bytes(font.template.data(), 0)
-                    .ok()
-                    .or_else(|| load_system_font_from_style(Some(style)))
-            },
-        );
-        let font = match font {
-            Some(f) => f,
-            None => {
-                error!("Couldn't load desired font or system fallback.");
-                return;
-            },
-        };
-        let font_width = font_width(&text, point_size, &font);
-
-        // Step 6.
-        let max_width = max_width.map(|width| width as f32);
-        let (width, scale_factor) = match max_width {
-            Some(max_width) if max_width > font_width => (max_width, 1.),
-            Some(max_width) => (font_width, max_width / font_width),
-            None => (font_width, 1.),
+        let Some(ref font_style) = self.state.font_style else {
+            return;
         };
 
-        // Step 7.
-        let start = self.text_origin(x as f32, y as f32, &font.metrics(), width, is_rtl);
-
-        // TODO: Bidi text layout
-
-        let old_transform = self.get_transform();
-        self.set_transform(
-            &old_transform
-                .pre_translate(vec2(start.x, 0.))
-                .pre_scale(scale_factor, 1.)
-                .pre_translate(vec2(-start.x, 0.)),
-        );
-
-        // Step 8.
-        self.drawtarget.fill_text(
-            &font,
-            point_size,
-            &text,
-            start,
-            &self.state.fill_style,
-            &self.state.draw_options,
-        );
-
-        self.set_transform(&old_transform);
+        let size = font_style.font_size.computed_size();
+        self.fill_text_with_size(text, x, y, max_width, is_rtl, size.px() as f64);
     }
 
-    fn text_origin(
+    /// <https://html.spec.whatwg.org/multipage/#text-preparation-algorithm>
+    /// <https://html.spec.whatwg.org/multipage/#dom-context-2d-measuretext>
+    pub fn measure_text(&mut self, text: String) -> TextMetrics {
+        // > Step 2: Replace all ASCII whitespace in text with U+0020 SPACE characters.
+        let text = replace_ascii_whitespace(text);
+        let Some(ref font_style) = self.state.font_style else {
+            return TextMetrics::default();
+        };
+
+        let font_group = self.font_context.font_group(font_style.clone());
+        let mut font_group = font_group.write();
+        let font = font_group
+            .first(&self.font_context)
+            .expect("couldn't find font");
+        let ascent = font.metrics.ascent.to_f32_px();
+        let descent = font.metrics.descent.to_f32_px();
+        let runs = self.build_unshaped_text_runs(&text, &mut font_group);
+
+        let shaped_runs: Vec<_> = runs
+            .into_iter()
+            .filter_map(UnshapedTextRun::into_shaped_text_run)
+            .collect();
+        let total_advance = shaped_runs
+            .iter()
+            .map(|run| run.glyphs.total_advance())
+            .sum::<Au>()
+            .to_f32_px();
+        let bounding_box = shaped_runs
+            .iter()
+            .map(TextRun::bounding_box)
+            .reduce(|a, b| {
+                let amount = Vector2D::new(a.max_x(), 0.);
+                let bounding_box = b.translate(amount);
+                a.union(&bounding_box)
+            })
+            .unwrap_or_default();
+
+        let FontBaseline {
+            ideographic_baseline,
+            alphabetic_baseline,
+            hanging_baseline,
+        } = match font.get_baseline() {
+            Some(baseline) => baseline,
+            None => FontBaseline {
+                hanging_baseline: ascent * HANGING_BASELINE_DEFAULT,
+                ideographic_baseline: -descent * IDEOGRAPHIC_BASELINE_DEFAULT,
+                alphabetic_baseline: 0.,
+            },
+        };
+
+        let anchor_x = match self.state.text_align {
+            TextAlign::End => total_advance,
+            TextAlign::Center => total_advance / 2.,
+            TextAlign::Right => total_advance,
+            _ => 0.,
+        };
+        let anchor_y = match self.state.text_baseline {
+            TextBaseline::Top => ascent,
+            TextBaseline::Hanging => hanging_baseline,
+            TextBaseline::Ideographic => ideographic_baseline,
+            TextBaseline::Middle => (ascent - descent) / 2.,
+            TextBaseline::Alphabetic => alphabetic_baseline,
+            TextBaseline::Bottom => -descent,
+        };
+
+        TextMetrics {
+            width: total_advance,
+            actual_boundingbox_left: anchor_x - bounding_box.min_x(),
+            actual_boundingbox_right: bounding_box.max_x() - anchor_x,
+            actual_boundingbox_ascent: bounding_box.max_y() - anchor_y,
+            actual_boundingbox_descent: anchor_y - bounding_box.min_y(),
+            font_boundingbox_ascent: ascent - anchor_y,
+            font_boundingbox_descent: descent + anchor_y,
+            em_height_ascent: ascent - anchor_y,
+            em_height_descent: descent + anchor_y,
+            hanging_baseline: hanging_baseline - anchor_y,
+            alphabetic_baseline: alphabetic_baseline - anchor_y,
+            ideographic_baseline: ideographic_baseline - anchor_y,
+        }
+    }
+
+    fn build_unshaped_text_runs<'b>(
+        &self,
+        text: &'b str,
+        font_group: &mut FontGroup,
+    ) -> Vec<UnshapedTextRun<'b>> {
+        let mut runs = Vec::new();
+        let mut current_text_run = UnshapedTextRun::default();
+        let mut current_text_run_start_index = 0;
+
+        for (index, character) in text.char_indices() {
+            // TODO: This should ultimately handle emoji variation selectors, but raqote does not yet
+            // have support for color glyphs.
+            let script = Script::from(character);
+            let font = font_group.find_by_codepoint(&self.font_context, character, None);
+
+            if !current_text_run.script_and_font_compatible(script, &font) {
+                let previous_text_run = mem::replace(
+                    &mut current_text_run,
+                    UnshapedTextRun {
+                        font: font.clone(),
+                        script,
+                        ..Default::default()
+                    },
+                );
+                current_text_run_start_index = index;
+                runs.push(previous_text_run)
+            }
+
+            current_text_run.string =
+                &text[current_text_run_start_index..index + character.len_utf8()];
+        }
+
+        runs.push(current_text_run);
+        runs
+    }
+
+    /// Find the *anchor_point* for the given parameters of a line of text.
+    /// See <https://html.spec.whatwg.org/multipage/#text-preparation-algorithm>.
+    fn find_anchor_point_for_line_of_text(
         &self,
         x: f32,
         y: f32,
-        metrics: &Metrics,
+        metrics: &FontMetrics,
         width: f32,
         is_rtl: bool,
     ) -> Point2D<f32> {
@@ -551,13 +755,15 @@ impl<'a> CanvasData<'a> {
             _ => 0.,
         };
 
+        let ascent = metrics.ascent.to_f32_px();
+        let descent = metrics.descent.to_f32_px();
         let anchor_y = match self.state.text_baseline {
-            TextBaseline::Top => metrics.ascent,
-            TextBaseline::Hanging => metrics.ascent * HANGING_BASELINE_DEFAULT,
-            TextBaseline::Ideographic => -metrics.descent * IDEOGRAPHIC_BASELINE_DEFAULT,
-            TextBaseline::Middle => (metrics.ascent - metrics.descent) / 2.,
+            TextBaseline::Top => ascent,
+            TextBaseline::Hanging => ascent * HANGING_BASELINE_DEFAULT,
+            TextBaseline::Ideographic => -descent * IDEOGRAPHIC_BASELINE_DEFAULT,
+            TextBaseline::Middle => (ascent - descent) / 2.,
             TextBaseline::Alphabetic => 0.,
-            TextBaseline::Bottom => -metrics.descent,
+            TextBaseline::Bottom => -descent,
         };
 
         point2(x + anchor_x, y + anchor_y)
@@ -1140,7 +1346,7 @@ impl<'a> CanvasData<'a> {
     }
 
     pub fn set_font(&mut self, font_style: FontStyleStruct) {
-        self.state.font_style = Some(font_style)
+        self.state.font_style = Some(ServoArc::new(font_style))
     }
 
     pub fn set_text_align(&mut self, text_align: TextAlign) {
@@ -1239,7 +1445,7 @@ pub struct CanvasPaintState<'a> {
     pub shadow_offset_y: f64,
     pub shadow_blur: f64,
     pub shadow_color: Color,
-    pub font_style: Option<FontStyleStruct>,
+    pub font_style: Option<ServoArc<FontStyleStruct>>,
     pub text_align: TextAlign,
     pub text_baseline: TextBaseline,
 }
@@ -1330,71 +1536,6 @@ impl RectExt for Rect<u32> {
     }
 }
 
-fn to_font_kit_family(font_family: &font::SingleFontFamily) -> FamilyName {
-    match font_family {
-        font::SingleFontFamily::FamilyName(family_name) => {
-            FamilyName::Title(family_name.to_css_string())
-        },
-        font::SingleFontFamily::Generic(generic) => match generic {
-            font::GenericFontFamily::Serif => FamilyName::Serif,
-            font::GenericFontFamily::SansSerif => FamilyName::SansSerif,
-            font::GenericFontFamily::Monospace => FamilyName::Monospace,
-            font::GenericFontFamily::Fantasy => FamilyName::Fantasy,
-            font::GenericFontFamily::Cursive => FamilyName::Cursive,
-            // TODO: There is no FontFamily::SystemUi.
-            font::GenericFontFamily::SystemUi => unreachable!("system-ui should be disabled"),
-            font::GenericFontFamily::None => unreachable!("Shouldn't appear in computed values"),
-        },
-    }
-}
-
-fn load_system_font_from_style(font_style: Option<&FontStyleStruct>) -> Option<Font> {
-    let mut properties = Properties::new();
-    let style = match font_style {
-        Some(style) => style,
-        None => return load_default_system_fallback_font(&properties),
-    };
-    let family_names = style
-        .font_family
-        .families
-        .iter()
-        .map(to_font_kit_family)
-        .collect::<Vec<_>>();
-    let properties = properties
-        .style(match style.font_style {
-            font::FontStyle::NORMAL => Style::Normal,
-            font::FontStyle::ITALIC => Style::Italic,
-            _ => {
-                // TODO: support oblique angle.
-                Style::Oblique
-            },
-        })
-        .weight(Weight(style.font_weight.value()))
-        .stretch(Stretch(style.font_stretch.to_percentage().0));
-    let font_handle = match SystemSource::new().select_best_match(&family_names, properties) {
-        Ok(handle) => handle,
-        Err(e) => {
-            error!("error getting font handle for style {:?}: {}", style, e);
-            return load_default_system_fallback_font(properties);
-        },
-    };
-    match font_handle.load() {
-        Ok(f) => Some(f),
-        Err(e) => {
-            error!("error loading font for style {:?}: {}", style, e);
-            load_default_system_fallback_font(properties)
-        },
-    }
-}
-
-fn load_default_system_fallback_font(properties: &Properties) -> Option<Font> {
-    SystemSource::new()
-        .select_best_match(&[FamilyName::SansSerif], properties)
-        .ok()?
-        .load()
-        .ok()
-}
-
 fn replace_ascii_whitespace(text: String) -> String {
     text.chars()
         .map(|c| match c {
@@ -1403,18 +1544,3 @@ fn replace_ascii_whitespace(text: String) -> String {
         })
         .collect()
 }
-
-// TODO: This currently calculates the width using just advances and doesn't
-// determine the fallback font in case a character glyph isn't found.
-fn font_width(text: &str, point_size: f32, font: &Font) -> f32 {
-    let metrics = font.metrics();
-    let mut width = 0.;
-    for c in text.chars() {
-        if let Some(glyph_id) = font.glyph_for_char(c) {
-            if let Ok(advance) = font.advance(glyph_id) {
-                width += advance.x() * point_size / metrics.units_per_em as f32;
-            }
-        }
-    }
-    width
-}

components/canvas/canvas_paint_thread.rs

@@ -234,6 +234,10 @@ impl<'a> CanvasPaintThread<'a> {
             Canvas2dMsg::Ellipse(ref center, radius_x, radius_y, rotation, start, end, ccw) => self
                 .canvas(canvas_id)
                 .ellipse(center, radius_x, radius_y, rotation, start, end, ccw),
+            Canvas2dMsg::MeasureText(text, sender) => {
+                let metrics = self.canvas(canvas_id).measure_text(text);
+                sender.send(metrics).unwrap();
+            },
             Canvas2dMsg::RestoreContext => self.canvas(canvas_id).restore_context_state(),
             Canvas2dMsg::SaveContext => self.canvas(canvas_id).save_context_state(),
             Canvas2dMsg::SetLineWidth(width) => self.canvas(canvas_id).set_line_width(width),

components/canvas/raqote_backend.rs

@@ -2,23 +2,36 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
+use std::cell::RefCell;
+use std::collections::HashMap;
+
 use canvas_traits::canvas::*;
 use cssparser::color::clamp_unit_f32;
 use euclid::default::{Point2D, Rect, Size2D, Transform2D, Vector2D};
 use euclid::Angle;
 use font_kit::font::Font;
+use fonts::{ByteIndex, FontIdentifier, FontTemplateRefMethods};
 use log::warn;
 use lyon_geom::Arc;
+use range::Range;
 use raqote::PathOp;
 use style::color::AbsoluteColor;
 
-use crate::canvas_data;
 use crate::canvas_data::{
-    Backend, CanvasPaintState, Color, CompositionOp, DrawOptions, Filter, GenericDrawTarget,
-    GenericPathBuilder, GradientStop, GradientStops, Path, SourceSurface, StrokeOptions,
+    self, Backend, CanvasPaintState, Color, CompositionOp, DrawOptions, Filter, GenericDrawTarget,
+    GenericPathBuilder, GradientStop, GradientStops, Path, SourceSurface, StrokeOptions, TextRun,
 };
 use crate::canvas_paint_thread::AntialiasMode;
 
+thread_local! {
+    /// The shared font cache used by all canvases that render on a thread. It would be nicer
+    /// to have a global cache, but it looks like font-kit uses a per-thread FreeType, so
+    /// in order to ensure that fonts are particular to a thread we have to make our own
+    /// cache thread local as well.
+    static SHARED_FONT_CACHE: RefCell<HashMap<FontIdentifier, Font>> = RefCell::default();
+}
+
+#[derive(Default)]
 pub struct RaqoteBackend;
 
 impl Backend for RaqoteBackend {
@@ -508,43 +521,61 @@ impl GenericDrawTarget for raqote::DrawTarget {
 
     fn fill_text(
         &mut self,
-        font: &Font,
-        point_size: f32,
-        text: &str,
+        text_runs: Vec<TextRun>,
         start: Point2D<f32>,
         pattern: &canvas_data::Pattern,
-        options: &DrawOptions,
+        draw_options: &DrawOptions,
     ) {
-        let mut start = pathfinder_geometry::vector::vec2f(start.x, start.y);
-        let mut ids = Vec::new();
-        let mut positions = Vec::new();
-        for c in text.chars() {
-            let id = match font.glyph_for_char(c) {
-                Some(id) => id,
-                None => {
-                    warn!("Skipping non-existent glyph {}", c);
-                    continue;
-                },
-            };
-            ids.push(id);
-            positions.push(Point2D::new(start.x(), start.y()));
-            let advance = match font.advance(id) {
-                Ok(advance) => advance,
-                Err(e) => {
-                    warn!("Skipping glyph {} with missing advance: {:?}", c, e);
-                    continue;
-                },
-            };
-            start += advance * point_size / 24. / 96.;
+        let mut advance = 0.;
+        for run in text_runs.iter() {
+            let mut positions = Vec::new();
+            let glyphs = &run.glyphs;
+            let ids: Vec<_> = glyphs
+                .iter_glyphs_for_byte_range(&Range::new(ByteIndex(0), glyphs.len()))
+                .map(|glyph| {
+                    let glyph_offset = glyph.offset().unwrap_or(Point2D::zero());
+                    positions.push(Point2D::new(
+                        advance + start.x + glyph_offset.x.to_f32_px(),
+                        start.y + glyph_offset.y.to_f32_px(),
+                    ));
+                    advance += glyph.advance().to_f32_px();
+                    glyph.id()
+                })
+                .collect();
+
+            // TODO: raqote uses font-kit to rasterize glyphs, but font-kit fails an assertion when
+            // using color bitmap fonts in the FreeType backend. For now, simply do not render these
+            // type of fonts.
+            if run.font.has_color_bitmap_or_colr_table() {
+                continue;
+            }
+
+            let template = &run.font.template;
+
+            SHARED_FONT_CACHE.with(|font_cache| {
+                let identifier = template.identifier();
+                if !font_cache.borrow().contains_key(&identifier) {
+                    let Ok(font) = Font::from_bytes(template.data(), identifier.index()) else {
+                        return;
+                    };
+                    font_cache.borrow_mut().insert(identifier.clone(), font);
+                }
+
+                let font_cache = font_cache.borrow();
+                let Some(font) = font_cache.get(&identifier) else {
+                    return;
+                };
+
+                self.draw_glyphs(
+                    font,
+                    run.font.descriptor.pt_size.to_f32_px(),
+                    &ids,
+                    &positions,
+                    &pattern.source(),
+                    draw_options.as_raqote(),
+                );
+            })
         }
-        self.draw_glyphs(
-            font,
-            point_size,
-            &ids,
-            &positions,
-            &pattern.source(),
-            options.as_raqote(),
-        );
     }
 
     fn fill_rect(

components/canvas/webgl_thread.rs

@@ -51,11 +51,6 @@ use webxr_api::{
 
 use crate::webgl_limits::GLLimitsDetect;
 
-#[cfg(feature = "xr-profile")]
-fn to_ms(ns: u64) -> f64 {
-    ns as f64 / 1_000_000.
-}
-
 struct GLContextData {
     ctx: Context,
     gl: Rc<Gl>,
@@ -373,7 +368,10 @@ impl WebGLThread {
             WebGLMsg::SwapBuffers(swap_ids, sender, sent_time) => {
                 self.handle_swap_buffers(swap_ids, sender, sent_time);
             },
-            WebGLMsg::Exit => {
+            WebGLMsg::Exit(sender) => {
+                if let Err(e) = sender.send(()) {
+                    warn!("Failed to send response to WebGLMsg::Exit ({e})");
+                }
                 return true;
             },
         }
@@ -829,14 +827,6 @@ impl WebGLThread {
 
         #[allow(unused)]
         let mut end_swap = 0;
-        #[cfg(feature = "xr-profile")]
-        {
-            end_swap = time::precise_time_ns();
-            println!(
-                "WEBXR PROFILING [swap buffer]:\t{}ms",
-                to_ms(end_swap - start_swap)
-            );
-        }
         completed_sender.send(end_swap).unwrap();
     }
 
@@ -1054,7 +1044,7 @@ impl WebGLImpl {
                 gl.clear_color(r, g, b, a);
             },
             WebGLCommand::ClearDepth(depth) => {
-                let value = depth.max(0.).min(1.) as f64;
+                let value = depth.clamp(0., 1.) as f64;
                 state.depth_clear_value = value;
                 gl.clear_depth(value)
             },
@@ -1093,7 +1083,7 @@ impl WebGLImpl {
                 state.restore_depth_invariant(gl);
             },
             WebGLCommand::DepthRange(near, far) => {
-                gl.depth_range(near.max(0.).min(1.) as f64, far.max(0.).min(1.) as f64)
+                gl.depth_range(near.clamp(0., 1.) as f64, far.clamp(0., 1.) as f64)
             },
             WebGLCommand::Disable(cap) => match cap {
                 gl::SCISSOR_TEST => {
@@ -2886,8 +2876,8 @@ fn flip_pixels_y(
 
 // Clamp a size to the current GL context's max viewport
 fn clamp_viewport(gl: &Gl, size: Size2D<u32>) -> Size2D<u32> {
-    let mut max_viewport = [i32::max_value(), i32::max_value()];
-    let mut max_renderbuffer = [i32::max_value()];
+    let mut max_viewport = [i32::MAX, i32::MAX];
+    let mut max_renderbuffer = [i32::MAX];
     #[allow(unsafe_code)]
     unsafe {
         gl.get_integer_v(gl::MAX_VIEWPORT_DIMS, &mut max_viewport);

components/compositing/Cargo.toml

@@ -1,6 +1,5 @@
 [package]
 name = "compositing"
-build = "build.rs"
 version.workspace = true
 authors.workspace = true
 license.workspace = true
@@ -31,6 +30,7 @@ ipc-channel = { workspace = true }
 keyboard-types = { workspace = true }
 libc = { workspace = true }
 log = { workspace = true }
+net = { path = "../net" }
 net_traits = { workspace = true }
 pixels = { path = "../pixels" }
 profile_traits = { workspace = true }
@@ -41,10 +41,11 @@ servo_geometry = { path = "../geometry" }
 servo_url = { path = "../url" }
 style_traits = { workspace = true }
 time = { workspace = true }
+tracing = { workspace = true }
 webrender = { workspace = true }
 webrender_api = { workspace = true }
 webrender_traits = { workspace = true }
 webxr = { git = "https://github.com/servo/webxr" }
 
-[build-dependencies]
-toml = "0.5"
+[dev-dependencies]
+surfman = { workspace = true }

components/compositing/build.rs

@@ -1,52 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
-
-use std::env;
-use std::fs::File;
-use std::io::{Read, Write};
-use std::path::Path;
-
-fn main() {
-    let lockfile_path = Path::new(&env::var("CARGO_MANIFEST_DIR").unwrap())
-        .join("..")
-        .join("..")
-        .join("Cargo.lock");
-    let revision_file_path =
-        Path::new(&env::var_os("OUT_DIR").unwrap()).join("webrender_revision.rs");
-
-    let mut lockfile = String::new();
-    File::open(lockfile_path)
-        .expect("Cannot open lockfile")
-        .read_to_string(&mut lockfile)
-        .expect("Failed to read lockfile");
-
-    match toml::from_str::<toml::value::Table>(&lockfile) {
-        Ok(result) => {
-            let packages = result
-                .get("package")
-                .expect("Cargo lockfile should contain package list");
-
-            match *packages {
-                toml::Value::Array(ref arr) => {
-                    let source = arr
-                        .iter()
-                        .find(|pkg| {
-                            pkg.get("name").and_then(|name| name.as_str()).unwrap_or("") ==
-                                "webrender"
-                        })
-                        .and_then(|pkg| pkg.get("source").and_then(|source| source.as_str()))
-                        .unwrap_or("unknown");
-
-                    let parsed: Vec<&str> = source.split('#').collect();
-                    let revision = if parsed.len() > 1 { parsed[1] } else { source };
-
-                    let mut revision_module_file = File::create(revision_file_path).unwrap();
-                    write!(&mut revision_module_file, "\"{}\"", revision).unwrap();
-                },
-                _ => panic!("Cannot find package definitions in lockfile"),
-            }
-        },
-        Err(e) => panic!("{}", e),
-    }
-}

components/compositing/compositor.rs

@@ -11,6 +11,7 @@ use std::iter::once;
 use std::rc::Rc;
 use std::time::{Duration, Instant, SystemTime, UNIX_EPOCH};
 
+use base::cross_process_instant::CrossProcessInstant;
 use base::id::{PipelineId, TopLevelBrowsingContextId, WebViewId};
 use base::{Epoch, WebRenderEpochToU16};
 use compositing_traits::{
@@ -34,6 +35,7 @@ use script_traits::{
 };
 use servo_geometry::{DeviceIndependentPixel, FramebufferUintLength};
 use style_traits::{CSSPixel, DevicePixel, PinchZoomFactor};
+use tracing::{span, Level};
 use webrender::{CaptureBits, RenderApi, Transaction};
 use webrender_api::units::{
     DeviceIntPoint, DeviceIntSize, DevicePoint, DeviceRect, LayoutPoint, LayoutRect, LayoutSize,
@@ -215,6 +217,10 @@ pub struct IOCompositor<Window: WindowMethods + ?Sized> {
     /// The [`Instant`] of the last animation tick, used to avoid flooding the Constellation and
     /// ScriptThread with a deluge of animation ticks.
     last_animation_tick: Instant,
+
+    /// The string representing the version of Servo that is running. This is used to tag
+    /// WebRender capture output.
+    version_string: String,
 }
 
 #[derive(Clone, Copy)]
@@ -350,13 +356,14 @@ pub enum CompositeTarget {
 }
 
 impl<Window: WindowMethods + ?Sized> IOCompositor<Window> {
-    fn new(
+    pub fn new(
         window: Rc<Window>,
         state: InitialCompositorState,
         composite_target: CompositeTarget,
         exit_after_load: bool,
         convert_mouse_to_touch: bool,
         top_level_browsing_context_id: TopLevelBrowsingContextId,
+        version_string: String,
     ) -> Self {
         let embedder_coordinates = window.get_coordinates();
         let mut webviews = WebViewManager::default();
@@ -377,7 +384,7 @@ impl<Window: WindowMethods + ?Sized> IOCompositor<Window> {
             .show(top_level_browsing_context_id)
             .expect("Infallible due to add");
 
-        IOCompositor {
+        let compositor = IOCompositor {
             embedder_coordinates: window.get_coordinates(),
             window,
             port: state.receiver,
@@ -415,27 +422,9 @@ impl<Window: WindowMethods + ?Sized> IOCompositor<Window> {
             pending_frames: 0,
             waiting_on_present: false,
             last_animation_tick: Instant::now(),
-        }
-    }
+            version_string,
+        };
 
-    pub fn create(
-        window: Rc<Window>,
-        state: InitialCompositorState,
-        composite_target: CompositeTarget,
-        exit_after_load: bool,
-        convert_mouse_to_touch: bool,
-        top_level_browsing_context_id: TopLevelBrowsingContextId,
-    ) -> Self {
-        let compositor = IOCompositor::new(
-            window,
-            state,
-            composite_target,
-            exit_after_load,
-            convert_mouse_to_touch,
-            top_level_browsing_context_id,
-        );
-
-        // Make sure the GL state is OK
         compositor.assert_gl_framebuffer_complete();
         compositor
     }
@@ -693,6 +682,7 @@ impl<Window: WindowMethods + ?Sized> IOCompositor<Window> {
 
     /// Accept messages from content processes that need to be relayed to the WebRender
     /// instance in the parent process.
+    #[tracing::instrument(skip(self))]
     fn handle_webrender_message(&mut self, msg: ForwardedToCompositorMsg) {
         match msg {
             ForwardedToCompositorMsg::Layout(ScriptToCompositorMsg::SendInitialTransaction(
@@ -780,6 +770,8 @@ impl<Window: WindowMethods + ?Sized> IOCompositor<Window> {
                     display_list_descriptor,
                 );
 
+                let span = span!(Level::TRACE, "ScriptToCompositorMsg::BuiltDisplayList");
+                let _enter = span.enter();
                 let pipeline_id = display_list_info.pipeline_id;
                 let details = self.pipeline_details(pipeline_id.into());
                 details.most_recent_display_list_epoch = Some(display_list_info.epoch);
@@ -1550,6 +1542,7 @@ impl<Window: WindowMethods + ?Sized> IOCompositor<Window> {
             None => return,
         };
 
+        self.cursor_pos = cursor;
         let event = MouseMoveEvent(result.point_in_viewport, Some(result.node.into()), 0);
         let msg = ConstellationMsg::ForwardEvent(result.pipeline_id, event);
         if let Err(e) = self.constellation_chan.send(msg) {
@@ -1807,19 +1800,31 @@ impl<Window: WindowMethods + ?Sized> IOCompositor<Window> {
             ScrollLocation::Start | ScrollLocation::End => scroll_location,
         };
 
-        let hit_test_result = match self.hit_test_at_point(cursor) {
-            Some(result) => result,
-            None => return None,
-        };
+        let hit_test_results =
+            self.hit_test_at_point_with_flags_and_pipeline(cursor, HitTestFlags::FIND_ALL, None);
 
-        let pipeline_details = match self.pipeline_details.get_mut(&hit_test_result.pipeline_id) {
-            Some(details) => details,
-            None => return None,
-        };
-        pipeline_details
-            .scroll_tree
-            .scroll_node_or_ancestor(&hit_test_result.scroll_tree_node, scroll_location)
-            .map(|(external_id, offset)| (hit_test_result.pipeline_id, external_id, offset))
+        // Iterate through all hit test results, processing only the first node of each pipeline.
+        // This is needed to propagate the scroll events from a pipeline representing an iframe to
+        // its ancestor pipelines.
+        let mut previous_pipeline_id = None;
+        for CompositorHitTestResult {
+            pipeline_id,
+            scroll_tree_node,
+            ..
+        } in hit_test_results.iter()
+        {
+            if previous_pipeline_id.replace(pipeline_id) != Some(pipeline_id) {
+                let scroll_result = self
+                    .pipeline_details
+                    .get_mut(pipeline_id)?
+                    .scroll_tree
+                    .scroll_node_or_ancestor(scroll_tree_node, scroll_location);
+                if let Some((external_id, offset)) = scroll_result {
+                    return Some((*pipeline_id, external_id, offset));
+                }
+            }
+        }
+        None
     }
 
     /// If there are any animations running, dispatches appropriate messages to the constellation.
@@ -2053,6 +2058,7 @@ impl<Window: WindowMethods + ?Sized> IOCompositor<Window> {
     /// Returns Ok if composition was performed or Err if it was not possible to composite for some
     /// reason. When the target is [CompositeTarget::SharedMemory], the image is read back from the
     /// GPU and returned as Ok(Some(png::Image)), otherwise we return Ok(None).
+    #[tracing::instrument(skip(self))]
     fn composite_specific_target(
         &mut self,
         target: CompositeTarget,
@@ -2142,10 +2148,7 @@ impl<Window: WindowMethods + ?Sized> IOCompositor<Window> {
         // ones that the paint metrics recorder is expecting. In that case, we get the current
         // time, inform layout about it and remove the pending metric from the list.
         if !self.pending_paint_metrics.is_empty() {
-            let paint_time = SystemTime::now()
-                .duration_since(UNIX_EPOCH)
-                .unwrap_or_default()
-                .as_nanos() as u64;
+            let paint_time = CrossProcessInstant::now();
             let mut to_remove = Vec::new();
             // For each pending paint metrics pipeline id
             for (id, pending_epoch) in &self.pending_paint_metrics {
@@ -2233,7 +2236,7 @@ impl<Window: WindowMethods + ?Sized> IOCompositor<Window> {
                 Some(Image {
                     width: img.width(),
                     height: img.height(),
-                    format: PixelFormat::RGB8,
+                    format: PixelFormat::RGBA8,
                     bytes: ipc::IpcSharedMemory::from_bytes(&img),
                     id: None,
                     cors_status: CorsStatus::Safe,
@@ -2256,7 +2259,7 @@ impl<Window: WindowMethods + ?Sized> IOCompositor<Window> {
                                 FramebufferUintLength::new(width),
                                 FramebufferUintLength::new(height),
                             );
-                            let dynamic_image = DynamicImage::ImageRgb8(img);
+                            let dynamic_image = DynamicImage::ImageRgba8(img);
                             if let Err(e) = dynamic_image.write_to(&mut file, ImageFormat::Png) {
                                 error!("Failed to save {} ({}).", path, e);
                             }
@@ -2268,6 +2271,8 @@ impl<Window: WindowMethods + ?Sized> IOCompositor<Window> {
             },
         };
 
+        let span = span!(Level::TRACE, "ConstellationMsg::ReadyToPresent");
+        let _enter = span.enter();
         // Notify embedder that servo is ready to present.
         // Embedder should call `present` to tell compositor to continue rendering.
         self.waiting_on_present = true;
@@ -2292,7 +2297,10 @@ impl<Window: WindowMethods + ?Sized> IOCompositor<Window> {
             .map(|info| info.framebuffer_id())
     }
 
+    #[tracing::instrument(skip(self))]
     pub fn present(&mut self) {
+        let span = span!(Level::TRACE, "Compositor Present Surface");
+        let _enter = span.enter();
         if let Err(err) = self.rendering_context.present() {
             warn!("Failed to present surface: {:?}", err);
         }
@@ -2354,6 +2362,7 @@ impl<Window: WindowMethods + ?Sized> IOCompositor<Window> {
         );
     }
 
+    #[tracing::instrument(skip(self))]
     pub fn receive_messages(&mut self) -> bool {
         // Check for new messages coming from the other threads in the system.
         let mut compositor_messages = vec![];
@@ -2380,6 +2389,7 @@ impl<Window: WindowMethods + ?Sized> IOCompositor<Window> {
         true
     }
 
+    #[tracing::instrument(skip(self))]
     pub fn perform_updates(&mut self) -> bool {
         if self.shutdown_state == ShutdownState::FinishedShuttingDown {
             return false;
@@ -2476,42 +2486,25 @@ impl<Window: WindowMethods + ?Sized> IOCompositor<Window> {
             .iter()
             .filter_map(|val| {
                 val.as_ref()
-                    .map(|dir| dir.join("capture_webrender").join(&capture_id))
+                    .map(|dir| dir.join("webrender-captures").join(&capture_id))
                     .ok()
             })
-            .find(|val| match create_dir_all(val) {
-                Ok(_) => true,
-                Err(err) => {
-                    eprintln!("Unable to create path '{:?}' for capture: {:?}", &val, err);
-                    false
-                },
-            });
+            .find(|val| create_dir_all(val).is_ok());
 
-        match available_path {
-            Some(capture_path) => {
-                let revision_file_path = capture_path.join("wr.txt");
+        let Some(capture_path) = available_path else {
+            eprintln!("Couldn't create a path for WebRender captures.");
+            return;
+        };
 
-                debug!(
-                    "Trying to save webrender capture under {:?}",
-                    &revision_file_path
-                );
-                self.webrender_api
-                    .save_capture(capture_path, CaptureBits::all());
+        println!("Saving WebRender capture to {capture_path:?}");
+        self.webrender_api
+            .save_capture(capture_path.clone(), CaptureBits::all());
 
-                match File::create(revision_file_path) {
-                    Ok(mut file) => {
-                        let revision = include!(concat!(env!("OUT_DIR"), "/webrender_revision.rs"));
-                        if let Err(err) = write!(&mut file, "{}", revision) {
-                            eprintln!("Unable to write webrender revision: {:?}", err)
-                        }
-                    },
-                    Err(err) => eprintln!(
-                        "Capture triggered, creating webrender revision info skipped: {:?}",
-                        err
-                    ),
-                }
-            },
-            None => eprintln!("Unable to locate path to save captures"),
+        let version_file_path = capture_path.join("servo-version.txt");
+        if let Err(error) = File::create(version_file_path)
+            .and_then(|mut file| write!(file, "{}", self.version_string))
+        {
+            eprintln!("Unable to write servo version for WebRender Capture: {error:?}");
         }
     }
 }

components/compositing/gl.rs

@@ -5,8 +5,8 @@
 use std::rc::Rc;
 
 use gleam::gl::{self, Gl};
-use image::RgbImage;
-use log::trace;
+use image::RgbaImage;
+use log::{trace, warn};
 use servo_geometry::FramebufferUintLength;
 
 pub struct RenderTargetInfo {
@@ -105,7 +105,7 @@ impl RenderTargetInfo {
         y: i32,
         width: FramebufferUintLength,
         height: FramebufferUintLength,
-    ) -> RgbImage {
+    ) -> RgbaImage {
         let width = width.get() as usize;
         let height = height.get() as usize;
         // For some reason, OSMesa fails to render on the 3rd
@@ -121,13 +121,17 @@ impl RenderTargetInfo {
             y,
             width as gl::GLsizei,
             height as gl::GLsizei,
-            gl::RGB,
+            gl::RGBA,
             gl::UNSIGNED_BYTE,
         );
+        let gl_error = self.gl.get_error();
+        if gl_error != gl::NO_ERROR {
+            warn!("GL error code 0x{gl_error:x} set after read_pixels");
+        }
 
         // flip image vertically (texture is upside down)
         let orig_pixels = pixels.clone();
-        let stride = width * 3;
+        let stride = width * 4;
         for y in 0..height {
             let dst_start = y * stride;
             let src_start = (height - y - 1) * stride;
@@ -135,7 +139,7 @@ impl RenderTargetInfo {
             pixels[dst_start..dst_start + stride].clone_from_slice(&src_slice[..stride]);
         }
 
-        RgbImage::from_raw(width as u32, height as u32, pixels).expect("Flipping image failed!")
+        RgbaImage::from_raw(width as u32, height as u32, pixels).expect("Flipping image failed!")
     }
 }
 
@@ -148,3 +152,57 @@ impl Drop for RenderTargetInfo {
         self.gl.delete_framebuffers(&self.framebuffer_ids);
     }
 }
+
+#[cfg(test)]
+mod test {
+    use gleam::gl;
+    use image::Rgba;
+    use servo_geometry::FramebufferUintLength;
+    use surfman::{Connection, ContextAttributeFlags, ContextAttributes, Error, GLApi, GLVersion};
+
+    use super::RenderTargetInfo;
+
+    #[test]
+    #[allow(unsafe_code)]
+    fn test_read_pixels() -> Result<(), Error> {
+        let connection = Connection::new()?;
+        let adapter = connection.create_software_adapter()?;
+        let mut device = connection.create_device(&adapter)?;
+        let context_descriptor = device.create_context_descriptor(&ContextAttributes {
+            version: GLVersion::new(3, 0),
+            flags: ContextAttributeFlags::empty(),
+        })?;
+        let mut context = device.create_context(&context_descriptor, None)?;
+
+        let gl = match connection.gl_api() {
+            GLApi::GL => unsafe { gl::GlFns::load_with(|s| device.get_proc_address(&context, s)) },
+            GLApi::GLES => unsafe {
+                gl::GlesFns::load_with(|s| device.get_proc_address(&context, s))
+            },
+        };
+
+        device.make_context_current(&context)?;
+
+        {
+            const WIDTH: FramebufferUintLength = FramebufferUintLength::new(16);
+            const HEIGHT: FramebufferUintLength = FramebufferUintLength::new(16);
+            let render_target = RenderTargetInfo::new(gl, WIDTH, HEIGHT);
+            render_target.bind();
+            render_target
+                .gl
+                .clear_color(12.0 / 255.0, 34.0 / 255.0, 56.0 / 255.0, 78.0 / 255.0);
+            render_target.gl.clear(gl::COLOR_BUFFER_BIT);
+
+            let img = render_target.read_back_from_gpu(0, 0, WIDTH, HEIGHT);
+            assert_eq!(img.width(), WIDTH.get());
+            assert_eq!(img.height(), HEIGHT.get());
+
+            let expected_pixel: Rgba<u8> = Rgba([12, 34, 56, 78]);
+            assert!(img.pixels().all(|&p| p == expected_pixel));
+        }
+
+        device.destroy_context(&mut context)?;
+
+        Ok(())
+    }
+}

components/compositing/windowing.rs

@@ -12,6 +12,7 @@ use embedder_traits::{EmbedderProxy, EventLoopWaker};
 use euclid::Scale;
 use keyboard_types::KeyboardEvent;
 use libc::c_void;
+use net::protocols::ProtocolRegistry;
 use script_traits::{
     GamepadEvent, MediaSessionActionType, MouseButton, TouchEventType, TouchId, TraversalDirection,
     WheelDelta,
@@ -222,6 +223,17 @@ pub trait EmbedderMethods {
     fn get_user_agent_string(&self) -> Option<String> {
         None
     }
+
+    /// Returns the version string of this embedder.
+    fn get_version_string(&self) -> Option<String> {
+        None
+    }
+
+    /// Returns the protocol handlers implemented by that embedder.
+    /// They will be merged with the default internal ones.
+    fn get_protocol_handlers(&self) -> ProtocolRegistry {
+        ProtocolRegistry::default()
+    }
 }
 
 #[derive(Clone, Copy, Debug)]

components/config/Cargo.toml

@@ -14,7 +14,6 @@ path = "lib.rs"
 embedder_traits = { workspace = true }
 euclid = { workspace = true }
 getopts = { workspace = true }
-lazy_static = { workspace = true }
 log = { workspace = true }
 num_cpus = { workspace = true }
 serde = { workspace = true, features = ["derive"] }
@@ -26,4 +25,4 @@ style_config = { workspace = true }
 url = { workspace = true }
 
 [target.'cfg(not(target_os = "android"))'.dependencies]
-dirs-next = "2.0"
+dirs = "5.0"

components/config/basedir.rs

@@ -15,7 +15,7 @@ use std::path::PathBuf;
     not(target_os = "android")
 ))]
 pub fn default_config_dir() -> Option<PathBuf> {
-    let mut config_dir = ::dirs_next::config_dir().unwrap();
+    let mut config_dir = ::dirs::config_dir().unwrap();
     config_dir.push("servo");
     config_dir.push("default");
     Some(config_dir)
@@ -30,14 +30,14 @@ pub fn default_config_dir() -> Option<PathBuf> {
 pub fn default_config_dir() -> Option<PathBuf> {
     // FIXME: use `config_dir()` ($HOME/Library/Preferences)
     // instead of `data_dir()` ($HOME/Library/Application Support) ?
-    let mut config_dir = ::dirs_next::data_dir().unwrap();
+    let mut config_dir = ::dirs::data_dir().unwrap();
     config_dir.push("Servo");
     Some(config_dir)
 }
 
 #[cfg(target_os = "windows")]
 pub fn default_config_dir() -> Option<PathBuf> {
-    let mut config_dir = ::dirs_next::config_dir().unwrap();
+    let mut config_dir = ::dirs::config_dir().unwrap();
     config_dir.push("Servo");
     Some(config_dir)
 }

components/config/opts.rs

@@ -10,12 +10,11 @@ use std::fs::{self, File};
 use std::io::Read;
 use std::path::{Path, PathBuf};
 use std::sync::atomic::{AtomicBool, Ordering};
-use std::sync::{RwLock, RwLockReadGuard};
+use std::sync::{LazyLock, RwLock, RwLockReadGuard};
 use std::{env, process};
 
 use euclid::Size2D;
 use getopts::{Matches, Options};
-use lazy_static::lazy_static;
 use log::error;
 use serde::{Deserialize, Serialize};
 use servo_geometry::DeviceIndependentPixel;
@@ -735,7 +734,6 @@ pub fn from_cmdline_args(mut opts: Options, args: &[String]) -> ArgumentParsingR
     let legacy_layout = opt_match.opt_present("legacy-layout");
     if legacy_layout {
         set_pref!(layout.legacy_layout, true);
-        set_pref!(layout.flexbox.enabled, true);
     }
 
     let opts = Opts {
@@ -789,9 +787,7 @@ pub enum ArgumentParsingResult {
 // Make Opts available globally. This saves having to clone and pass
 // opts everywhere it is used, which gets particularly cumbersome
 // when passing through the DOM structures.
-lazy_static! {
-    static ref OPTIONS: RwLock<Opts> = RwLock::new(default_opts());
-}
+static OPTIONS: LazyLock<RwLock<Opts>> = LazyLock::new(|| RwLock::new(default_opts()));
 
 pub fn set_options(opts: Opts) {
     MULTIPROCESS.store(opts.multiprocess, Ordering::SeqCst);

components/config/pref_util.rs

@@ -3,7 +3,6 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 use std::collections::HashMap;
-use std::convert::TryInto;
 use std::fmt;
 use std::str::FromStr;
 use std::sync::RwLock;
@@ -158,9 +157,8 @@ impl From<PrefValue> for [f64; 4] {
     fn from(other: PrefValue) -> [f64; 4] {
         match other {
             PrefValue::Array(values) if values.len() == 4 => {
-                let mut f = values.into_iter().map(|v| v.try_into());
-                if f.all(|v| v.is_ok()) {
-                    let f = f.flatten().collect::<Vec<f64>>();
+                let f = values.into_iter().map(Into::into).collect::<Vec<f64>>();
+                if f.len() == 4 {
                     [f[0], f[1], f[2], f[3]]
                 } else {
                     panic!(
@@ -197,16 +195,16 @@ impl fmt::Display for PrefError {
 impl std::error::Error for PrefError {}
 
 pub struct Accessor<P, V> {
-    pub getter: Box<dyn Fn(&P) -> V + Sync>,
+    pub getter: Box<dyn Fn(&P) -> V + Sync + Send>,
     #[allow(clippy::type_complexity)]
-    pub setter: Box<dyn Fn(&mut P, V) + Sync>,
+    pub setter: Box<dyn Fn(&mut P, V) + Sync + Send>,
 }
 
 impl<P, V> Accessor<P, V> {
     pub fn new<G, S>(getter: G, setter: S) -> Self
     where
-        G: Fn(&P) -> V + Sync + 'static,
-        S: Fn(&mut P, V) + Sync + 'static,
+        G: Fn(&P) -> V + Sync + Send + 'static,
+        S: Fn(&mut P, V) + Sync + Send + 'static,
     {
         Accessor {
             getter: Box::new(getter),

components/config/prefs.rs

@@ -5,27 +5,25 @@
 use std::borrow::ToOwned;
 use std::collections::HashMap;
 use std::convert::{TryFrom, TryInto};
+use std::sync::LazyLock;
 
 use embedder_traits::resources::{self, Resource};
 use gen::Prefs;
-use lazy_static::lazy_static;
 use log::warn;
 use serde_json::{self, Value};
 
 use crate::pref_util::Preferences;
 pub use crate::pref_util::{PrefError, PrefValue};
 
-lazy_static! {
-    static ref PREFS: Preferences<'static, Prefs> = {
-        let def_prefs: Prefs = serde_json::from_str(&resources::read_string(Resource::Preferences))
-            .expect("Failed to initialize config preferences.");
-        let result = Preferences::new(def_prefs, &gen::PREF_ACCESSORS);
-        for (key, value) in result.iter() {
-            set_stylo_pref_ref(&key, &value);
-        }
-        result
-    };
-}
+static PREFS: LazyLock<Preferences<'static, Prefs>> = LazyLock::new(|| {
+    let def_prefs: Prefs = serde_json::from_str(&resources::read_string(Resource::Preferences))
+        .expect("Failed to initialize config preferences.");
+    let result = Preferences::new(def_prefs, &gen::PREF_ACCESSORS);
+    for (key, value) in result.iter() {
+        set_stylo_pref_ref(&key, &value);
+    }
+    result
+});
 
 /// A convenience macro for accessing a preference value using its static path.
 /// Passing an invalid path is a compile-time error.
@@ -165,6 +163,14 @@ mod gen {
         std::cmp::max(num_cpus::get() * 3 / 4, 1) as i64
     }
 
+    fn default_font_size() -> i64 {
+        16
+    }
+
+    fn default_monospace_font_size() -> i64 {
+        13
+    }
+
     fn black() -> i64 {
         0x000000
     }
@@ -188,6 +194,23 @@ mod gen {
                     foreground_color: i64,
                 }
             },
+            fonts: {
+                #[serde(default)]
+                default: String,
+                #[serde(default)]
+                serif: String,
+                #[serde(default)]
+                #[serde(rename = "fonts.sans-serif")]
+                sans_serif: String,
+                #[serde(default)]
+                monospace: String,
+                #[serde(default = "default_font_size")]
+                #[serde(rename = "fonts.default-size")]
+                default_size: i64,
+                #[serde(default = "default_monospace_font_size")]
+                #[serde(rename = "fonts.default-monospace-size")]
+                default_monospace_size: i64,
+            },
             css: {
                 animations: {
                     testing: {
@@ -215,6 +238,7 @@ mod gen {
                         enabled: bool,
                     }
                 },
+                allow_scripts_to_close_windows: bool,
                 canvas_capture: {
                     enabled: bool,
                 },
@@ -375,6 +399,9 @@ mod gen {
                     layers: {
                         enabled: bool,
                     },
+                    openxr: {
+                        enabled: bool,
+                    },
                     sessionavailable: bool,
                     #[serde(rename = "dom.webxr.unsafe-assume-user-intent")]
                     unsafe_assume_user_intent: bool,
@@ -483,12 +510,6 @@ mod gen {
                 shared_memory: {
                     enabled: bool,
                 },
-                strict: {
-                    debug: {
-                        enabled: bool,
-                    },
-                    enabled: bool,
-                },
                 throw_on_asmjs_validation_failure: {
                     enabled: bool,
                 },
@@ -551,6 +572,9 @@ mod gen {
                     #[serde(rename = "network.http-cache.disabled")]
                     disabled: bool,
                 },
+                local_directory_listing: {
+                    enabled: bool,
+                },
                 mime: {
                     sniff: bool,
                 }

components/config_plugins/lib.rs

@@ -108,13 +108,12 @@ impl Build {
         let num_prefs = self.path_map.len();
 
         self.output.extend(quote! {
-            lazy_static::lazy_static! {
-                pub static ref #gen_accessors: std::collections::HashMap<String, #accessor_type> = {
+            pub static #gen_accessors: std::sync::LazyLock<std::collections::HashMap<String, #accessor_type>> =
+                std::sync::LazyLock::new(|| {
                     let mut map = std::collections::HashMap::with_capacity(#num_prefs);
                     #(#values)*
                     map
-                };
-            }
+                });
         });
     }
 

components/constellation/Cargo.toml

@@ -33,7 +33,6 @@ ipc-channel = { workspace = true }
 keyboard-types = { workspace = true }
 log = { workspace = true }
 media = { path = "../media" }
-metrics = { path = "../metrics" }
 net = { path = "../net" }
 net_traits = { workspace = true }
 parking_lot = { workspace = true }
@@ -49,6 +48,7 @@ webgpu = { path = "../webgpu" }
 webrender = { workspace = true }
 webrender_api = { workspace = true }
 webrender_traits = { workspace = true }
+tracing = { workspace = true }
 webxr-api = { git = "https://github.com/servo/webxr", features = ["ipc"] }
 
 [target.'cfg(any(target_os="macos", all(not(target_os = "windows"), not(target_os = "ios"), not(target_os="android"), not(target_arch="arm"), not(target_arch="aarch64"))))'.dependencies]

components/constellation/constellation.rs

@@ -152,7 +152,9 @@ use servo_config::{opts, pref};
 use servo_rand::{random, Rng, ServoRng, SliceRandom};
 use servo_url::{Host, ImmutableOrigin, ServoUrl};
 use style_traits::CSSPixel;
-use webgpu::{self, WebGPU, WebGPURequest};
+use tracing::{span, Level};
+use webgpu::swapchain::WGPUImageMap;
+use webgpu::{self, WebGPU, WebGPURequest, WebGPUResponse};
 use webrender::{RenderApi, RenderApiSender};
 use webrender_api::DocumentId;
 use webrender_traits::{WebRenderNetApi, WebRenderScriptApi, WebrenderExternalImageRegistry};
@@ -218,7 +220,7 @@ struct WebrenderWGPU {
     webrender_external_images: Arc<Mutex<WebrenderExternalImageRegistry>>,
 
     /// WebGPU data that supplied to Webrender for rendering
-    wgpu_image_map: Arc<Mutex<HashMap<u64, webgpu::PresentationData>>>,
+    wgpu_image_map: WGPUImageMap,
 }
 
 /// Servo supports multiple top-level browsing contexts or “webviews”, so `Constellation` needs to
@@ -551,7 +553,7 @@ pub struct InitialConstellationState {
     /// User agent string to report in network requests.
     pub user_agent: Cow<'static, str>,
 
-    pub wgpu_image_map: Arc<Mutex<HashMap<u64, webgpu::PresentationData>>>,
+    pub wgpu_image_map: WGPUImageMap,
 }
 
 /// Data needed for webdriver
@@ -881,7 +883,7 @@ where
             .event_loops
             .get(host)
             .ok_or("Trying to get an event-loop from an unknown browsing context group")
-            .map(|event_loop| event_loop.clone())
+            .cloned()
     }
 
     fn set_event_loop(
@@ -1059,7 +1061,6 @@ where
                 .map(|threads| threads.pipeline()),
             webxr_registry: self.webxr_registry.clone(),
             player_context: self.player_context.clone(),
-            event_loop_waker: None,
             user_agent: self.user_agent.clone(),
         });
 
@@ -1332,6 +1333,7 @@ where
         }
     }
 
+    #[tracing::instrument(skip(self))]
     fn handle_request_from_compositor(&mut self, message: FromCompositorMsg) {
         trace_msg_from_compositor!(message, "{message:?}");
         match message {
@@ -1544,6 +1546,8 @@ where
                 self.set_webview_throttled(webview_id, throttled);
             },
             FromCompositorMsg::ReadyToPresent(webview_ids) => {
+                let span = span!(Level::TRACE, "FromCompositorMsg::ReadyToPresent");
+                let _enter = span.enter();
                 self.embedder_proxy
                     .send((None, EmbedderMsg::ReadyToPresent(webview_ids)));
             },
@@ -2069,7 +2073,7 @@ where
         match request {
             FromScriptMsg::RequestAdapter(response_sender, options, ids) => match webgpu_chan {
                 None => {
-                    if let Err(e) = response_sender.send(None) {
+                    if let Err(e) = response_sender.send(WebGPUResponse::None) {
                         warn!("Failed to send request adapter message: {}", e)
                     }
                 },
@@ -2644,6 +2648,7 @@ where
             ipc::channel().expect("Failed to create IPC channel!");
         let (storage_ipc_sender, storage_ipc_receiver) =
             ipc::channel().expect("Failed to create IPC channel!");
+        let mut webgl_threads_receiver = None;
 
         debug!("Exiting core resource threads.");
         if let Err(e) = self
@@ -2710,9 +2715,12 @@ where
         }
 
         if let Some(webgl_threads) = self.webgl_threads.as_ref() {
+            let (sender, receiver) = ipc::channel().expect("Failed to create IPC channel!");
+            webgl_threads_receiver = Some(receiver);
             debug!("Exiting WebGL thread.");
-            if let Err(e) = webgl_threads.exit() {
-                warn!("Exit WebGL Thread failed ({})", e);
+
+            if let Err(e) = webgl_threads.exit(sender) {
+                warn!("Exit WebGL Thread failed ({e})");
             }
         }
 
@@ -2733,6 +2741,14 @@ where
         if let Err(e) = storage_ipc_receiver.recv() {
             warn!("Exit storage thread failed ({:?})", e);
         }
+        if self.webgl_threads.is_some() {
+            if let Err(e) = webgl_threads_receiver
+                .expect("webgl_threads_receiver to be Some")
+                .recv()
+            {
+                warn!("Exit WebGL thread failed ({:?})", e);
+            }
+        }
 
         debug!("Asking compositor to complete shutdown.");
         self.compositor_proxy.send(CompositorMsg::ShutdownComplete);

components/constellation/network_listener.rs

@@ -8,12 +8,12 @@
 
 use base::id::PipelineId;
 use crossbeam_channel::Sender;
-use http::HeaderMap;
+use http::{header, HeaderMap};
 use ipc_channel::ipc;
 use ipc_channel::router::ROUTER;
 use log::warn;
-use net::http_loader::{set_default_accept, set_default_accept_language};
-use net_traits::request::{Destination, Referrer, RequestBuilder};
+use net::http_loader::{set_default_accept_language, DOCUMENT_ACCEPT_HEADER_VALUE};
+use net_traits::request::{Referrer, RequestBuilder};
 use net_traits::response::ResponseInit;
 use net_traits::{
     CoreResourceMsg, FetchChannels, FetchMetadata, FetchResponseMsg, IpcSend, NetworkError,
@@ -66,7 +66,17 @@ impl NetworkListener {
                 None,
             ),
             None => {
-                set_default_accept(Destination::Document, &mut listener.request_builder.headers);
+                if !listener
+                    .request_builder
+                    .headers
+                    .contains_key(header::ACCEPT)
+                {
+                    listener
+                        .request_builder
+                        .headers
+                        .insert(header::ACCEPT, DOCUMENT_ACCEPT_HEADER_VALUE);
+                }
+
                 set_default_accept_language(&mut listener.request_builder.headers);
 
                 CoreResourceMsg::Fetch(

components/constellation/pipeline.rs

@@ -21,7 +21,6 @@ use canvas_traits::webgl::WebGLPipeline;
 use compositing_traits::{CompositionPipeline, CompositorMsg, CompositorProxy};
 use crossbeam_channel::{unbounded, Sender};
 use devtools_traits::{DevtoolsControlMsg, ScriptToDevtoolsControlMsg};
-use embedder_traits::EventLoopWaker;
 use fonts::FontCacheThread;
 use ipc_channel::ipc::{self, IpcReceiver, IpcSender};
 use ipc_channel::router::ROUTER;
@@ -202,9 +201,6 @@ pub struct InitialPipelineState {
     /// Application window's GL Context for Media player
     pub player_context: WindowGLContext,
 
-    /// Mechanism to force the compositor to process events.
-    pub event_loop_waker: Option<Box<dyn EventLoopWaker>>,
-
     /// User agent string to report in network requests.
     pub user_agent: Cow<'static, str>,
 }

components/constellation/timer_scheduler.rs

@@ -64,10 +64,9 @@ impl TimerScheduler {
     /// Handle an incoming timer request.
     pub fn handle_timer_request(&mut self, request: TimerSchedulerMsg) {
         let TimerEventRequest(_, _, _, delay) = request.0;
-        let schedule = Instant::now() + Duration::from_millis(delay.get());
         let event = ScheduledEvent {
             request: request.0,
-            for_time: schedule,
+            for_time: Instant::now() + delay,
         };
         self.0.push(event);
     }

components/constellation/tracing.rs

@@ -237,6 +237,8 @@ mod from_script {
                 Self::OnDevtoolsStarted(..) => target_variant!("OnDevtoolsStarted"),
                 Self::ReadyToPresent(..) => target_variant!("ReadyToPresent"),
                 Self::EventDelivered(..) => target_variant!("EventDelivered"),
+                Self::PlayGamepadHapticEffect(..) => target_variant!("PlayGamepadHapticEffect"),
+                Self::StopGamepadHapticEffect(..) => target_variant!("StopGamepadHapticEffect"),
             }
         }
     }

components/devtools/Cargo.toml

@@ -11,11 +11,11 @@ name = "devtools"
 path = "lib.rs"
 
 [build-dependencies]
-chrono = "0.4"
+chrono = { workspace = true }
 
 [dependencies]
 base = { workspace = true }
-chrono = "0.4"
+chrono = { workspace = true }
 crossbeam-channel = { workspace = true }
 devtools_traits = { workspace = true }
 embedder_traits = { workspace = true }

components/devtools/actors/browsing_context.rs

@@ -2,142 +2,183 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
-//! Liberally derived from the [Firefox JS implementation](http://mxr.mozilla.org/mozilla-central/source/toolkit/devtools/server/actors/webbrowser.js).
+//! Liberally derived from the [Firefox JS implementation](https://searchfox.org/mozilla-central/source/devtools/server/actors/webbrowser.js).
 //! Connection point for remote devtools that wish to investigate a particular Browsing Context's contents.
 //! Supports dynamic attaching and detaching which control notifications of navigation, etc.
 
 use std::cell::{Cell, RefCell};
 use std::collections::HashMap;
 use std::net::TcpStream;
+use std::time::{SystemTime, UNIX_EPOCH};
 
 use base::id::{BrowsingContextId, PipelineId};
-use devtools_traits::DevtoolScriptControlMsg::{self, WantsLiveNotifications};
-use devtools_traits::{DevtoolsPageInfo, NavigationState};
-use ipc_channel::ipc::IpcSender;
+use devtools_traits::DevtoolScriptControlMsg::{self, GetCssDatabase, WantsLiveNotifications};
+use devtools_traits::{ConsoleLog, DevtoolsPageInfo, NavigationState, PageError};
+use ipc_channel::ipc::{self, IpcSender};
 use serde::Serialize;
 use serde_json::{Map, Value};
 
 use crate::actor::{Actor, ActorMessageStatus, ActorRegistry};
-use crate::actors::emulation::EmulationActor;
+use crate::actors::inspector::accessibility::AccessibilityActor;
+use crate::actors::inspector::css_properties::CssPropertiesActor;
 use crate::actors::inspector::InspectorActor;
-use crate::actors::performance::PerformanceActor;
-use crate::actors::profiler::ProfilerActor;
+use crate::actors::reflow::ReflowActor;
 use crate::actors::stylesheets::StyleSheetsActor;
 use crate::actors::tab::TabDescriptorActor;
 use crate::actors::thread::ThreadActor;
-use crate::actors::timeline::TimelineActor;
+use crate::actors::watcher::{SessionContext, SessionContextType, WatcherActor};
 use crate::protocol::JsonPacketStream;
-use crate::StreamId;
+use crate::{EmptyReplyMsg, StreamId};
 
 #[derive(Serialize)]
-struct BrowsingContextTraits {
-    isBrowsingContext: bool,
+struct FrameUpdateReply {
+    from: String,
+    #[serde(rename = "type")]
+    type_: String,
+    frames: Vec<FrameUpdateMsg>,
 }
 
 #[derive(Serialize)]
-struct AttachedTraits {
-    reconfigure: bool,
+#[serde(rename_all = "camelCase")]
+struct FrameUpdateMsg {
+    id: u32,
+    is_top_level: bool,
+    url: String,
+    title: String,
+}
+
+#[derive(Serialize)]
+struct ResourceAvailableReply {
+    from: String,
+    #[serde(rename = "type")]
+    type_: String,
+    resources: Vec<ResourceAvailableMsg>,
+}
+
+#[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
+struct ResourceAvailableMsg {
+    #[serde(rename = "hasNativeConsoleAPI")]
+    has_native_console_api: Option<bool>,
+    name: String,
+    #[serde(rename = "newURI")]
+    new_uri: Option<String>,
+    resource_type: String,
+    time: u64,
+    title: Option<String>,
+    url: Option<String>,
+}
+
+#[derive(Serialize)]
+struct ConsoleMsg {
+    from: String,
+    #[serde(rename = "type")]
+    type_: String,
+    resources: Vec<ConsoleMessageResource>,
+}
+
+#[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
+struct ConsoleMessageResource {
+    message: ConsoleLog,
+    resource_type: String,
+}
+
+#[derive(Serialize)]
+struct PageErrorMsg {
+    from: String,
+    #[serde(rename = "type")]
+    type_: String,
+    resources: Vec<PageErrorResource>,
+}
+
+#[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
+struct PageErrorResource {
+    page_error: PageError,
+    resource_type: String,
+}
+
+#[derive(Serialize)]
+struct TabNavigated {
+    from: String,
+    #[serde(rename = "type")]
+    type_: String,
+    url: String,
+    title: Option<String>,
+    #[serde(rename = "nativeConsoleAPI")]
+    native_console_api: bool,
+    state: String,
+    is_frame_switching: bool,
+}
+
+#[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
+struct BrowsingContextTraits {
     frames: bool,
-    logInPage: bool,
-    canRewind: bool,
+    is_browsing_context: bool,
+    log_in_page: bool,
+    navigation: bool,
+    supports_top_level_target_flag: bool,
     watchpoints: bool,
 }
 
 #[derive(Serialize)]
-struct BrowsingContextAttachedReply {
-    from: String,
-    #[serde(rename = "type")]
-    type_: String,
-    threadActor: String,
-    cacheDisabled: bool,
-    javascriptEnabled: bool,
-    traits: AttachedTraits,
-}
-
-#[derive(Serialize)]
-struct BrowsingContextDetachedReply {
-    from: String,
-    #[serde(rename = "type")]
-    type_: String,
-}
-
-#[derive(Serialize)]
-struct ReconfigureReply {
-    from: String,
-}
-
-#[derive(Serialize)]
-struct ListFramesReply {
-    from: String,
-    frames: Vec<FrameMsg>,
-}
-
-#[derive(Serialize)]
-struct FrameMsg {
-    id: u32,
-    url: String,
-    title: String,
-    parentID: u32,
-}
-
-#[derive(Serialize)]
-struct ListWorkersReply {
-    from: String,
-    workers: Vec<WorkerMsg>,
-}
-
-#[derive(Serialize)]
-struct WorkerMsg {
-    id: u32,
-}
-
-#[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
 pub struct BrowsingContextActorMsg {
     actor: String,
     title: String,
     url: String,
-    outerWindowID: u32,
-    browsingContextId: u32,
-    consoleActor: String,
-    /*emulationActor: String,
-    inspectorActor: String,
-    timelineActor: String,
-    profilerActor: String,
-    performanceActor: String,
-    styleSheetsActor: String,*/
+    #[serde(rename = "outerWindowID")]
+    outer_window_id: u32,
+    #[serde(rename = "browsingContextID")]
+    browsing_context_id: u32,
+    is_top_level_target: bool,
     traits: BrowsingContextTraits,
+    // Implemented actors
+    accessibility_actor: String,
+    console_actor: String,
+    css_properties_actor: String,
+    inspector_actor: String,
+    reflow_actor: String,
+    style_sheets_actor: String,
+    thread_actor: String,
     // Part of the official protocol, but not yet implemented.
-    /*storageActor: String,
-    memoryActor: String,
-    framerateActor: String,
-    reflowActor: String,
-    cssPropertiesActor: String,
-    animationsActor: String,
-    webExtensionInspectedWindowActor: String,
-    accessibilityActor: String,
-    screenshotActor: String,
-    changesActor: String,
-    webSocketActor: String,
-    manifestActor: String,*/
+    // animations_actor: String,
+    // changes_actor: String,
+    // framerate_actor: String,
+    // manifest_actor: String,
+    // memory_actor: String,
+    // network_content_actor: String,
+    // objects_manager: String,
+    // performance_actor: String,
+    // resonsive_actor: String,
+    // storage_actor: String,
+    // tracer_actor: String,
+    // web_extension_inspected_window_actor: String,
+    // web_socket_actor: String,
 }
 
+/// The browsing context actor encompasses all of the other supporting actors when debugging a web
+/// view. To this extent, it contains a watcher actor that helps when communicating with the host,
+/// as well as resource actors that each perform one debugging function.
 pub(crate) struct BrowsingContextActor {
     pub name: String,
     pub title: RefCell<String>,
     pub url: RefCell<String>,
+    pub active_pipeline: Cell<PipelineId>,
+    pub browsing_context_id: BrowsingContextId,
+    pub accessibility: String,
     pub console: String,
-    pub _emulation: String,
-    pub _inspector: String,
-    pub _timeline: String,
-    pub _profiler: String,
-    pub _performance: String,
-    pub _styleSheets: String,
+    pub css_properties: String,
+    pub inspector: String,
+    pub reflow: String,
+    pub style_sheets: String,
     pub thread: String,
     pub _tab: String,
-    pub streams: RefCell<HashMap<StreamId, TcpStream>>,
-    pub browsing_context_id: BrowsingContextId,
-    pub active_pipeline: Cell<PipelineId>,
     pub script_chan: IpcSender<DevtoolScriptControlMsg>,
+    pub streams: RefCell<HashMap<StreamId, TcpStream>>,
+    pub watcher: String,
 }
 
 impl Actor for BrowsingContextActor {
@@ -149,89 +190,17 @@ impl Actor for BrowsingContextActor {
         &self,
         _registry: &ActorRegistry,
         msg_type: &str,
-        msg: &Map<String, Value>,
+        _msg: &Map<String, Value>,
         stream: &mut TcpStream,
-        id: StreamId,
+        _id: StreamId,
     ) -> Result<ActorMessageStatus, ()> {
         Ok(match msg_type {
-            "reconfigure" => {
-                if let Some(options) = msg.get("options").and_then(|o| o.as_object()) {
-                    if let Some(val) = options.get("performReload") {
-                        if val.as_bool().unwrap_or(false) {
-                            let _ = self
-                                .script_chan
-                                .send(DevtoolScriptControlMsg::Reload(self.active_pipeline.get()));
-                        }
-                    }
-                }
-                let _ = stream.write_json_packet(&ReconfigureReply { from: self.name() });
-                ActorMessageStatus::Processed
-            },
-
-            // https://docs.firefox-dev.tools/backend/protocol.html#listing-browser-tabs
-            // (see "To attach to a _targetActor_")
-            "attach" => {
-                let msg = BrowsingContextAttachedReply {
-                    from: self.name(),
-                    type_: "tabAttached".to_owned(),
-                    threadActor: self.thread.clone(),
-                    cacheDisabled: false,
-                    javascriptEnabled: true,
-                    traits: AttachedTraits {
-                        reconfigure: false,
-                        frames: true,
-                        logInPage: false,
-                        canRewind: false,
-                        watchpoints: false,
-                    },
-                };
-
-                if stream.write_json_packet(&msg).is_err() {
-                    return Ok(ActorMessageStatus::Processed);
-                }
-                self.streams
-                    .borrow_mut()
-                    .insert(id, stream.try_clone().unwrap());
-                self.script_chan
-                    .send(WantsLiveNotifications(self.active_pipeline.get(), true))
-                    .unwrap();
-                ActorMessageStatus::Processed
-            },
-
-            "detach" => {
-                let msg = BrowsingContextDetachedReply {
-                    from: self.name(),
-                    type_: "detached".to_owned(),
-                };
-                let _ = stream.write_json_packet(&msg);
-                self.cleanup(id);
-                ActorMessageStatus::Processed
-            },
-
             "listFrames" => {
-                let msg = ListFramesReply {
-                    from: self.name(),
-                    frames: vec![FrameMsg {
-                        //FIXME: shouldn't ignore pipeline namespace field
-                        id: self.active_pipeline.get().index.0.get(),
-                        parentID: 0,
-                        url: self.url.borrow().clone(),
-                        title: self.title.borrow().clone(),
-                    }],
-                };
+                // TODO: Find out what needs to be listed here
+                let msg = EmptyReplyMsg { from: self.name() };
                 let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
-
-            "listWorkers" => {
-                let msg = ListWorkersReply {
-                    from: self.name(),
-                    workers: vec![],
-                };
-                let _ = stream.write_json_packet(&msg);
-                ActorMessageStatus::Processed
-            },
-
             _ => ActorMessageStatus::Ignored,
         })
     }
@@ -255,61 +224,69 @@ impl BrowsingContextActor {
         script_sender: IpcSender<DevtoolScriptControlMsg>,
         actors: &mut ActorRegistry,
     ) -> BrowsingContextActor {
-        let emulation = EmulationActor::new(actors.new_name("emulation"));
-
         let name = actors.new_name("target");
+        let DevtoolsPageInfo { title, url } = page_info;
+
+        let accessibility = AccessibilityActor::new(actors.new_name("accessibility"));
+
+        let properties = (|| {
+            let (properties_sender, properties_receiver) = ipc::channel().ok()?;
+            script_sender.send(GetCssDatabase(properties_sender)).ok()?;
+            properties_receiver.recv().ok()
+        })()
+        .unwrap_or_default();
+        let css_properties = CssPropertiesActor::new(actors.new_name("css-properties"), properties);
 
         let inspector = InspectorActor {
             name: actors.new_name("inspector"),
             walker: RefCell::new(None),
-            pageStyle: RefCell::new(None),
+            page_style: RefCell::new(None),
             highlighter: RefCell::new(None),
             script_chan: script_sender.clone(),
             browsing_context: name.clone(),
         };
 
-        let timeline =
-            TimelineActor::new(actors.new_name("timeline"), pipeline, script_sender.clone());
+        let reflow = ReflowActor::new(actors.new_name("reflow"));
 
-        let profiler = ProfilerActor::new(actors.new_name("profiler"));
-        let performance = PerformanceActor::new(actors.new_name("performance"));
-
-        // the strange switch between styleSheets and stylesheets is due
-        // to an inconsistency in devtools. See Bug #1498893 in bugzilla
-        let styleSheets = StyleSheetsActor::new(actors.new_name("stylesheets"));
-        let thread = ThreadActor::new(actors.new_name("context"));
-
-        let DevtoolsPageInfo { title, url } = page_info;
+        let style_sheets = StyleSheetsActor::new(actors.new_name("stylesheets"));
 
         let tabdesc = TabDescriptorActor::new(actors, name.clone());
 
+        let thread = ThreadActor::new(actors.new_name("thread"));
+
+        let watcher = WatcherActor::new(
+            actors,
+            name.clone(),
+            SessionContext::new(SessionContextType::BrowserElement),
+        );
+
         let target = BrowsingContextActor {
             name,
             script_chan: script_sender,
             title: RefCell::new(title),
             url: RefCell::new(url.into_string()),
+            active_pipeline: Cell::new(pipeline),
+            browsing_context_id: id,
+            accessibility: accessibility.name(),
             console,
-            _emulation: emulation.name(),
-            _inspector: inspector.name(),
-            _timeline: timeline.name(),
-            _profiler: profiler.name(),
-            _performance: performance.name(),
-            _styleSheets: styleSheets.name(),
+            css_properties: css_properties.name(),
+            inspector: inspector.name(),
+            reflow: reflow.name(),
+            streams: RefCell::new(HashMap::new()),
+            style_sheets: style_sheets.name(),
             _tab: tabdesc.name(),
             thread: thread.name(),
-            streams: RefCell::new(HashMap::new()),
-            browsing_context_id: id,
-            active_pipeline: Cell::new(pipeline),
+            watcher: watcher.name(),
         };
 
-        actors.register(Box::new(emulation));
+        actors.register(Box::new(accessibility));
+        actors.register(Box::new(css_properties));
         actors.register(Box::new(inspector));
-        actors.register(Box::new(timeline));
-        actors.register(Box::new(profiler));
-        actors.register(Box::new(performance));
-        actors.register(Box::new(styleSheets));
-        actors.register(Box::new(thread));
+        actors.register(Box::new(reflow));
+        actors.register(Box::new(style_sheets));
         actors.register(Box::new(tabdesc));
+        actors.register(Box::new(thread));
+        actors.register(Box::new(watcher));
 
         target
     }
@@ -318,21 +295,27 @@ impl BrowsingContextActor {
         BrowsingContextActorMsg {
             actor: self.name(),
             traits: BrowsingContextTraits {
-                isBrowsingContext: true,
+                is_browsing_context: true,
+                frames: true,
+                log_in_page: false,
+                navigation: true,
+                supports_top_level_target_flag: true,
+                watchpoints: true,
             },
             title: self.title.borrow().clone(),
             url: self.url.borrow().clone(),
             //FIXME: shouldn't ignore pipeline namespace field
-            browsingContextId: self.browsing_context_id.index.0.get(),
+            browsing_context_id: self.browsing_context_id.index.0.get(),
             //FIXME: shouldn't ignore pipeline namespace field
-            outerWindowID: self.active_pipeline.get().index.0.get(),
-            consoleActor: self.console.clone(),
-            /*emulationActor: self.emulation.clone(),
-            inspectorActor: self.inspector.clone(),
-            timelineActor: self.timeline.clone(),
-            profilerActor: self.profiler.clone(),
-            performanceActor: self.performance.clone(),
-            styleSheetsActor: self.styleSheets.clone(),*/
+            outer_window_id: self.active_pipeline.get().index.0.get(),
+            is_top_level_target: true,
+            accessibility_actor: self.accessibility.clone(),
+            console_actor: self.console.clone(),
+            css_properties_actor: self.css_properties.clone(),
+            inspector_actor: self.inspector.clone(),
+            reflow_actor: self.reflow.clone(),
+            style_sheets_actor: self.style_sheets.clone(),
+            thread_actor: self.thread.clone(),
         }
     }
 
@@ -346,7 +329,7 @@ impl BrowsingContextActor {
         if let Some(p) = pipeline {
             self.active_pipeline.set(p);
         }
-        *self.url.borrow_mut() = url.as_str().to_owned();
+        url.as_str().clone_into(&mut self.url.borrow_mut());
         if let Some(ref t) = title {
             self.title.borrow_mut().clone_from(t);
         }
@@ -356,10 +339,11 @@ impl BrowsingContextActor {
             type_: "tabNavigated".to_owned(),
             url: url.as_str().to_owned(),
             title,
-            nativeConsoleAPI: true,
+            native_console_api: true,
             state: state.to_owned(),
-            isFrameSwitching: false,
+            is_frame_switching: false,
         };
+
         for stream in self.streams.borrow_mut().values_mut() {
             let _ = stream.write_json_packet(&msg);
         }
@@ -371,16 +355,70 @@ impl BrowsingContextActor {
         }
         *self.title.borrow_mut() = title;
     }
-}
 
-#[derive(Serialize)]
-struct TabNavigated {
-    from: String,
-    #[serde(rename = "type")]
-    type_: String,
-    url: String,
-    title: Option<String>,
-    nativeConsoleAPI: bool,
-    state: String,
-    isFrameSwitching: bool,
+    pub(crate) fn frame_update(&self, stream: &mut TcpStream) {
+        let _ = stream.write_json_packet(&FrameUpdateReply {
+            from: self.name(),
+            type_: "frameUpdate".into(),
+            frames: vec![FrameUpdateMsg {
+                id: self.browsing_context_id.index.0.get(),
+                is_top_level: true,
+                title: self.title.borrow().clone(),
+                url: self.url.borrow().clone(),
+            }],
+        });
+    }
+
+    pub(crate) fn document_event(&self, stream: &mut TcpStream) {
+        // TODO: This is a hacky way of sending the 3 messages
+        //       Figure out if there needs work to be done here, ensure the page is loaded
+        for &name in ["dom-loading", "dom-interactive", "dom-complete"].iter() {
+            let _ = stream.write_json_packet(&ResourceAvailableReply {
+                from: self.name(),
+                type_: "resource-available-form".into(),
+                resources: vec![ResourceAvailableMsg {
+                    has_native_console_api: Some(true),
+                    name: name.into(),
+                    new_uri: None,
+                    resource_type: "document-event".into(),
+                    time: SystemTime::now()
+                        .duration_since(UNIX_EPOCH)
+                        .unwrap_or_default()
+                        .as_millis() as u64,
+                    title: Some(self.title.borrow().clone()),
+                    url: Some(self.url.borrow().clone()),
+                }],
+            });
+        }
+    }
+
+    pub(crate) fn console_message(&self, message: ConsoleLog) {
+        let msg = ConsoleMsg {
+            from: self.name(),
+            type_: "resource-available-form".into(),
+            resources: vec![ConsoleMessageResource {
+                message,
+                resource_type: "console-message".into(),
+            }],
+        };
+
+        for stream in self.streams.borrow_mut().values_mut() {
+            let _ = stream.write_json_packet(&msg);
+        }
+    }
+
+    pub(crate) fn page_error(&self, page_error: PageError) {
+        let msg = PageErrorMsg {
+            from: self.name(),
+            type_: "resource-available-form".into(),
+            resources: vec![PageErrorResource {
+                page_error,
+                resource_type: "error-message".into(),
+            }],
+        };
+
+        for stream in self.streams.borrow_mut().values_mut() {
+            let _ = stream.write_json_packet(&msg);
+        }
+    }
 }

components/devtools/actors/console.rs

@@ -16,7 +16,7 @@ use devtools_traits::EvaluateJSReply::{
     ActorValue, BooleanValue, NullValue, NumberValue, StringValue, VoidValue,
 };
 use devtools_traits::{
-    CachedConsoleMessage, CachedConsoleMessageTypes, ConsoleAPI, ConsoleMessage,
+    CachedConsoleMessage, CachedConsoleMessageTypes, ConsoleLog, ConsoleMessage,
     DevtoolScriptControlMsg, LogLevel, PageError,
 };
 use ipc_channel::ipc::{self, IpcSender};
@@ -40,7 +40,7 @@ impl EncodableConsoleMessage for CachedConsoleMessage {
     fn encode(&self) -> serde_json::Result<String> {
         match *self {
             CachedConsoleMessage::PageError(ref a) => serde_json::to_string(a),
-            CachedConsoleMessage::ConsoleAPI(ref a) => serde_json::to_string(a),
+            CachedConsoleMessage::ConsoleLog(ref a) => serde_json::to_string(a),
         }
     }
 }
@@ -49,10 +49,11 @@ impl EncodableConsoleMessage for CachedConsoleMessage {
 struct StartedListenersTraits;
 
 #[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
 struct StartedListenersReply {
     from: String,
-    nativeConsoleAPI: bool,
-    startedListeners: Vec<String>,
+    native_console_api: bool,
+    started_listeners: Vec<String>,
     traits: StartedListenersTraits,
 }
 
@@ -63,46 +64,53 @@ struct GetCachedMessagesReply {
 }
 
 #[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
 struct StopListenersReply {
     from: String,
-    stoppedListeners: Vec<String>,
+    stopped_listeners: Vec<String>,
 }
 
 #[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
 struct AutocompleteReply {
     from: String,
     matches: Vec<String>,
-    matchProp: String,
+    match_prop: String,
 }
 
 #[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
 struct EvaluateJSReply {
     from: String,
     input: String,
     result: Value,
     timestamp: u64,
     exception: Value,
-    exceptionMessage: Value,
-    helperResult: Value,
+    exception_message: Value,
+    helper_result: Value,
 }
 
 #[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
 struct EvaluateJSEvent {
     from: String,
-    r#type: String,
+    #[serde(rename = "type")]
+    type_: String,
     input: String,
     result: Value,
     timestamp: u64,
-    resultID: String,
+    #[serde(rename = "resultID")]
+    result_id: String,
     exception: Value,
-    exceptionMessage: Value,
-    helperResult: Value,
+    exception_message: Value,
+    helper_result: Value,
 }
 
 #[derive(Serialize)]
 struct EvaluateJSAsyncReply {
     from: String,
-    resultID: String,
+    #[serde(rename = "resultID")]
+    result_id: String,
 }
 
 #[derive(Serialize)]
@@ -133,23 +141,6 @@ impl ConsoleActor {
         }
     }
 
-    fn streams_mut(&self, registry: &ActorRegistry, cb: impl Fn(&mut TcpStream)) {
-        match &self.root {
-            Root::BrowsingContext(bc) => registry
-                .find::<BrowsingContextActor>(bc)
-                .streams
-                .borrow_mut()
-                .values_mut()
-                .for_each(cb),
-            Root::DedicatedWorker(worker) => registry
-                .find::<WorkerActor>(worker)
-                .streams
-                .borrow_mut()
-                .values_mut()
-                .for_each(cb),
-        }
-    }
-
     fn current_unique_id(&self, registry: &ActorRegistry) -> UniqueId {
         match &self.root {
             Root::BrowsingContext(bc) => UniqueId::Pipeline(
@@ -162,14 +153,14 @@ impl ConsoleActor {
         }
     }
 
-    fn evaluateJS(
+    fn evaluate_js(
         &self,
         registry: &ActorRegistry,
         msg: &Map<String, Value>,
     ) -> Result<EvaluateJSReply, ()> {
         let input = msg.get("text").unwrap().as_str().unwrap().to_owned();
         let (chan, port) = ipc::channel().unwrap();
-        // FIXME: redesign messages so we don't have to fake pipeline ids when
+        // FIXME: Redesign messages so we don't have to fake pipeline ids when
         //        communicating with workers.
         let pipeline = match self.current_unique_id(registry) {
             UniqueId::Pipeline(p) => p,
@@ -183,7 +174,7 @@ impl ConsoleActor {
             ))
             .unwrap();
 
-        //TODO: extract conversion into protocol module or some other useful place
+        // TODO: Extract conversion into protocol module or some other useful place
         let result = match port.recv().map_err(|_| ())? {
             VoidValue => {
                 let mut m = Map::new();
@@ -219,7 +210,7 @@ impl ConsoleActor {
             },
             StringValue(s) => Value::String(s),
             ActorValue { class, uuid } => {
-                //TODO: make initial ActorValue message include these properties?
+                // TODO: Make initial ActorValue message include these properties?
                 let mut m = Map::new();
                 let actor = ObjectActor::register(registry, uuid);
 
@@ -233,15 +224,18 @@ impl ConsoleActor {
             },
         };
 
-        //TODO: catch and return exception values from JS evaluation
+        // TODO: Catch and return exception values from JS evaluation
         let reply = EvaluateJSReply {
             from: self.name(),
             input,
             result,
-            timestamp: 0,
+            timestamp: SystemTime::now()
+                .duration_since(UNIX_EPOCH)
+                .unwrap_or_default()
+                .as_millis() as u64,
             exception: Value::Null,
-            exceptionMessage: Value::Null,
-            helperResult: Value::Null,
+            exception_message: Value::Null,
+            helper_result: Value::Null,
         };
         std::result::Result::Ok(reply)
     }
@@ -258,14 +252,11 @@ impl ConsoleActor {
             .or_default()
             .push(CachedConsoleMessage::PageError(page_error.clone()));
         if id == self.current_unique_id(registry) {
-            let msg = PageErrorMsg {
-                from: self.name(),
-                type_: "pageError".to_owned(),
-                pageError: page_error,
+            if let Root::BrowsingContext(bc) = &self.root {
+                registry
+                    .find::<BrowsingContextActor>(bc)
+                    .page_error(page_error)
             };
-            self.streams_mut(registry, |stream| {
-                let _ = stream.write_json_packet(&msg);
-            });
         }
     }
 
@@ -275,7 +266,7 @@ impl ConsoleActor {
         id: UniqueId,
         registry: &ActorRegistry,
     ) {
-        let level = match console_message.logLevel {
+        let level = match console_message.log_level {
             LogLevel::Debug => "debug",
             LogLevel::Info => "info",
             LogLevel::Warn => "warn",
@@ -284,42 +275,30 @@ impl ConsoleActor {
             _ => "log",
         }
         .to_owned();
+
+        let console_api = ConsoleLog {
+            level: level.clone(),
+            filename: console_message.filename.clone(),
+            line_number: console_message.line_number as u32,
+            column_number: console_message.column_number as u32,
+            time_stamp: SystemTime::now()
+                .duration_since(UNIX_EPOCH)
+                .unwrap_or_default()
+                .as_millis() as u64,
+            arguments: vec![console_message.message.clone()],
+        };
+
         self.cached_events
             .borrow_mut()
             .entry(id.clone())
             .or_default()
-            .push(CachedConsoleMessage::ConsoleAPI(ConsoleAPI {
-                type_: "ConsoleAPI".to_owned(),
-                level: level.clone(),
-                filename: console_message.filename.clone(),
-                lineNumber: console_message.lineNumber as u32,
-                functionName: "".to_string(), //TODO
-                timeStamp: SystemTime::now()
-                    .duration_since(UNIX_EPOCH)
-                    .unwrap_or_default()
-                    .as_nanos() as u64,
-                private: false,
-                arguments: vec![console_message.message.clone()],
-            }));
+            .push(CachedConsoleMessage::ConsoleLog(console_api.clone()));
         if id == self.current_unique_id(registry) {
-            let msg = ConsoleAPICall {
-                from: self.name(),
-                type_: "consoleAPICall".to_owned(),
-                message: ConsoleMsg {
-                    level,
-                    timeStamp: SystemTime::now()
-                        .duration_since(UNIX_EPOCH)
-                        .unwrap_or_default()
-                        .as_nanos() as u64,
-                    arguments: vec![console_message.message],
-                    filename: console_message.filename,
-                    lineNumber: console_message.lineNumber,
-                    columnNumber: console_message.columnNumber,
-                },
+            if let Root::BrowsingContext(bc) = &self.root {
+                registry
+                    .find::<BrowsingContextActor>(bc)
+                    .console_message(console_api)
             };
-            self.streams_mut(registry, |stream| {
-                let _ = stream.write_json_packet(&msg);
-            });
         }
     }
 }
@@ -377,7 +356,7 @@ impl Actor for ConsoleActor {
                         {
                             true
                         },
-                        CachedConsoleMessage::ConsoleAPI(_)
+                        CachedConsoleMessage::ConsoleLog(_)
                             if message_types.contains(CachedConsoleMessageTypes::CONSOLE_API) =>
                         {
                             true
@@ -404,8 +383,8 @@ impl Actor for ConsoleActor {
                 let listeners = msg.get("listeners").unwrap().as_array().unwrap().to_owned();
                 let msg = StartedListenersReply {
                     from: self.name(),
-                    nativeConsoleAPI: true,
-                    startedListeners: listeners
+                    native_console_api: true,
+                    started_listeners: listeners
                         .into_iter()
                         .map(|s| s.as_str().unwrap().to_owned())
                         .collect(),
@@ -419,7 +398,7 @@ impl Actor for ConsoleActor {
                 //TODO: actually implement listener filters that support starting/stopping
                 let msg = StopListenersReply {
                     from: self.name(),
-                    stoppedListeners: msg
+                    stopped_listeners: msg
                         .get("listeners")
                         .unwrap()
                         .as_array()
@@ -438,23 +417,23 @@ impl Actor for ConsoleActor {
                 let msg = AutocompleteReply {
                     from: self.name(),
                     matches: vec![],
-                    matchProp: "".to_owned(),
+                    match_prop: "".to_owned(),
                 };
                 let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
 
             "evaluateJS" => {
-                let msg = self.evaluateJS(registry, msg);
+                let msg = self.evaluate_js(registry, msg);
                 let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
 
             "evaluateJSAsync" => {
-                let resultID = Uuid::new_v4().to_string();
+                let result_id = Uuid::new_v4().to_string();
                 let early_reply = EvaluateJSAsyncReply {
                     from: self.name(),
-                    resultID: resultID.clone(),
+                    result_id: result_id.clone(),
                 };
                 // Emit an eager reply so that the client starts listening
                 // for an async event with the resultID
@@ -468,17 +447,17 @@ impl Actor for ConsoleActor {
                     return Ok(ActorMessageStatus::Processed);
                 }
 
-                let reply = self.evaluateJS(registry, msg).unwrap();
+                let reply = self.evaluate_js(registry, msg).unwrap();
                 let msg = EvaluateJSEvent {
                     from: self.name(),
-                    r#type: "evaluationResult".to_owned(),
+                    type_: "evaluationResult".to_owned(),
                     input: reply.input,
                     result: reply.result,
                     timestamp: reply.timestamp,
-                    resultID,
+                    result_id,
                     exception: reply.exception,
-                    exceptionMessage: reply.exceptionMessage,
-                    helperResult: reply.helperResult,
+                    exception_message: reply.exception_message,
+                    helper_result: reply.helper_result,
                 };
                 // Send the data from evaluateJS along with a resultID
                 let _ = stream.write_json_packet(&msg);
@@ -498,29 +477,3 @@ impl Actor for ConsoleActor {
         })
     }
 }
-
-#[derive(Serialize)]
-struct ConsoleAPICall {
-    from: String,
-    #[serde(rename = "type")]
-    type_: String,
-    message: ConsoleMsg,
-}
-
-#[derive(Serialize)]
-struct ConsoleMsg {
-    level: String,
-    timeStamp: u64,
-    arguments: Vec<String>,
-    filename: String,
-    lineNumber: usize,
-    columnNumber: usize,
-}
-
-#[derive(Serialize)]
-struct PageErrorMsg {
-    from: String,
-    #[serde(rename = "type")]
-    type_: String,
-    pageError: PageError,
-}

components/devtools/actors/device.rs

@@ -20,6 +20,7 @@ struct GetDescriptionReply {
 // This is only a minimal subset of the properties exposed/expected by Firefox
 // (see https://searchfox.org/mozilla-central/source/devtools/shared/system.js#45)
 #[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
 struct SystemInfo {
     apptype: String,
     // Display version
@@ -30,7 +31,7 @@ struct SystemInfo {
     // Firefox major.minor version number, use for compatibility checks
     platformversion: String,
     // Display name
-    brandName: String,
+    brand_name: String,
 }
 
 include!(concat!(env!("OUT_DIR"), "/build_id.rs"));
@@ -59,8 +60,8 @@ impl Actor for DeviceActor {
                         apptype: "servo".to_string(),
                         version: env!("CARGO_PKG_VERSION").to_string(),
                         appbuildid: BUILD_ID.to_string(),
-                        platformversion: "124.0".to_string(),
-                        brandName: "Servo".to_string(),
+                        platformversion: "125.0".to_string(),
+                        brand_name: "Servo".to_string(),
                     },
                 };
                 let _ = stream.write_json_packet(&msg);
@@ -80,7 +81,7 @@ impl DeviceActor {
     pub fn description() -> ActorDescription {
         ActorDescription {
             category: "actor",
-            typeName: "device",
+            type_name: "device",
             methods: vec![Method {
                 name: "getDescription",
                 request: Value::Null,

components/devtools/actors/emulation.rs

@@ -1,37 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
-
-use std::net::TcpStream;
-
-use serde_json::{Map, Value};
-
-use crate::actor::{Actor, ActorMessageStatus, ActorRegistry};
-use crate::StreamId;
-
-pub struct EmulationActor {
-    pub name: String,
-}
-
-impl Actor for EmulationActor {
-    fn name(&self) -> String {
-        self.name.clone()
-    }
-
-    fn handle_message(
-        &self,
-        _registry: &ActorRegistry,
-        _msg_type: &str,
-        _msg: &Map<String, Value>,
-        _stream: &mut TcpStream,
-        _id: StreamId,
-    ) -> Result<ActorMessageStatus, ()> {
-        Ok(ActorMessageStatus::Ignored)
-    }
-}
-
-impl EmulationActor {
-    pub fn new(name: String) -> EmulationActor {
-        EmulationActor { name }
-    }
-}

components/devtools/actors/framerate.rs

@@ -18,7 +18,6 @@ pub struct FramerateActor {
     name: String,
     pipeline: PipelineId,
     script_sender: IpcSender<DevtoolScriptControlMsg>,
-
     is_recording: bool,
     ticks: Vec<HighResolutionStamp>,
 }
@@ -41,7 +40,7 @@ impl Actor for FramerateActor {
 }
 
 impl FramerateActor {
-    /// return name of actor
+    /// Return name of actor
     pub fn create(
         registry: &ActorRegistry,
         pipeline_id: PipelineId,

components/devtools/actors/inspector.rs

@@ -5,137 +5,38 @@
 //! Liberally derived from the [Firefox JS implementation](http://mxr.mozilla.org/mozilla-central/source/toolkit/devtools/server/actors/inspector.js).
 
 use std::cell::RefCell;
+use std::collections::HashMap;
 use std::net::TcpStream;
 
-use base::id::PipelineId;
-use devtools_traits::DevtoolScriptControlMsg::{
-    GetChildren, GetDocumentElement, GetLayout, GetRootNode, ModifyAttribute,
-};
-use devtools_traits::{ComputedNodeLayout, DevtoolScriptControlMsg, NodeInfo};
+use devtools_traits::DevtoolScriptControlMsg;
+use devtools_traits::DevtoolScriptControlMsg::GetRootNode;
 use ipc_channel::ipc::{self, IpcSender};
 use serde::Serialize;
 use serde_json::{self, Map, Value};
 
 use crate::actor::{Actor, ActorMessageStatus, ActorRegistry};
 use crate::actors::browsing_context::BrowsingContextActor;
+use crate::actors::inspector::highlighter::{HighlighterActor, HighlighterMsg};
+use crate::actors::inspector::node::NodeInfoToProtocol;
+use crate::actors::inspector::page_style::{PageStyleActor, PageStyleMsg};
+use crate::actors::inspector::walker::{WalkerActor, WalkerMsg};
 use crate::protocol::JsonPacketStream;
 use crate::StreamId;
 
-pub struct InspectorActor {
-    pub name: String,
-    pub walker: RefCell<Option<String>>,
-    pub pageStyle: RefCell<Option<String>>,
-    pub highlighter: RefCell<Option<String>>,
-    pub script_chan: IpcSender<DevtoolScriptControlMsg>,
-    pub browsing_context: String,
-}
+pub mod accessibility;
+pub mod css_properties;
+pub mod highlighter;
+pub mod layout;
+pub mod node;
+pub mod page_style;
+pub mod style_rule;
+pub mod walker;
 
 #[derive(Serialize)]
-struct GetHighlighterReply {
-    highligter: HighlighterMsg, // sic.
+#[serde(rename_all = "camelCase")]
+struct GetPageStyleReply {
     from: String,
-}
-
-#[derive(Serialize)]
-struct HighlighterMsg {
-    actor: String,
-}
-
-struct HighlighterActor {
-    name: String,
-}
-
-pub struct NodeActor {
-    pub name: String,
-    script_chan: IpcSender<DevtoolScriptControlMsg>,
-    pipeline: PipelineId,
-}
-
-#[derive(Serialize)]
-struct ShowBoxModelReply {
-    from: String,
-}
-
-#[derive(Serialize)]
-struct HideBoxModelReply {
-    from: String,
-}
-
-impl Actor for HighlighterActor {
-    fn name(&self) -> String {
-        self.name.clone()
-    }
-
-    fn handle_message(
-        &self,
-        _registry: &ActorRegistry,
-        msg_type: &str,
-        _msg: &Map<String, Value>,
-        stream: &mut TcpStream,
-        _id: StreamId,
-    ) -> Result<ActorMessageStatus, ()> {
-        Ok(match msg_type {
-            "showBoxModel" => {
-                let msg = ShowBoxModelReply { from: self.name() };
-                let _ = stream.write_json_packet(&msg);
-                ActorMessageStatus::Processed
-            },
-
-            "hideBoxModel" => {
-                let msg = HideBoxModelReply { from: self.name() };
-                let _ = stream.write_json_packet(&msg);
-                ActorMessageStatus::Processed
-            },
-
-            _ => ActorMessageStatus::Ignored,
-        })
-    }
-}
-
-#[derive(Serialize)]
-struct ModifyAttributeReply {
-    from: String,
-}
-
-impl Actor for NodeActor {
-    fn name(&self) -> String {
-        self.name.clone()
-    }
-
-    fn handle_message(
-        &self,
-        registry: &ActorRegistry,
-        msg_type: &str,
-        msg: &Map<String, Value>,
-        stream: &mut TcpStream,
-        _id: StreamId,
-    ) -> Result<ActorMessageStatus, ()> {
-        Ok(match msg_type {
-            "modifyAttributes" => {
-                let target = msg.get("to").unwrap().as_str().unwrap();
-                let mods = msg.get("modifications").unwrap().as_array().unwrap();
-                let modifications = mods
-                    .iter()
-                    .map(|json_mod| {
-                        serde_json::from_str(&serde_json::to_string(json_mod).unwrap()).unwrap()
-                    })
-                    .collect();
-
-                self.script_chan
-                    .send(ModifyAttribute(
-                        self.pipeline,
-                        registry.actor_to_script(target.to_owned()),
-                        modifications,
-                    ))
-                    .unwrap();
-                let reply = ModifyAttributeReply { from: self.name() };
-                let _ = stream.write_json_packet(&reply);
-                ActorMessageStatus::Processed
-            },
-
-            _ => ActorMessageStatus::Ignored,
-        })
-    }
+    page_style: PageStyleMsg,
 }
 
 #[derive(Serialize)]
@@ -145,452 +46,24 @@ struct GetWalkerReply {
 }
 
 #[derive(Serialize)]
-struct WalkerMsg {
-    actor: String,
-    root: NodeActorMsg,
-}
-
-#[derive(Serialize)]
-struct AttrMsg {
-    namespace: String,
-    name: String,
-    value: String,
-}
-
-#[derive(Serialize)]
-struct NodeActorMsg {
-    actor: String,
-    baseURI: String,
-    parent: String,
-    nodeType: u16,
-    namespaceURI: String,
-    nodeName: String,
-    numChildren: usize,
-
-    name: String,
-    publicId: String,
-    systemId: String,
-
-    attrs: Vec<AttrMsg>,
-
-    pseudoClassLocks: Vec<String>,
-
-    isDisplayed: bool,
-
-    hasEventListeners: bool,
-
-    isDocumentElement: bool,
-
-    shortValue: String,
-    incompleteValue: bool,
-}
-
-trait NodeInfoToProtocol {
-    fn encode(
-        self,
-        actors: &ActorRegistry,
-        display: bool,
-        script_chan: IpcSender<DevtoolScriptControlMsg>,
-        pipeline: PipelineId,
-    ) -> NodeActorMsg;
-}
-
-impl NodeInfoToProtocol for NodeInfo {
-    fn encode(
-        self,
-        actors: &ActorRegistry,
-        display: bool,
-        script_chan: IpcSender<DevtoolScriptControlMsg>,
-        pipeline: PipelineId,
-    ) -> NodeActorMsg {
-        let actor_name = if !actors.script_actor_registered(self.uniqueId.clone()) {
-            let name = actors.new_name("node");
-            let node_actor = NodeActor {
-                name: name.clone(),
-                script_chan,
-                pipeline,
-            };
-            actors.register_script_actor(self.uniqueId, name.clone());
-            actors.register_later(Box::new(node_actor));
-            name
-        } else {
-            actors.script_to_actor(self.uniqueId)
-        };
-
-        NodeActorMsg {
-            actor: actor_name,
-            baseURI: self.baseURI,
-            parent: actors.script_to_actor(self.parent.clone()),
-            nodeType: self.nodeType,
-            namespaceURI: self.namespaceURI,
-            nodeName: self.nodeName,
-            numChildren: self.numChildren,
-
-            name: self.name,
-            publicId: self.publicId,
-            systemId: self.systemId,
-
-            attrs: self
-                .attrs
-                .into_iter()
-                .map(|attr| AttrMsg {
-                    namespace: attr.namespace,
-                    name: attr.name,
-                    value: attr.value,
-                })
-                .collect(),
-
-            pseudoClassLocks: vec![], //TODO get this data from script
-
-            isDisplayed: display,
-
-            hasEventListeners: false, //TODO get this data from script
-
-            isDocumentElement: self.isDocumentElement,
-
-            shortValue: self.shortValue,
-            incompleteValue: self.incompleteValue,
-        }
-    }
-}
-
-struct WalkerActor {
-    name: String,
-    script_chan: IpcSender<DevtoolScriptControlMsg>,
-    pipeline: PipelineId,
-}
-
-#[derive(Serialize)]
-struct QuerySelectorReply {
+struct SupportsHighlightersReply {
     from: String,
+    value: bool,
 }
 
 #[derive(Serialize)]
-struct DocumentElementReply {
+struct GetHighlighterReply {
     from: String,
-    node: NodeActorMsg,
+    highlighter: HighlighterMsg,
 }
 
-#[derive(Serialize)]
-struct ClearPseudoclassesReply {
-    from: String,
-}
-
-#[derive(Serialize)]
-struct ChildrenReply {
-    hasFirst: bool,
-    hasLast: bool,
-    nodes: Vec<NodeActorMsg>,
-    from: String,
-}
-
-impl Actor for WalkerActor {
-    fn name(&self) -> String {
-        self.name.clone()
-    }
-
-    fn handle_message(
-        &self,
-        registry: &ActorRegistry,
-        msg_type: &str,
-        msg: &Map<String, Value>,
-        stream: &mut TcpStream,
-        _id: StreamId,
-    ) -> Result<ActorMessageStatus, ()> {
-        Ok(match msg_type {
-            "querySelector" => {
-                let msg = QuerySelectorReply { from: self.name() };
-                let _ = stream.write_json_packet(&msg);
-                ActorMessageStatus::Processed
-            },
-
-            "documentElement" => {
-                let (tx, rx) = ipc::channel().unwrap();
-                self.script_chan
-                    .send(GetDocumentElement(self.pipeline, tx))
-                    .unwrap();
-                let doc_elem_info = rx.recv().unwrap().ok_or(())?;
-                let node =
-                    doc_elem_info.encode(registry, true, self.script_chan.clone(), self.pipeline);
-
-                let msg = DocumentElementReply {
-                    from: self.name(),
-                    node,
-                };
-                let _ = stream.write_json_packet(&msg);
-                ActorMessageStatus::Processed
-            },
-
-            "clearPseudoClassLocks" => {
-                let msg = ClearPseudoclassesReply { from: self.name() };
-                let _ = stream.write_json_packet(&msg);
-                ActorMessageStatus::Processed
-            },
-
-            "children" => {
-                let target = msg.get("node").unwrap().as_str().unwrap();
-                let (tx, rx) = ipc::channel().unwrap();
-                self.script_chan
-                    .send(GetChildren(
-                        self.pipeline,
-                        registry.actor_to_script(target.to_owned()),
-                        tx,
-                    ))
-                    .unwrap();
-                let children = rx.recv().unwrap().ok_or(())?;
-
-                let msg = ChildrenReply {
-                    hasFirst: true,
-                    hasLast: true,
-                    nodes: children
-                        .into_iter()
-                        .map(|child| {
-                            child.encode(registry, true, self.script_chan.clone(), self.pipeline)
-                        })
-                        .collect(),
-                    from: self.name(),
-                };
-                let _ = stream.write_json_packet(&msg);
-                ActorMessageStatus::Processed
-            },
-
-            _ => ActorMessageStatus::Ignored,
-        })
-    }
-}
-
-#[derive(Serialize)]
-struct GetPageStyleReply {
-    from: String,
-    pageStyle: PageStyleMsg,
-}
-
-#[derive(Serialize)]
-struct PageStyleMsg {
-    actor: String,
-}
-
-struct PageStyleActor {
-    name: String,
-    script_chan: IpcSender<DevtoolScriptControlMsg>,
-    pipeline: PipelineId,
-}
-
-#[derive(Serialize)]
-struct GetAppliedReply {
-    entries: Vec<AppliedEntry>,
-    rules: Vec<AppliedRule>,
-    sheets: Vec<AppliedSheet>,
-    from: String,
-}
-
-#[derive(Serialize)]
-struct GetComputedReply {
-    computed: Vec<u32>, //XXX all css props
-    from: String,
-}
-
-#[derive(Serialize)]
-struct AppliedEntry {
-    rule: String,
-    pseudoElement: Value,
-    isSystem: bool,
-    matchedSelectors: Vec<String>,
-}
-
-#[derive(Serialize)]
-struct AppliedRule {
-    actor: String,
-    #[serde(rename = "type")]
-    type_: String,
-    href: String,
-    cssText: String,
-    line: u32,
-    column: u32,
-    parentStyleSheet: String,
-}
-
-#[derive(Serialize)]
-struct AppliedSheet {
-    actor: String,
-    href: String,
-    nodeHref: String,
-    disabled: bool,
-    title: String,
-    system: bool,
-    styleSheetIndex: isize,
-    ruleCount: usize,
-}
-
-#[derive(Serialize)]
-struct GetLayoutReply {
-    from: String,
-
-    display: String,
-    position: String,
-    #[serde(rename = "z-index")]
-    zIndex: String,
-    #[serde(rename = "box-sizing")]
-    boxSizing: String,
-
-    // Would be nice to use a proper struct, blocked by
-    // https://github.com/serde-rs/serde/issues/43
-    autoMargins: serde_json::value::Value,
-    #[serde(rename = "margin-top")]
-    marginTop: String,
-    #[serde(rename = "margin-right")]
-    marginRight: String,
-    #[serde(rename = "margin-bottom")]
-    marginBottom: String,
-    #[serde(rename = "margin-left")]
-    marginLeft: String,
-
-    #[serde(rename = "border-top-width")]
-    borderTopWidth: String,
-    #[serde(rename = "border-right-width")]
-    borderRightWidth: String,
-    #[serde(rename = "border-bottom-width")]
-    borderBottomWidth: String,
-    #[serde(rename = "border-left-width")]
-    borderLeftWidth: String,
-
-    #[serde(rename = "padding-top")]
-    paddingTop: String,
-    #[serde(rename = "padding-right")]
-    paddingRight: String,
-    #[serde(rename = "padding-bottom")]
-    paddingBottom: String,
-    #[serde(rename = "padding-left")]
-    paddingLeft: String,
-
-    width: f32,
-    height: f32,
-}
-
-impl Actor for PageStyleActor {
-    fn name(&self) -> String {
-        self.name.clone()
-    }
-
-    fn handle_message(
-        &self,
-        registry: &ActorRegistry,
-        msg_type: &str,
-        msg: &Map<String, Value>,
-        stream: &mut TcpStream,
-        _id: StreamId,
-    ) -> Result<ActorMessageStatus, ()> {
-        Ok(match msg_type {
-            "getApplied" => {
-                //TODO: query script for relevant applied styles to node (msg.node)
-                let msg = GetAppliedReply {
-                    entries: vec![],
-                    rules: vec![],
-                    sheets: vec![],
-                    from: self.name(),
-                };
-                let _ = stream.write_json_packet(&msg);
-                ActorMessageStatus::Processed
-            },
-
-            "getComputed" => {
-                //TODO: query script for relevant computed styles on node (msg.node)
-                let msg = GetComputedReply {
-                    computed: vec![],
-                    from: self.name(),
-                };
-                let _ = stream.write_json_packet(&msg);
-                ActorMessageStatus::Processed
-            },
-
-            //TODO: query script for box layout properties of node (msg.node)
-            "getLayout" => {
-                let target = msg.get("node").unwrap().as_str().unwrap();
-                let (tx, rx) = ipc::channel().unwrap();
-                self.script_chan
-                    .send(GetLayout(
-                        self.pipeline,
-                        registry.actor_to_script(target.to_owned()),
-                        tx,
-                    ))
-                    .unwrap();
-                let ComputedNodeLayout {
-                    display,
-                    position,
-                    zIndex,
-                    boxSizing,
-                    autoMargins,
-                    marginTop,
-                    marginRight,
-                    marginBottom,
-                    marginLeft,
-                    borderTopWidth,
-                    borderRightWidth,
-                    borderBottomWidth,
-                    borderLeftWidth,
-                    paddingTop,
-                    paddingRight,
-                    paddingBottom,
-                    paddingLeft,
-                    width,
-                    height,
-                } = rx.recv().unwrap().ok_or(())?;
-
-                let auto_margins = msg
-                    .get("autoMargins")
-                    .and_then(Value::as_bool)
-                    .unwrap_or(false);
-
-                // http://mxr.mozilla.org/mozilla-central/source/toolkit/devtools/server/actors/styles.js
-                let msg = GetLayoutReply {
-                    from: self.name(),
-                    display,
-                    position,
-                    zIndex,
-                    boxSizing,
-                    autoMargins: if auto_margins {
-                        let mut m = Map::new();
-                        let auto = serde_json::value::Value::String("auto".to_owned());
-                        if autoMargins.top {
-                            m.insert("top".to_owned(), auto.clone());
-                        }
-                        if autoMargins.right {
-                            m.insert("right".to_owned(), auto.clone());
-                        }
-                        if autoMargins.bottom {
-                            m.insert("bottom".to_owned(), auto.clone());
-                        }
-                        if autoMargins.left {
-                            m.insert("left".to_owned(), auto);
-                        }
-                        serde_json::value::Value::Object(m)
-                    } else {
-                        serde_json::value::Value::Null
-                    },
-                    marginTop,
-                    marginRight,
-                    marginBottom,
-                    marginLeft,
-                    borderTopWidth,
-                    borderRightWidth,
-                    borderBottomWidth,
-                    borderLeftWidth,
-                    paddingTop,
-                    paddingRight,
-                    paddingBottom,
-                    paddingLeft,
-                    width,
-                    height,
-                };
-                let msg = serde_json::to_string(&msg).unwrap();
-                let msg = serde_json::from_str::<Value>(&msg).unwrap();
-                let _ = stream.write_json_packet(&msg);
-                ActorMessageStatus::Processed
-            },
-
-            _ => ActorMessageStatus::Ignored,
-        })
-    }
+pub struct InspectorActor {
+    pub name: String,
+    pub walker: RefCell<Option<String>>,
+    pub page_style: RefCell<Option<String>>,
+    pub highlighter: RefCell<Option<String>>,
+    pub script_chan: IpcSender<DevtoolScriptControlMsg>,
+    pub browsing_context: String,
 }
 
 impl Actor for InspectorActor {
@@ -610,28 +83,42 @@ impl Actor for InspectorActor {
         let pipeline = browsing_context.active_pipeline.get();
         Ok(match msg_type {
             "getWalker" => {
+                let (tx, rx) = ipc::channel().unwrap();
+                self.script_chan.send(GetRootNode(pipeline, tx)).unwrap();
+                let root_info = rx.recv().unwrap().ok_or(())?;
+
+                let name = self
+                    .walker
+                    .borrow()
+                    .clone()
+                    .unwrap_or_else(|| registry.new_name("walker"));
+
+                let root = root_info.encode(
+                    registry,
+                    false,
+                    self.script_chan.clone(),
+                    pipeline,
+                    name.clone(),
+                );
+
                 if self.walker.borrow().is_none() {
                     let walker = WalkerActor {
-                        name: registry.new_name("walker"),
+                        name,
                         script_chan: self.script_chan.clone(),
                         pipeline,
+                        root_node: root.clone(),
+                        mutations: RefCell::new(vec![]),
                     };
                     let mut walker_name = self.walker.borrow_mut();
                     *walker_name = Some(walker.name());
                     registry.register_later(Box::new(walker));
                 }
 
-                let (tx, rx) = ipc::channel().unwrap();
-                self.script_chan.send(GetRootNode(pipeline, tx)).unwrap();
-                let root_info = rx.recv().unwrap().ok_or(())?;
-
-                let node = root_info.encode(registry, false, self.script_chan.clone(), pipeline);
-
                 let msg = GetWalkerReply {
                     from: self.name(),
                     walker: WalkerMsg {
                         actor: self.walker.borrow().clone().unwrap(),
-                        root: node,
+                        root,
                     },
                 };
                 let _ = stream.write_json_packet(&msg);
@@ -639,31 +126,43 @@ impl Actor for InspectorActor {
             },
 
             "getPageStyle" => {
-                if self.pageStyle.borrow().is_none() {
+                if self.page_style.borrow().is_none() {
                     let style = PageStyleActor {
-                        name: registry.new_name("pageStyle"),
+                        name: registry.new_name("page-style"),
                         script_chan: self.script_chan.clone(),
                         pipeline,
                     };
-                    let mut pageStyle = self.pageStyle.borrow_mut();
-                    *pageStyle = Some(style.name());
+                    let mut page_style = self.page_style.borrow_mut();
+                    *page_style = Some(style.name());
                     registry.register_later(Box::new(style));
                 }
 
                 let msg = GetPageStyleReply {
                     from: self.name(),
-                    pageStyle: PageStyleMsg {
-                        actor: self.pageStyle.borrow().clone().unwrap(),
+                    page_style: PageStyleMsg {
+                        actor: self.page_style.borrow().clone().unwrap(),
+                        traits: HashMap::from([
+                            ("fontStretchLevel4".into(), true),
+                            ("fontStyleLevel4".into(), true),
+                            ("fontVariations".into(), true),
+                            ("fontWeightLevel4".into(), true),
+                        ]),
                     },
                 };
                 let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
 
-            //TODO: this is an old message; try adding highlightable to the root traits instead
-            //      and support getHighlighter instead
-            //"highlight" => {}
-            "getHighlighter" => {
+            "supportsHighlighters" => {
+                let msg = SupportsHighlightersReply {
+                    from: self.name(),
+                    value: true,
+                };
+                let _ = stream.write_json_packet(&msg);
+                ActorMessageStatus::Processed
+            },
+
+            "getHighlighterByType" => {
                 if self.highlighter.borrow().is_none() {
                     let highlighter_actor = HighlighterActor {
                         name: registry.new_name("highlighter"),
@@ -675,7 +174,7 @@ impl Actor for InspectorActor {
 
                 let msg = GetHighlighterReply {
                     from: self.name(),
-                    highligter: HighlighterMsg {
+                    highlighter: HighlighterMsg {
                         actor: self.highlighter.borrow().clone().unwrap(),
                     },
                 };

components/devtools/actors/inspector/accessibility.rs

@@ -0,0 +1,132 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+//! The Accessibility actor is responsible for the Accessibility tab in the DevTools page. Right
+//! now it is a placeholder for future functionality.
+
+use std::net::TcpStream;
+
+use serde::Serialize;
+use serde_json::{Map, Value};
+
+use crate::actor::{Actor, ActorMessageStatus, ActorRegistry};
+use crate::protocol::JsonPacketStream;
+use crate::StreamId;
+
+#[derive(Serialize)]
+struct BootstrapState {
+    enabled: bool,
+}
+
+#[derive(Serialize)]
+struct BootstrapReply {
+    from: String,
+    state: BootstrapState,
+}
+
+#[derive(Serialize)]
+struct GetSimulatorReply {
+    from: String,
+    simulator: ActorMsg,
+}
+
+#[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
+struct AccessibilityTraits {
+    tabbing_order: bool,
+}
+
+#[derive(Serialize)]
+struct GetTraitsReply {
+    from: String,
+    traits: AccessibilityTraits,
+}
+
+#[derive(Serialize)]
+struct ActorMsg {
+    actor: String,
+}
+
+#[derive(Serialize)]
+struct GetWalkerReply {
+    from: String,
+    walker: ActorMsg,
+}
+
+pub struct AccessibilityActor {
+    name: String,
+}
+
+impl Actor for AccessibilityActor {
+    fn name(&self) -> String {
+        self.name.clone()
+    }
+
+    /// The accesibility actor can handle the following messages:
+    ///
+    /// - `bootstrap`: It is required but it doesn't do anything yet
+    ///
+    /// - `getSimulator`: Returns a new Simulator actor
+    ///
+    /// - `getTraits`: Informs the DevTools client about the configuration of the accessibility actor
+    ///
+    /// - `getWalker`: Returns a new AccessibleWalker actor (not to be confused with the general
+    ///   inspector Walker actor)
+    fn handle_message(
+        &self,
+        registry: &ActorRegistry,
+        msg_type: &str,
+        _msg: &Map<String, Value>,
+        stream: &mut TcpStream,
+        _id: StreamId,
+    ) -> Result<ActorMessageStatus, ()> {
+        Ok(match msg_type {
+            "bootstrap" => {
+                let msg = BootstrapReply {
+                    from: self.name(),
+                    state: BootstrapState { enabled: false },
+                };
+                let _ = stream.write_json_packet(&msg);
+                ActorMessageStatus::Processed
+            },
+            "getSimulator" => {
+                // TODO: Create actual simulator
+                let simulator = registry.new_name("simulator");
+                let msg = GetSimulatorReply {
+                    from: self.name(),
+                    simulator: ActorMsg { actor: simulator },
+                };
+                let _ = stream.write_json_packet(&msg);
+                ActorMessageStatus::Processed
+            },
+            "getTraits" => {
+                let msg = GetTraitsReply {
+                    from: self.name(),
+                    traits: AccessibilityTraits {
+                        tabbing_order: true,
+                    },
+                };
+                let _ = stream.write_json_packet(&msg);
+                ActorMessageStatus::Processed
+            },
+            "getWalker" => {
+                // TODO: Create actual accessible walker
+                let walker = registry.new_name("accesiblewalker");
+                let msg = GetWalkerReply {
+                    from: self.name(),
+                    walker: ActorMsg { actor: walker },
+                };
+                let _ = stream.write_json_packet(&msg);
+                ActorMessageStatus::Processed
+            },
+            _ => ActorMessageStatus::Ignored,
+        })
+    }
+}
+
+impl AccessibilityActor {
+    pub fn new(name: String) -> Self {
+        Self { name }
+    }
+}

components/devtools/actors/inspector/css_properties.rs

@@ -0,0 +1,65 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+//! This actor holds a database of available css properties, their supported values and
+//! alternative names
+
+use std::collections::HashMap;
+use std::net::TcpStream;
+
+use devtools_traits::CssDatabaseProperty;
+use serde::Serialize;
+use serde_json::{Map, Value};
+
+use crate::actor::{Actor, ActorMessageStatus, ActorRegistry};
+use crate::protocol::JsonPacketStream;
+use crate::StreamId;
+
+pub struct CssPropertiesActor {
+    name: String,
+    properties: HashMap<String, CssDatabaseProperty>,
+}
+
+#[derive(Serialize)]
+struct GetCssDatabaseReply<'a> {
+    from: String,
+    properties: &'a HashMap<String, CssDatabaseProperty>,
+}
+
+impl Actor for CssPropertiesActor {
+    fn name(&self) -> String {
+        self.name.clone()
+    }
+
+    /// The css properties actor can handle the following messages:
+    ///
+    /// - `getCSSDatabase`: Returns a big list of every supported css property so that the
+    ///   inspector can show the available options
+    fn handle_message(
+        &self,
+        _registry: &ActorRegistry,
+        msg_type: &str,
+        _msg: &Map<String, Value>,
+        stream: &mut TcpStream,
+        _id: StreamId,
+    ) -> Result<ActorMessageStatus, ()> {
+        Ok(match msg_type {
+            "getCSSDatabase" => {
+                let _ = stream.write_json_packet(&GetCssDatabaseReply {
+                    from: self.name(),
+                    properties: &self.properties,
+                });
+
+                ActorMessageStatus::Processed
+            },
+            _ => ActorMessageStatus::Ignored,
+        })
+    }
+}
+
+impl CssPropertiesActor {
+    pub fn new(name: String, properties: HashMap<String, CssDatabaseProperty>) -> Self {
+        Self { name, properties }
+    }
+}

components/devtools/actors/inspector/highlighter.rs

@@ -0,0 +1,69 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+//! Handles highlighting selected DOM nodes in the inspector. At the moment it only replies and
+//! changes nothing on Servo's side.
+
+use std::net::TcpStream;
+
+use serde::Serialize;
+use serde_json::{self, Map, Value};
+
+use crate::actor::{Actor, ActorMessageStatus, ActorRegistry};
+use crate::protocol::JsonPacketStream;
+use crate::{EmptyReplyMsg, StreamId};
+
+#[derive(Serialize)]
+pub struct HighlighterMsg {
+    pub actor: String,
+}
+
+pub struct HighlighterActor {
+    pub name: String,
+}
+
+#[derive(Serialize)]
+struct ShowReply {
+    from: String,
+    value: bool,
+}
+
+impl Actor for HighlighterActor {
+    fn name(&self) -> String {
+        self.name.clone()
+    }
+
+    /// The highligher actor can handle the following messages:
+    ///
+    /// - `show`: Enables highlighting for the selected node
+    ///
+    /// - `hide`: Disables highlighting for the selected node
+    fn handle_message(
+        &self,
+        _registry: &ActorRegistry,
+        msg_type: &str,
+        _msg: &Map<String, Value>,
+        stream: &mut TcpStream,
+        _id: StreamId,
+    ) -> Result<ActorMessageStatus, ()> {
+        Ok(match msg_type {
+            "show" => {
+                let msg = ShowReply {
+                    from: self.name(),
+                    value: true,
+                };
+                let _ = stream.write_json_packet(&msg);
+                ActorMessageStatus::Processed
+            },
+
+            "hide" => {
+                let msg = EmptyReplyMsg { from: self.name() };
+                let _ = stream.write_json_packet(&msg);
+                ActorMessageStatus::Processed
+            },
+
+            _ => ActorMessageStatus::Ignored,
+        })
+    }
+}

components/devtools/actors/inspector/layout.rs

@@ -0,0 +1,88 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+//! The layout actor informs the DevTools client of the layout properties of the document, such as
+//! grids or flexboxes. It acts as a placeholder for now.
+
+use std::net::TcpStream;
+
+use serde::Serialize;
+use serde_json::{Map, Value};
+
+use crate::actor::{Actor, ActorMessageStatus, ActorRegistry};
+use crate::protocol::JsonPacketStream;
+use crate::StreamId;
+
+#[derive(Serialize)]
+pub struct LayoutInspectorActorMsg {
+    actor: String,
+}
+
+pub struct LayoutInspectorActor {
+    name: String,
+}
+
+#[derive(Serialize)]
+pub struct GetGridsReply {
+    from: String,
+    grids: Vec<String>,
+}
+
+#[derive(Serialize)]
+pub struct GetCurrentFlexboxReply {
+    from: String,
+    flexbox: Option<()>,
+}
+
+impl Actor for LayoutInspectorActor {
+    fn name(&self) -> String {
+        self.name.clone()
+    }
+
+    /// The layout inspector actor can handle the following messages:
+    ///
+    /// - `getGrids`: Returns a list of CSS grids, non functional at the moment
+    ///
+    /// - `getCurrentFlexbox`: Returns the active flexbox, non functional at the moment
+    fn handle_message(
+        &self,
+        _registry: &ActorRegistry,
+        msg_type: &str,
+        _msg: &Map<String, Value>,
+        stream: &mut TcpStream,
+        _id: StreamId,
+    ) -> Result<ActorMessageStatus, ()> {
+        Ok(match msg_type {
+            "getGrids" => {
+                let msg = GetGridsReply {
+                    from: self.name(),
+                    // TODO: Actually create a list of grids
+                    grids: vec![],
+                };
+                let _ = stream.write_json_packet(&msg);
+                ActorMessageStatus::Processed
+            },
+            "getCurrentFlexbox" => {
+                let msg = GetCurrentFlexboxReply {
+                    from: self.name(),
+                    // TODO: Create and return the current flexbox object
+                    flexbox: None,
+                };
+                let _ = stream.write_json_packet(&msg);
+                ActorMessageStatus::Processed
+            },
+            _ => ActorMessageStatus::Ignored,
+        })
+    }
+}
+
+impl LayoutInspectorActor {
+    pub fn new(name: String) -> Self {
+        Self { name }
+    }
+
+    pub fn encodable(&self) -> LayoutInspectorActorMsg {
+        LayoutInspectorActorMsg { actor: self.name() }
+    }
+}

components/devtools/actors/inspector/node.rs

@@ -0,0 +1,263 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+//! This actor represents one DOM node. It is created by the Walker actor when it is traversing the
+//! document tree.
+
+use std::cell::RefCell;
+use std::collections::HashMap;
+use std::net::TcpStream;
+
+use base::id::PipelineId;
+use devtools_traits::DevtoolScriptControlMsg::{GetChildren, GetDocumentElement, ModifyAttribute};
+use devtools_traits::{DevtoolScriptControlMsg, NodeInfo};
+use ipc_channel::ipc::{self, IpcSender};
+use serde::Serialize;
+use serde_json::{self, Map, Value};
+
+use crate::actor::{Actor, ActorMessageStatus, ActorRegistry};
+use crate::actors::inspector::walker::WalkerActor;
+use crate::protocol::JsonPacketStream;
+use crate::{EmptyReplyMsg, StreamId};
+
+/// Text node type constant. This is defined again to avoid depending on `script`, where it is defined originally.
+/// See `script::dom::bindings::codegen::Bindings::NodeBinding::NodeConstants`.
+const TEXT_NODE: u16 = 3;
+
+/// The maximum length of a text node for it to appear as an inline child in the inspector.
+const MAX_INLINE_LENGTH: usize = 50;
+
+#[derive(Serialize)]
+struct GetUniqueSelectorReply {
+    from: String,
+    value: String,
+}
+
+#[derive(Clone, Serialize)]
+struct AttrMsg {
+    name: String,
+    value: String,
+}
+
+#[derive(Clone, Serialize)]
+#[serde(rename_all = "camelCase")]
+pub struct NodeActorMsg {
+    pub actor: String,
+    #[serde(rename = "baseURI")]
+    base_uri: String,
+    causes_overflow: bool,
+    container_type: Option<()>,
+    pub display_name: String,
+    display_type: Option<String>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    inline_text_child: Option<Box<NodeActorMsg>>,
+    is_after_pseudo_element: bool,
+    is_anonymous: bool,
+    is_before_pseudo_element: bool,
+    is_direct_shadow_host_child: Option<bool>,
+    is_displayed: bool,
+    #[serde(rename = "isInHTMLDocument")]
+    is_in_html_document: Option<bool>,
+    is_marker_pseudo_element: bool,
+    is_native_anonymous: bool,
+    is_scrollable: bool,
+    is_shadow_root: bool,
+    is_top_level_document: bool,
+    node_name: String,
+    node_type: u16,
+    node_value: Option<String>,
+    pub num_children: usize,
+    #[serde(skip_serializing_if = "String::is_empty")]
+    parent: String,
+    shadow_root_mode: Option<()>,
+    traits: HashMap<String, ()>,
+    attrs: Vec<AttrMsg>,
+}
+
+pub struct NodeActor {
+    name: String,
+    pub script_chan: IpcSender<DevtoolScriptControlMsg>,
+    pub pipeline: PipelineId,
+    pub walker: String,
+    pub style_rules: RefCell<HashMap<(String, usize), String>>,
+}
+
+impl Actor for NodeActor {
+    fn name(&self) -> String {
+        self.name.clone()
+    }
+
+    /// The node actor can handle the following messages:
+    ///
+    /// - `modifyAttributes`: Asks the script to change a value in the attribute of the
+    ///   corresponding node
+    ///
+    /// - `getUniqueSelector`: Returns the display name of this node
+    fn handle_message(
+        &self,
+        registry: &ActorRegistry,
+        msg_type: &str,
+        msg: &Map<String, Value>,
+        stream: &mut TcpStream,
+        _id: StreamId,
+    ) -> Result<ActorMessageStatus, ()> {
+        Ok(match msg_type {
+            "modifyAttributes" => {
+                let mods = msg.get("modifications").ok_or(())?.as_array().ok_or(())?;
+                let modifications: Vec<_> = mods
+                    .iter()
+                    .filter_map(|json_mod| {
+                        serde_json::from_str(&serde_json::to_string(json_mod).ok()?).ok()
+                    })
+                    .collect();
+
+                let walker = registry.find::<WalkerActor>(&self.walker);
+                walker.new_mutations(stream, &self.name, &modifications);
+
+                self.script_chan
+                    .send(ModifyAttribute(
+                        self.pipeline,
+                        registry.actor_to_script(self.name()),
+                        modifications,
+                    ))
+                    .map_err(|_| ())?;
+
+                let reply = EmptyReplyMsg { from: self.name() };
+                let _ = stream.write_json_packet(&reply);
+                ActorMessageStatus::Processed
+            },
+
+            "getUniqueSelector" => {
+                let (tx, rx) = ipc::channel().unwrap();
+                self.script_chan
+                    .send(GetDocumentElement(self.pipeline, tx))
+                    .unwrap();
+                let doc_elem_info = rx.recv().map_err(|_| ())?.ok_or(())?;
+                let node = doc_elem_info.encode(
+                    registry,
+                    true,
+                    self.script_chan.clone(),
+                    self.pipeline,
+                    self.walker.clone(),
+                );
+
+                let msg = GetUniqueSelectorReply {
+                    from: self.name(),
+                    value: node.display_name,
+                };
+                let _ = stream.write_json_packet(&msg);
+                ActorMessageStatus::Processed
+            },
+
+            _ => ActorMessageStatus::Ignored,
+        })
+    }
+}
+
+pub trait NodeInfoToProtocol {
+    fn encode(
+        self,
+        actors: &ActorRegistry,
+        display: bool,
+        script_chan: IpcSender<DevtoolScriptControlMsg>,
+        pipeline: PipelineId,
+        walker: String,
+    ) -> NodeActorMsg;
+}
+
+impl NodeInfoToProtocol for NodeInfo {
+    fn encode(
+        self,
+        actors: &ActorRegistry,
+        display: bool,
+        script_chan: IpcSender<DevtoolScriptControlMsg>,
+        pipeline: PipelineId,
+        walker: String,
+    ) -> NodeActorMsg {
+        let actor = if !actors.script_actor_registered(self.unique_id.clone()) {
+            let name = actors.new_name("node");
+            actors.register_script_actor(self.unique_id, name.clone());
+
+            let node_actor = NodeActor {
+                name: name.clone(),
+                script_chan: script_chan.clone(),
+                pipeline,
+                walker: walker.clone(),
+                style_rules: RefCell::new(HashMap::new()),
+            };
+            actors.register_later(Box::new(node_actor));
+            name
+        } else {
+            actors.script_to_actor(self.unique_id)
+        };
+
+        let name = actors.actor_to_script(actor.clone());
+
+        // If a node only has a single text node as a child whith a small enough text,
+        // return it with this node as an `inlineTextChild`.
+        let inline_text_child = (|| {
+            // TODO: Also return if this node is a flex element.
+            if self.num_children != 1 || self.node_name == "SLOT" {
+                return None;
+            }
+
+            let (tx, rx) = ipc::channel().ok()?;
+            script_chan
+                .send(GetChildren(pipeline, name.clone(), tx))
+                .unwrap();
+            let mut children = rx.recv().ok()??;
+
+            let child = children.pop()?;
+            let msg = child.encode(actors, true, script_chan.clone(), pipeline, walker);
+
+            // If the node child is not a text node, do not represent it inline.
+            if msg.node_type != TEXT_NODE {
+                return None;
+            }
+
+            // If the text node child is too big, do not represent it inline.
+            if msg.node_value.clone().unwrap_or_default().len() > MAX_INLINE_LENGTH {
+                return None;
+            }
+
+            Some(Box::new(msg))
+        })();
+
+        NodeActorMsg {
+            actor,
+            base_uri: self.base_uri,
+            causes_overflow: false,
+            container_type: None,
+            display_name: self.node_name.clone().to_lowercase(),
+            display_type: Some("block".into()),
+            inline_text_child,
+            is_after_pseudo_element: false,
+            is_anonymous: false,
+            is_before_pseudo_element: false,
+            is_direct_shadow_host_child: None,
+            is_displayed: display,
+            is_in_html_document: Some(true),
+            is_marker_pseudo_element: false,
+            is_native_anonymous: false,
+            is_scrollable: false,
+            is_shadow_root: false,
+            is_top_level_document: self.is_top_level_document,
+            node_name: self.node_name,
+            node_type: self.node_type,
+            node_value: self.node_value,
+            num_children: self.num_children,
+            parent: actors.script_to_actor(self.parent.clone()),
+            shadow_root_mode: None,
+            traits: HashMap::new(),
+            attrs: self
+                .attrs
+                .into_iter()
+                .map(|attr| AttrMsg {
+                    name: attr.name,
+                    value: attr.value,
+                })
+                .collect(),
+        }
+    }
+}

components/devtools/actors/inspector/page_style.rs

@@ -0,0 +1,351 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+//! The page style actor is responsible of informing the DevTools client of the different style
+//! properties applied, including the attributes and layout of each element.
+
+use std::collections::hash_map::Entry;
+use std::collections::HashMap;
+use std::iter::once;
+use std::net::TcpStream;
+
+use base::id::PipelineId;
+use devtools_traits::DevtoolScriptControlMsg::{GetLayout, GetSelectors};
+use devtools_traits::{ComputedNodeLayout, DevtoolScriptControlMsg};
+use ipc_channel::ipc::{self, IpcSender};
+use serde::Serialize;
+use serde_json::{self, Map, Value};
+
+use crate::actor::{Actor, ActorMessageStatus, ActorRegistry};
+use crate::actors::inspector::node::NodeActor;
+use crate::actors::inspector::style_rule::{AppliedRule, ComputedDeclaration, StyleRuleActor};
+use crate::actors::inspector::walker::{find_child, WalkerActor};
+use crate::protocol::JsonPacketStream;
+use crate::StreamId;
+
+#[derive(Serialize)]
+struct GetAppliedReply {
+    entries: Vec<AppliedEntry>,
+    from: String,
+}
+
+#[derive(Serialize)]
+struct GetComputedReply {
+    computed: HashMap<String, ComputedDeclaration>,
+    from: String,
+}
+
+#[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
+struct AppliedEntry {
+    rule: AppliedRule,
+    pseudo_element: Option<()>,
+    is_system: bool,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    inherited: Option<String>,
+}
+
+#[derive(Serialize)]
+#[serde(rename_all = "kebab-case")]
+struct GetLayoutReply {
+    from: String,
+
+    display: String,
+    position: String,
+    z_index: String,
+    box_sizing: String,
+
+    // Would be nice to use a proper struct, blocked by
+    // https://github.com/serde-rs/serde/issues/43
+    auto_margins: serde_json::value::Value,
+    margin_top: String,
+    margin_right: String,
+    margin_bottom: String,
+    margin_left: String,
+
+    border_top_width: String,
+    border_right_width: String,
+    border_bottom_width: String,
+    border_left_width: String,
+
+    padding_top: String,
+    padding_right: String,
+    padding_bottom: String,
+    padding_left: String,
+
+    width: f32,
+    height: f32,
+}
+
+#[derive(Serialize)]
+pub struct IsPositionEditableReply {
+    pub from: String,
+    pub value: bool,
+}
+
+#[derive(Serialize)]
+pub struct PageStyleMsg {
+    pub actor: String,
+    pub traits: HashMap<String, bool>,
+}
+
+pub struct PageStyleActor {
+    pub name: String,
+    pub script_chan: IpcSender<DevtoolScriptControlMsg>,
+    pub pipeline: PipelineId,
+}
+
+impl Actor for PageStyleActor {
+    fn name(&self) -> String {
+        self.name.clone()
+    }
+
+    /// The page style actor can handle the following messages:
+    ///
+    /// - `getApplied`: Returns the applied styles for a node, they represent the explicit css
+    /// rules set for them, both in the style attribute and in stylesheets.
+    ///
+    /// - `getComputed`: Returns the computed styles for a node, these include all of the supported
+    /// css properties calculated values.
+    ///
+    /// - `getLayout`: Returns the box layout properties for a node.
+    ///
+    /// - `isPositionEditable`: Informs whether you can change a style property in the inspector.
+    fn handle_message(
+        &self,
+        registry: &ActorRegistry,
+        msg_type: &str,
+        msg: &Map<String, Value>,
+        stream: &mut TcpStream,
+        _id: StreamId,
+    ) -> Result<ActorMessageStatus, ()> {
+        Ok(match msg_type {
+            "getApplied" => self.get_applied(msg, registry, stream)?,
+            "getComputed" => self.get_computed(msg, registry, stream)?,
+            "getLayout" => self.get_layout(msg, registry, stream)?,
+            "isPositionEditable" => self.is_position_editable(stream),
+            _ => ActorMessageStatus::Ignored,
+        })
+    }
+}
+
+impl PageStyleActor {
+    fn get_applied(
+        &self,
+        msg: &Map<String, Value>,
+        registry: &ActorRegistry,
+        stream: &mut TcpStream,
+    ) -> Result<ActorMessageStatus, ()> {
+        let target = msg.get("node").ok_or(())?.as_str().ok_or(())?;
+        let node = registry.find::<NodeActor>(target);
+        let walker = registry.find::<WalkerActor>(&node.walker);
+        let entries: Vec<_> = find_child(
+            &node.script_chan,
+            node.pipeline,
+            target,
+            registry,
+            &walker.root_node.actor,
+            vec![],
+            |msg| msg.actor == target,
+        )
+        .unwrap_or_default()
+        .into_iter()
+        .filter_map(|node| {
+            let inherited = (node.actor != target).then(|| node.actor.clone());
+            let node_actor = registry.find::<NodeActor>(&node.actor);
+
+            // Get the css selectors that match this node present in the currently active stylesheets.
+            let selectors = (|| {
+                let (selectors_sender, selector_receiver) = ipc::channel().ok()?;
+                walker
+                    .script_chan
+                    .send(GetSelectors(
+                        walker.pipeline,
+                        registry.actor_to_script(node.actor.clone()),
+                        selectors_sender,
+                    ))
+                    .ok()?;
+                selector_receiver.recv().ok()?
+            })()
+            .unwrap_or_default();
+
+            // For each selector (plus an empty one that represents the style attribute)
+            // get all of the rules associated with it.
+            let entries =
+                once(("".into(), usize::MAX))
+                    .chain(selectors)
+                    .filter_map(move |selector| {
+                        let rule = match node_actor.style_rules.borrow_mut().entry(selector) {
+                            Entry::Vacant(e) => {
+                                let name = registry.new_name("style-rule");
+                                let actor = StyleRuleActor::new(
+                                    name.clone(),
+                                    node_actor.name(),
+                                    (!e.key().0.is_empty()).then_some(e.key().clone()),
+                                );
+                                let rule = actor.applied(registry)?;
+
+                                registry.register_later(Box::new(actor));
+                                e.insert(name);
+                                rule
+                            },
+                            Entry::Occupied(e) => {
+                                let actor = registry.find::<StyleRuleActor>(e.get());
+                                actor.applied(registry)?
+                            },
+                        };
+                        if inherited.is_some() && rule.declarations.is_empty() {
+                            return None;
+                        }
+
+                        Some(AppliedEntry {
+                            rule,
+                            // TODO: Handle pseudo elements
+                            pseudo_element: None,
+                            is_system: false,
+                            inherited: inherited.clone(),
+                        })
+                    });
+            Some(entries)
+        })
+        .flatten()
+        .collect();
+        let msg = GetAppliedReply {
+            entries,
+            from: self.name(),
+        };
+        let _ = stream.write_json_packet(&msg);
+        Ok(ActorMessageStatus::Processed)
+    }
+
+    fn get_computed(
+        &self,
+        msg: &Map<String, Value>,
+        registry: &ActorRegistry,
+        stream: &mut TcpStream,
+    ) -> Result<ActorMessageStatus, ()> {
+        let target = msg.get("node").ok_or(())?.as_str().ok_or(())?;
+        let node_actor = registry.find::<NodeActor>(target);
+        let computed = (|| match node_actor
+            .style_rules
+            .borrow_mut()
+            .entry(("".into(), usize::MAX))
+        {
+            Entry::Vacant(e) => {
+                let name = registry.new_name("style-rule");
+                let actor = StyleRuleActor::new(name.clone(), target.into(), None);
+                let computed = actor.computed(registry)?;
+                registry.register_later(Box::new(actor));
+                e.insert(name);
+                Some(computed)
+            },
+            Entry::Occupied(e) => {
+                let actor = registry.find::<StyleRuleActor>(e.get());
+                Some(actor.computed(registry)?)
+            },
+        })()
+        .unwrap_or_default();
+        let msg = GetComputedReply {
+            computed,
+            from: self.name(),
+        };
+        let _ = stream.write_json_packet(&msg);
+        Ok(ActorMessageStatus::Processed)
+    }
+
+    fn get_layout(
+        &self,
+        msg: &Map<String, Value>,
+        registry: &ActorRegistry,
+        stream: &mut TcpStream,
+    ) -> Result<ActorMessageStatus, ()> {
+        let target = msg.get("node").ok_or(())?.as_str().ok_or(())?;
+        let (computed_node_sender, computed_node_receiver) = ipc::channel().map_err(|_| ())?;
+        self.script_chan
+            .send(GetLayout(
+                self.pipeline,
+                registry.actor_to_script(target.to_owned()),
+                computed_node_sender,
+            ))
+            .unwrap();
+        let ComputedNodeLayout {
+            display,
+            position,
+            z_index,
+            box_sizing,
+            auto_margins,
+            margin_top,
+            margin_right,
+            margin_bottom,
+            margin_left,
+            border_top_width,
+            border_right_width,
+            border_bottom_width,
+            border_left_width,
+            padding_top,
+            padding_right,
+            padding_bottom,
+            padding_left,
+            width,
+            height,
+        } = computed_node_receiver.recv().map_err(|_| ())?.ok_or(())?;
+        let msg_auto_margins = msg
+            .get("autoMargins")
+            .and_then(Value::as_bool)
+            .unwrap_or(false);
+        let msg = GetLayoutReply {
+            from: self.name(),
+            display,
+            position,
+            z_index,
+            box_sizing,
+            auto_margins: if msg_auto_margins {
+                let mut m = Map::new();
+                let auto = serde_json::value::Value::String("auto".to_owned());
+                if auto_margins.top {
+                    m.insert("top".to_owned(), auto.clone());
+                }
+                if auto_margins.right {
+                    m.insert("right".to_owned(), auto.clone());
+                }
+                if auto_margins.bottom {
+                    m.insert("bottom".to_owned(), auto.clone());
+                }
+                if auto_margins.left {
+                    m.insert("left".to_owned(), auto);
+                }
+                serde_json::value::Value::Object(m)
+            } else {
+                serde_json::value::Value::Null
+            },
+            margin_top,
+            margin_right,
+            margin_bottom,
+            margin_left,
+            border_top_width,
+            border_right_width,
+            border_bottom_width,
+            border_left_width,
+            padding_top,
+            padding_right,
+            padding_bottom,
+            padding_left,
+            width,
+            height,
+        };
+        let msg = serde_json::to_string(&msg).map_err(|_| ())?;
+        let msg = serde_json::from_str::<Value>(&msg).map_err(|_| ())?;
+        let _ = stream.write_json_packet(&msg);
+        Ok(ActorMessageStatus::Processed)
+    }
+
+    fn is_position_editable(&self, stream: &mut TcpStream) -> ActorMessageStatus {
+        let msg = IsPositionEditableReply {
+            from: self.name(),
+            value: false,
+        };
+        let _ = stream.write_json_packet(&msg);
+        ActorMessageStatus::Processed
+    }
+}

components/devtools/actors/inspector/style_rule.rs

@@ -0,0 +1,252 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+//! Liberally derived from <https://searchfox.org/mozilla-central/source/devtools/server/actors/thread-configuration.js>
+//! This actor represents one css rule group from a node, allowing the inspector to view it and change it.
+//! A group is either the html style attribute or one selector from one stylesheet.
+
+use std::collections::HashMap;
+use std::net::TcpStream;
+
+use devtools_traits::DevtoolScriptControlMsg::{
+    GetAttributeStyle, GetComputedStyle, GetDocumentElement, GetStylesheetStyle, ModifyRule,
+};
+use ipc_channel::ipc;
+use serde::Serialize;
+use serde_json::{Map, Value};
+
+use crate::actor::{Actor, ActorMessageStatus, ActorRegistry};
+use crate::actors::inspector::node::NodeActor;
+use crate::actors::inspector::walker::WalkerActor;
+use crate::protocol::JsonPacketStream;
+use crate::StreamId;
+
+const ELEMENT_STYLE_TYPE: u32 = 100;
+
+#[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
+pub struct AppliedRule {
+    actor: String,
+    ancestor_data: Vec<()>,
+    authored_text: String,
+    css_text: String,
+    pub declarations: Vec<AppliedDeclaration>,
+    href: String,
+    #[serde(skip_serializing_if = "Vec::is_empty")]
+    selectors: Vec<String>,
+    #[serde(skip_serializing_if = "Vec::is_empty")]
+    selectors_specificity: Vec<u32>,
+    #[serde(rename = "type")]
+    type_: u32,
+    traits: StyleRuleActorTraits,
+}
+
+#[derive(Serialize)]
+pub struct IsUsed {
+    pub used: bool,
+}
+
+#[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
+pub struct AppliedDeclaration {
+    colon_offsets: Vec<i32>,
+    is_name_valid: bool,
+    is_used: IsUsed,
+    is_valid: bool,
+    name: String,
+    offsets: Vec<i32>,
+    priority: String,
+    terminator: String,
+    value: String,
+}
+
+#[derive(Serialize)]
+pub struct ComputedDeclaration {
+    matched: bool,
+    value: String,
+}
+
+#[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
+pub struct StyleRuleActorTraits {
+    pub can_set_rule_text: bool,
+}
+
+#[derive(Serialize)]
+pub struct StyleRuleActorMsg {
+    from: String,
+    rule: Option<AppliedRule>,
+}
+
+pub struct StyleRuleActor {
+    name: String,
+    node: String,
+    selector: Option<(String, usize)>,
+}
+
+impl Actor for StyleRuleActor {
+    fn name(&self) -> String {
+        self.name.clone()
+    }
+
+    /// The style rule configuration actor can handle the following messages:
+    ///
+    /// - `setRuleText`: Applies a set of modifications to the css rules that this actor manages.
+    /// There is also `modifyProperties`, which has a slightly different API to do the same, but
+    /// this is preferred. Which one the devtools client sends is decided by the `traits` defined
+    /// when returning the list of rules.
+    fn handle_message(
+        &self,
+        registry: &ActorRegistry,
+        msg_type: &str,
+        msg: &Map<String, Value>,
+        stream: &mut TcpStream,
+        _id: StreamId,
+    ) -> Result<ActorMessageStatus, ()> {
+        Ok(match msg_type {
+            "setRuleText" => {
+                // Parse the modifications sent from the client
+                let mods = msg.get("modifications").ok_or(())?.as_array().ok_or(())?;
+                let modifications: Vec<_> = mods
+                    .iter()
+                    .filter_map(|json_mod| {
+                        serde_json::from_str(&serde_json::to_string(json_mod).ok()?).ok()
+                    })
+                    .collect();
+
+                // Query the rule modification
+                let node = registry.find::<NodeActor>(&self.node);
+                let walker = registry.find::<WalkerActor>(&node.walker);
+                walker
+                    .script_chan
+                    .send(ModifyRule(
+                        walker.pipeline,
+                        registry.actor_to_script(self.node.clone()),
+                        modifications,
+                    ))
+                    .map_err(|_| ())?;
+
+                let _ = stream.write_json_packet(&self.encodable(registry));
+                ActorMessageStatus::Processed
+            },
+            _ => ActorMessageStatus::Ignored,
+        })
+    }
+}
+
+impl StyleRuleActor {
+    pub fn new(name: String, node: String, selector: Option<(String, usize)>) -> Self {
+        Self {
+            name,
+            node,
+            selector,
+        }
+    }
+
+    pub fn applied(&self, registry: &ActorRegistry) -> Option<AppliedRule> {
+        let node = registry.find::<NodeActor>(&self.node);
+        let walker = registry.find::<WalkerActor>(&node.walker);
+
+        let (document_sender, document_receiver) = ipc::channel().ok()?;
+        walker
+            .script_chan
+            .send(GetDocumentElement(walker.pipeline, document_sender))
+            .ok()?;
+        let node = document_receiver.recv().ok()??;
+
+        // Gets the style definitions. If there is a selector, query the relevant stylesheet, if
+        // not, this represents the style attribute.
+        let (style_sender, style_receiver) = ipc::channel().ok()?;
+        let req = match &self.selector {
+            Some(selector) => {
+                let (selector, stylesheet) = selector.clone();
+                GetStylesheetStyle(
+                    walker.pipeline,
+                    registry.actor_to_script(self.node.clone()),
+                    selector,
+                    stylesheet,
+                    style_sender,
+                )
+            },
+            None => GetAttributeStyle(
+                walker.pipeline,
+                registry.actor_to_script(self.node.clone()),
+                style_sender,
+            ),
+        };
+        walker.script_chan.send(req).ok()?;
+        let style = style_receiver.recv().ok()??;
+
+        Some(AppliedRule {
+            actor: self.name(),
+            ancestor_data: vec![], // TODO: Fill with hierarchy
+            authored_text: "".into(),
+            css_text: "".into(), // TODO: Specify the css text
+            declarations: style
+                .into_iter()
+                .filter_map(|decl| {
+                    Some(AppliedDeclaration {
+                        colon_offsets: vec![],
+                        is_name_valid: true,
+                        is_used: IsUsed { used: true },
+                        is_valid: true,
+                        name: decl.name,
+                        offsets: vec![], // TODO: Get the source of the declaration
+                        priority: decl.priority,
+                        terminator: "".into(),
+                        value: decl.value,
+                    })
+                })
+                .collect(),
+            href: node.base_uri.clone(),
+            selectors: self.selector.iter().map(|(s, _)| s).cloned().collect(),
+            selectors_specificity: self.selector.iter().map(|_| 1).collect(),
+            type_: ELEMENT_STYLE_TYPE,
+            traits: StyleRuleActorTraits {
+                can_set_rule_text: true,
+            },
+        })
+    }
+
+    pub fn computed(
+        &self,
+        registry: &ActorRegistry,
+    ) -> Option<HashMap<String, ComputedDeclaration>> {
+        let node = registry.find::<NodeActor>(&self.node);
+        let walker = registry.find::<WalkerActor>(&node.walker);
+
+        let (style_sender, style_receiver) = ipc::channel().ok()?;
+        walker
+            .script_chan
+            .send(GetComputedStyle(
+                walker.pipeline,
+                registry.actor_to_script(self.node.clone()),
+                style_sender,
+            ))
+            .ok()?;
+        let style = style_receiver.recv().ok()??;
+
+        Some(
+            style
+                .into_iter()
+                .map(|s| {
+                    (
+                        s.name,
+                        ComputedDeclaration {
+                            matched: true,
+                            value: s.value,
+                        },
+                    )
+                })
+                .collect(),
+        )
+    }
+
+    pub fn encodable(&self, registry: &ActorRegistry) -> StyleRuleActorMsg {
+        StyleRuleActorMsg {
+            from: self.name(),
+            rule: self.applied(registry),
+        }
+    }
+}

components/devtools/actors/inspector/walker.rs

@@ -0,0 +1,341 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+//! The walker actor is responsible for traversing the DOM tree in various ways to create new nodes
+
+use std::cell::RefCell;
+use std::net::TcpStream;
+
+use base::id::PipelineId;
+use devtools_traits::DevtoolScriptControlMsg::{GetChildren, GetDocumentElement};
+use devtools_traits::{AttrModification, DevtoolScriptControlMsg};
+use ipc_channel::ipc::{self, IpcSender};
+use serde::Serialize;
+use serde_json::{self, Map, Value};
+
+use crate::actor::{Actor, ActorMessageStatus, ActorRegistry};
+use crate::actors::inspector::layout::{LayoutInspectorActor, LayoutInspectorActorMsg};
+use crate::actors::inspector::node::{NodeActorMsg, NodeInfoToProtocol};
+use crate::protocol::JsonPacketStream;
+use crate::{EmptyReplyMsg, StreamId};
+
+#[derive(Serialize)]
+pub struct WalkerMsg {
+    pub actor: String,
+    pub root: NodeActorMsg,
+}
+
+pub struct WalkerActor {
+    pub name: String,
+    pub script_chan: IpcSender<DevtoolScriptControlMsg>,
+    pub pipeline: PipelineId,
+    pub root_node: NodeActorMsg,
+    pub mutations: RefCell<Vec<(AttrModification, String)>>,
+}
+
+#[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
+struct QuerySelectorReply {
+    from: String,
+    node: NodeActorMsg,
+    new_parents: Vec<NodeActorMsg>,
+}
+
+#[derive(Serialize)]
+struct DocumentElementReply {
+    from: String,
+    node: NodeActorMsg,
+}
+
+#[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
+struct ChildrenReply {
+    has_first: bool,
+    has_last: bool,
+    nodes: Vec<NodeActorMsg>,
+    from: String,
+}
+
+#[derive(Serialize)]
+struct GetLayoutInspectorReply {
+    actor: LayoutInspectorActorMsg,
+    from: String,
+}
+
+#[derive(Serialize)]
+struct WatchRootNodeReply {
+    #[serde(rename = "type")]
+    type_: String,
+    from: String,
+    node: NodeActorMsg,
+}
+
+#[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
+struct MutationMsg {
+    attribute_name: String,
+    new_value: Option<String>,
+    target: String,
+    #[serde(rename = "type")]
+    type_: String,
+}
+
+#[derive(Serialize)]
+struct GetMutationsReply {
+    from: String,
+    mutations: Vec<MutationMsg>,
+}
+
+#[derive(Serialize)]
+struct GetOffsetParentReply {
+    from: String,
+    node: Option<()>,
+}
+
+#[derive(Serialize)]
+struct NewMutationsReply {
+    from: String,
+    #[serde(rename = "type")]
+    type_: String,
+}
+
+impl Actor for WalkerActor {
+    fn name(&self) -> String {
+        self.name.clone()
+    }
+
+    /// The walker actor can handle the following messages:
+    ///
+    /// - `children`: Returns a list of children nodes of the specified node
+    ///
+    /// - `clearPseudoClassLocks`: Placeholder
+    ///
+    /// - `documentElement`: Returns the base document element node
+    ///
+    /// - `getLayoutInspector`: Returns the Layout inspector actor, placeholder
+    ///
+    /// - `getMutations`: Returns the list of attribute changes since it was last called
+    ///
+    /// - `getOffsetParent`: Placeholder
+    ///
+    /// - `querySelector`: Recursively looks for the specified selector in the tree, reutrning the
+    ///   node and its ascendents
+    fn handle_message(
+        &self,
+        registry: &ActorRegistry,
+        msg_type: &str,
+        msg: &Map<String, Value>,
+        stream: &mut TcpStream,
+        _id: StreamId,
+    ) -> Result<ActorMessageStatus, ()> {
+        Ok(match msg_type {
+            "children" => {
+                let target = msg.get("node").ok_or(())?.as_str().ok_or(())?;
+                let (tx, rx) = ipc::channel().map_err(|_| ())?;
+                self.script_chan
+                    .send(GetChildren(
+                        self.pipeline,
+                        registry.actor_to_script(target.into()),
+                        tx,
+                    ))
+                    .map_err(|_| ())?;
+                let children = rx.recv().map_err(|_| ())?.ok_or(())?;
+
+                let msg = ChildrenReply {
+                    has_first: true,
+                    has_last: true,
+                    nodes: children
+                        .into_iter()
+                        .map(|child| {
+                            child.encode(
+                                registry,
+                                true,
+                                self.script_chan.clone(),
+                                self.pipeline,
+                                self.name(),
+                            )
+                        })
+                        .collect(),
+                    from: self.name(),
+                };
+                let _ = stream.write_json_packet(&msg);
+                ActorMessageStatus::Processed
+            },
+            "clearPseudoClassLocks" => {
+                let msg = EmptyReplyMsg { from: self.name() };
+                let _ = stream.write_json_packet(&msg);
+                ActorMessageStatus::Processed
+            },
+            "documentElement" => {
+                let (tx, rx) = ipc::channel().map_err(|_| ())?;
+                self.script_chan
+                    .send(GetDocumentElement(self.pipeline, tx))
+                    .map_err(|_| ())?;
+                let doc_elem_info = rx.recv().map_err(|_| ())?.ok_or(())?;
+                let node = doc_elem_info.encode(
+                    registry,
+                    true,
+                    self.script_chan.clone(),
+                    self.pipeline,
+                    self.name(),
+                );
+
+                let msg = DocumentElementReply {
+                    from: self.name(),
+                    node,
+                };
+                let _ = stream.write_json_packet(&msg);
+                ActorMessageStatus::Processed
+            },
+            "getLayoutInspector" => {
+                // TODO: Create actual layout inspector actor
+                let layout = LayoutInspectorActor::new(registry.new_name("layout"));
+                let actor = layout.encodable();
+                registry.register_later(Box::new(layout));
+
+                let msg = GetLayoutInspectorReply {
+                    from: self.name(),
+                    actor,
+                };
+                let _ = stream.write_json_packet(&msg);
+                ActorMessageStatus::Processed
+            },
+            "getMutations" => {
+                let msg = GetMutationsReply {
+                    from: self.name(),
+                    mutations: self
+                        .mutations
+                        .borrow_mut()
+                        .drain(..)
+                        .map(|(mutation, target)| MutationMsg {
+                            attribute_name: mutation.attribute_name,
+                            new_value: mutation.new_value,
+                            target,
+                            type_: "attributes".into(),
+                        })
+                        .collect(),
+                };
+                let _ = stream.write_json_packet(&msg);
+                ActorMessageStatus::Processed
+            },
+            "getOffsetParent" => {
+                let msg = GetOffsetParentReply {
+                    from: self.name(),
+                    node: None,
+                };
+                let _ = stream.write_json_packet(&msg);
+                ActorMessageStatus::Processed
+            },
+            "querySelector" => {
+                let selector = msg.get("selector").ok_or(())?.as_str().ok_or(())?;
+                let node = msg.get("node").ok_or(())?.as_str().ok_or(())?;
+                let mut hierarchy = find_child(
+                    &self.script_chan,
+                    self.pipeline,
+                    &self.name,
+                    registry,
+                    node,
+                    vec![],
+                    |msg| msg.display_name == selector,
+                )
+                .map_err(|_| ())?;
+                hierarchy.reverse();
+                let node = hierarchy.pop().ok_or(())?;
+
+                let msg = QuerySelectorReply {
+                    from: self.name(),
+                    node,
+                    new_parents: hierarchy,
+                };
+                let _ = stream.write_json_packet(&msg);
+                ActorMessageStatus::Processed
+            },
+            "watchRootNode" => {
+                let msg = WatchRootNodeReply {
+                    type_: "root-available".into(),
+                    from: self.name(),
+                    node: self.root_node.clone(),
+                };
+                let _ = stream.write_json_packet(&msg);
+
+                let msg = EmptyReplyMsg { from: self.name() };
+                let _ = stream.write_json_packet(&msg);
+                ActorMessageStatus::Processed
+            },
+            _ => ActorMessageStatus::Ignored,
+        })
+    }
+}
+
+impl WalkerActor {
+    pub(crate) fn new_mutations(
+        &self,
+        stream: &mut TcpStream,
+        target: &str,
+        modifications: &[AttrModification],
+    ) {
+        {
+            let mut mutations = self.mutations.borrow_mut();
+            mutations.extend(modifications.iter().cloned().map(|m| (m, target.into())));
+        }
+        let _ = stream.write_json_packet(&NewMutationsReply {
+            from: self.name(),
+            type_: "newMutations".into(),
+        });
+    }
+}
+
+/// Recursively searches for a child with the specified selector
+/// If it is found, returns a list with the child and all of its ancestors.
+/// TODO: Investigate how to cache this to some extent.
+pub fn find_child(
+    script_chan: &IpcSender<DevtoolScriptControlMsg>,
+    pipeline: PipelineId,
+    name: &str,
+    registry: &ActorRegistry,
+    node: &str,
+    mut hierarchy: Vec<NodeActorMsg>,
+    compare_fn: impl Fn(&NodeActorMsg) -> bool + Clone,
+) -> Result<Vec<NodeActorMsg>, Vec<NodeActorMsg>> {
+    let (tx, rx) = ipc::channel().unwrap();
+    script_chan
+        .send(GetChildren(
+            pipeline,
+            registry.actor_to_script(node.into()),
+            tx,
+        ))
+        .unwrap();
+    let children = rx.recv().unwrap().ok_or(vec![])?;
+
+    for child in children {
+        let msg = child.encode(registry, true, script_chan.clone(), pipeline, name.into());
+        if compare_fn(&msg) {
+            hierarchy.push(msg);
+            return Ok(hierarchy);
+        };
+
+        if msg.num_children == 0 {
+            continue;
+        }
+
+        match find_child(
+            script_chan,
+            pipeline,
+            name,
+            registry,
+            &msg.actor,
+            hierarchy,
+            compare_fn.clone(),
+        ) {
+            Ok(mut hierarchy) => {
+                hierarchy.push(msg);
+                return Ok(hierarchy);
+            },
+            Err(e) => {
+                hierarchy = e;
+            },
+        }
+    }
+    Err(hierarchy)
+}

components/devtools/actors/memory.rs

@@ -11,16 +11,18 @@ use crate::actor::{Actor, ActorMessageStatus, ActorRegistry};
 use crate::StreamId;
 
 #[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
 pub struct TimelineMemoryReply {
-    jsObjectSize: u64,
-    jsStringSize: u64,
-    jsOtherSize: u64,
-    domSize: u64,
-    styleSize: u64,
-    otherSize: u64,
-    totalSize: u64,
-    jsMilliseconds: f64,
-    nonJSMilliseconds: f64,
+    js_object_size: u64,
+    js_string_size: u64,
+    js_other_size: u64,
+    dom_size: u64,
+    style_size: u64,
+    other_size: u64,
+    total_size: u64,
+    js_milliseconds: f64,
+    #[serde(rename = "nonJSMilliseconds")]
+    non_js_milliseconds: f64,
 }
 
 pub struct MemoryActor {
@@ -57,17 +59,16 @@ impl MemoryActor {
     }
 
     pub fn measure(&self) -> TimelineMemoryReply {
-        //TODO:
         TimelineMemoryReply {
-            jsObjectSize: 1,
-            jsStringSize: 1,
-            jsOtherSize: 1,
-            domSize: 1,
-            styleSize: 1,
-            otherSize: 1,
-            totalSize: 1,
-            jsMilliseconds: 1.1,
-            nonJSMilliseconds: 1.1,
+            js_object_size: 1,
+            js_string_size: 1,
+            js_other_size: 1,
+            dom_size: 1,
+            style_size: 1,
+            other_size: 1,
+            total_size: 1,
+            js_milliseconds: 1.1,
+            non_js_milliseconds: 1.1,
         }
     }
 }

components/devtools/actors/network_event.rs

@@ -6,7 +6,7 @@
 //! Handles interaction with the remote web console on network events (HTTP requests, responses) in Servo.
 
 use std::net::TcpStream;
-use std::time::{SystemTime, UNIX_EPOCH};
+use std::time::{Duration, SystemTime, UNIX_EPOCH};
 
 use chrono::{Local, LocalResult, TimeZone};
 use devtools_traits::{HttpRequest as DevtoolsHttpRequest, HttpResponse as DevtoolsHttpResponse};
@@ -24,10 +24,10 @@ struct HttpRequest {
     method: Method,
     headers: HeaderMap,
     body: Option<Vec<u8>>,
-    startedDateTime: SystemTime,
-    timeStamp: i64,
-    connect_time: u64,
-    send_time: u64,
+    started_date_time: SystemTime,
+    time_stamp: i64,
+    connect_time: Duration,
+    send_time: Duration,
 }
 
 struct HttpResponse {
@@ -44,13 +44,15 @@ pub struct NetworkEventActor {
 }
 
 #[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
 pub struct EventActor {
     pub actor: String,
     pub url: String,
     pub method: String,
-    pub startedDateTime: String,
-    pub timeStamp: i64,
-    pub isXHR: bool,
+    pub started_date_time: String,
+    pub time_stamp: i64,
+    #[serde(rename = "isXHR")]
+    pub is_xhr: bool,
     pub private: bool,
 }
 
@@ -60,28 +62,31 @@ pub struct ResponseCookiesMsg {
 }
 
 #[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
 pub struct ResponseStartMsg {
-    pub httpVersion: String,
-    pub remoteAddress: String,
-    pub remotePort: u32,
+    pub http_version: String,
+    pub remote_address: String,
+    pub remote_port: u32,
     pub status: String,
-    pub statusText: String,
-    pub headersSize: usize,
-    pub discardResponseBody: bool,
+    pub status_text: String,
+    pub headers_size: usize,
+    pub discard_response_body: bool,
 }
 
 #[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
 pub struct ResponseContentMsg {
-    pub mimeType: String,
-    pub contentSize: u32,
-    pub transferredSize: u32,
-    pub discardResponseBody: bool,
+    pub mime_type: String,
+    pub content_size: u32,
+    pub transferred_size: u32,
+    pub discard_response_body: bool,
 }
 
 #[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
 pub struct ResponseHeadersMsg {
     pub headers: usize,
-    pub headersSize: usize,
+    pub headers_size: usize,
 }
 
 #[derive(Serialize)]
@@ -90,17 +95,19 @@ pub struct RequestCookiesMsg {
 }
 
 #[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
 pub struct RequestHeadersMsg {
     headers: usize,
-    headersSize: usize,
+    headers_size: usize,
 }
 
 #[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
 struct GetRequestHeadersReply {
     from: String,
     headers: Vec<Header>,
-    headerSize: usize,
-    rawHeaders: String,
+    header_size: usize,
+    raw_headers: String,
 }
 
 #[derive(Serialize)]
@@ -110,25 +117,28 @@ struct Header {
 }
 
 #[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
 struct GetResponseHeadersReply {
     from: String,
     headers: Vec<Header>,
-    headerSize: usize,
-    rawHeaders: String,
+    header_size: usize,
+    raw_headers: String,
 }
 
 #[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
 struct GetResponseContentReply {
     from: String,
     content: Option<Vec<u8>>,
-    contentDiscarded: bool,
+    content_discarded: bool,
 }
 
 #[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
 struct GetRequestPostDataReply {
     from: String,
-    postData: Option<Vec<u8>>,
-    postDataDiscarded: bool,
+    post_data: Option<Vec<u8>>,
+    post_data_discarded: bool,
 }
 
 #[derive(Serialize)]
@@ -154,10 +164,11 @@ struct Timings {
 }
 
 #[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
 struct GetEventTimingsReply {
     from: String,
     timings: Timings,
-    totalTime: u64,
+    total_time: u64,
 }
 
 #[derive(Serialize)]
@@ -166,9 +177,10 @@ struct SecurityInfo {
 }
 
 #[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
 struct GetSecurityInfoReply {
     from: String,
-    securityInfo: SecurityInfo,
+    security_info: SecurityInfo,
 }
 
 impl Actor for NetworkEventActor {
@@ -187,12 +199,12 @@ impl Actor for NetworkEventActor {
         Ok(match msg_type {
             "getRequestHeaders" => {
                 let mut headers = Vec::new();
-                let mut rawHeadersString = "".to_owned();
-                let mut headersSize = 0;
+                let mut raw_headers_string = "".to_owned();
+                let mut headers_size = 0;
                 for (name, value) in self.request.headers.iter() {
                     let value = &value.to_str().unwrap().to_string();
-                    rawHeadersString = rawHeadersString + name.as_str() + ":" + &value + "\r\n";
-                    headersSize += name.as_str().len() + value.len();
+                    raw_headers_string = raw_headers_string + name.as_str() + ":" + value + "\r\n";
+                    headers_size += name.as_str().len() + value.len();
                     headers.push(Header {
                         name: name.as_str().to_owned(),
                         value: value.to_owned(),
@@ -201,8 +213,8 @@ impl Actor for NetworkEventActor {
                 let msg = GetRequestHeadersReply {
                     from: self.name(),
                     headers,
-                    headerSize: headersSize,
-                    rawHeaders: rawHeadersString,
+                    header_size: headers_size,
+                    raw_headers: raw_headers_string,
                 };
                 let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
@@ -226,8 +238,8 @@ impl Actor for NetworkEventActor {
             "getRequestPostData" => {
                 let msg = GetRequestPostDataReply {
                     from: self.name(),
-                    postData: self.request.body.clone(),
-                    postDataDiscarded: false,
+                    post_data: self.request.body.clone(),
+                    post_data_discarded: false,
                 };
                 let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
@@ -235,24 +247,24 @@ impl Actor for NetworkEventActor {
             "getResponseHeaders" => {
                 if let Some(ref response_headers) = self.response.headers {
                     let mut headers = vec![];
-                    let mut rawHeadersString = "".to_owned();
-                    let mut headersSize = 0;
+                    let mut raw_headers_string = "".to_owned();
+                    let mut headers_size = 0;
                     for (name, value) in response_headers.iter() {
                         headers.push(Header {
                             name: name.as_str().to_owned(),
                             value: value.to_str().unwrap().to_owned(),
                         });
-                        headersSize += name.as_str().len() + value.len();
-                        rawHeadersString.push_str(name.as_str());
-                        rawHeadersString.push(':');
-                        rawHeadersString.push_str(value.to_str().unwrap());
-                        rawHeadersString.push_str("\r\n");
+                        headers_size += name.as_str().len() + value.len();
+                        raw_headers_string.push_str(name.as_str());
+                        raw_headers_string.push(':');
+                        raw_headers_string.push_str(value.to_str().unwrap());
+                        raw_headers_string.push_str("\r\n");
                     }
                     let msg = GetResponseHeadersReply {
                         from: self.name(),
                         headers,
-                        headerSize: headersSize,
-                        rawHeaders: rawHeadersString,
+                        header_size: headers_size,
+                        raw_headers: raw_headers_string,
                     };
                     let _ = stream.write_json_packet(&msg);
                 }
@@ -278,27 +290,27 @@ impl Actor for NetworkEventActor {
                 let msg = GetResponseContentReply {
                     from: self.name(),
                     content: self.response.body.clone(),
-                    contentDiscarded: self.response.body.is_none(),
+                    content_discarded: self.response.body.is_none(),
                 };
                 let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
             },
             "getEventTimings" => {
                 // TODO: This is a fake timings msg
-                let timingsObj = Timings {
+                let timings_obj = Timings {
                     blocked: 0,
                     dns: 0,
-                    connect: self.request.connect_time,
-                    send: self.request.send_time,
+                    connect: self.request.connect_time.as_millis() as u64,
+                    send: self.request.send_time.as_millis() as u64,
                     wait: 0,
                     receive: 0,
                 };
-                let total = timingsObj.connect + timingsObj.send;
+                let total = timings_obj.connect + timings_obj.send;
                 // TODO: Send the correct values for all these fields.
                 let msg = GetEventTimingsReply {
                     from: self.name(),
-                    timings: timingsObj,
-                    totalTime: total,
+                    timings: timings_obj,
+                    total_time: total,
                 };
                 let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
@@ -307,7 +319,7 @@ impl Actor for NetworkEventActor {
                 // TODO: Send the correct values for securityInfo.
                 let msg = GetSecurityInfoReply {
                     from: self.name(),
-                    securityInfo: SecurityInfo {
+                    security_info: SecurityInfo {
                         state: "insecure".to_owned(),
                     },
                 };
@@ -328,13 +340,13 @@ impl NetworkEventActor {
                 method: Method::GET,
                 headers: HeaderMap::new(),
                 body: None,
-                startedDateTime: SystemTime::now(),
-                timeStamp: SystemTime::now()
+                started_date_time: SystemTime::now(),
+                time_stamp: SystemTime::now()
                     .duration_since(UNIX_EPOCH)
                     .unwrap_or_default()
                     .as_secs() as i64,
-                send_time: 0,
-                connect_time: 0,
+                send_time: Duration::ZERO,
+                connect_time: Duration::ZERO,
             },
             response: HttpResponse {
                 headers: None,
@@ -346,13 +358,13 @@ impl NetworkEventActor {
     }
 
     pub fn add_request(&mut self, request: DevtoolsHttpRequest) {
-        self.request.url = request.url.as_str().to_owned();
+        request.url.as_str().clone_into(&mut self.request.url);
 
         self.request.method = request.method.clone();
         self.request.headers = request.headers.clone();
         self.request.body = request.body;
-        self.request.startedDateTime = request.startedDateTime;
-        self.request.timeStamp = request.timeStamp;
+        self.request.started_date_time = request.started_date_time;
+        self.request.time_stamp = request.time_stamp;
         self.request.connect_time = request.connect_time;
         self.request.send_time = request.send_time;
         self.is_xhr = request.is_xhr;
@@ -372,31 +384,31 @@ impl NetworkEventActor {
 
         let started_datetime_rfc3339 = match Local.timestamp_millis_opt(
             self.request
-                .startedDateTime
+                .started_date_time
                 .duration_since(UNIX_EPOCH)
                 .unwrap_or_default()
                 .as_millis() as i64,
         ) {
             LocalResult::None => "".to_owned(),
-            LocalResult::Single(dateTime) => dateTime.to_rfc3339().to_string(),
-            LocalResult::Ambiguous(dateTime, _) => dateTime.to_rfc3339().to_string(),
+            LocalResult::Single(date_time) => date_time.to_rfc3339().to_string(),
+            LocalResult::Ambiguous(date_time, _) => date_time.to_rfc3339().to_string(),
         };
 
         EventActor {
             actor: self.name(),
             url: self.request.url.clone(),
             method: format!("{}", self.request.method),
-            startedDateTime: started_datetime_rfc3339,
-            timeStamp: self.request.timeStamp,
-            isXHR: self.is_xhr,
+            started_date_time: started_datetime_rfc3339,
+            time_stamp: self.request.time_stamp,
+            is_xhr: self.is_xhr,
             private: false,
         }
     }
 
     pub fn response_start(&self) -> ResponseStartMsg {
         // TODO: Send the correct values for all these fields.
-        let hSizeOption = self.response.headers.as_ref().map(|headers| headers.len());
-        let hSize = hSizeOption.unwrap_or(0);
+        let h_size_option = self.response.headers.as_ref().map(|headers| headers.len());
+        let h_size = h_size_option.unwrap_or(0);
         let (status_code, status_message) = self
             .response
             .status
@@ -406,30 +418,30 @@ impl NetworkEventActor {
             });
         // TODO: Send the correct values for remoteAddress and remotePort and http_version.
         ResponseStartMsg {
-            httpVersion: "HTTP/1.1".to_owned(),
-            remoteAddress: "63.245.217.43".to_owned(),
-            remotePort: 443,
+            http_version: "HTTP/1.1".to_owned(),
+            remote_address: "63.245.217.43".to_owned(),
+            remote_port: 443,
             status: status_code.to_string(),
-            statusText: status_message,
-            headersSize: hSize,
-            discardResponseBody: false,
+            status_text: status_message,
+            headers_size: h_size,
+            discard_response_body: false,
         }
     }
 
     pub fn response_content(&self) -> ResponseContentMsg {
-        let mut mString = "".to_owned();
+        let mut m_string = "".to_owned();
         if let Some(ref headers) = self.response.headers {
-            mString = match headers.typed_get::<ContentType>() {
+            m_string = match headers.typed_get::<ContentType>() {
                 Some(ct) => ct.to_string(),
                 _ => "".to_owned(),
             };
         }
         // TODO: Set correct values when response's body is sent to the devtools in http_loader.
         ResponseContentMsg {
-            mimeType: mString,
-            contentSize: 0,
-            transferredSize: 0,
-            discardResponseBody: true,
+            mime_type: m_string,
+            content_size: 0,
+            transferred_size: 0,
+            discard_response_body: true,
         }
     }
 
@@ -457,7 +469,7 @@ impl NetworkEventActor {
         }
         ResponseHeadersMsg {
             headers: headers_size,
-            headersSize: headers_byte_count,
+            headers_size: headers_byte_count,
         }
     }
 
@@ -467,7 +479,7 @@ impl NetworkEventActor {
         });
         RequestHeadersMsg {
             headers: self.request.headers.len(),
-            headersSize: size,
+            headers_size: size,
         }
     }
 
@@ -481,7 +493,7 @@ impl NetworkEventActor {
         }
     }
 
-    pub fn total_time(&self) -> u64 {
+    pub fn total_time(&self) -> Duration {
         self.request.connect_time + self.request.send_time
     }
 }

components/devtools/actors/object.rs

@@ -11,7 +11,7 @@ use crate::StreamId;
 
 pub struct ObjectActor {
     pub name: String,
-    pub uuid: String,
+    pub _uuid: String,
 }
 
 impl Actor for ObjectActor {
@@ -26,6 +26,7 @@ impl Actor for ObjectActor {
         _: &mut TcpStream,
         _: StreamId,
     ) -> Result<ActorMessageStatus, ()> {
+        // TODO: Handle enumSymbols for console object inspection
         Ok(ActorMessageStatus::Ignored)
     }
 }
@@ -36,7 +37,7 @@ impl ObjectActor {
             let name = registry.new_name("object");
             let actor = ObjectActor {
                 name: name.clone(),
-                uuid: uuid.clone(),
+                _uuid: uuid.clone(),
             };
 
             registry.register_script_actor(uuid, name.clone());

components/devtools/actors/performance.rs

@@ -2,6 +2,9 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
+// TODO: Is this actor still relevant?
+#![allow(dead_code)]
+
 use std::net::TcpStream;
 
 use serde::Serialize;
@@ -16,12 +19,14 @@ pub struct PerformanceActor {
 }
 
 #[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
 struct PerformanceFeatures {
-    withMarkers: bool,
-    withMemory: bool,
-    withTicks: bool,
-    withAllocations: bool,
-    withJITOptimizations: bool,
+    with_markers: bool,
+    with_memory: bool,
+    with_ticks: bool,
+    with_allocations: bool,
+    #[serde(rename = "withJITOptimizations")]
+    with_jitoptimizations: bool,
 }
 
 #[derive(Serialize)]
@@ -69,11 +74,11 @@ impl Actor for PerformanceActor {
                     from: self.name(),
                     traits: PerformanceTraits {
                         features: PerformanceFeatures {
-                            withMarkers: true,
-                            withMemory: true,
-                            withTicks: true,
-                            withAllocations: true,
-                            withJITOptimizations: true,
+                            with_markers: true,
+                            with_memory: true,
+                            with_ticks: true,
+                            with_allocations: true,
+                            with_jitoptimizations: true,
                         },
                     },
                 };
@@ -104,7 +109,7 @@ impl PerformanceActor {
     pub fn description() -> ActorDescription {
         ActorDescription {
             category: "actor",
-            typeName: "performance",
+            type_name: "performance",
             methods: vec![Method {
                 name: "canCurrentlyRecord",
                 request: Value::Object(

components/devtools/actors/preference.rs

@@ -5,6 +5,7 @@
 use std::collections::HashMap;
 use std::net::TcpStream;
 
+use log::warn;
 use serde::Serialize;
 use serde_json::{Map, Value};
 use servo_config::pref_util::PrefValue;
@@ -37,7 +38,10 @@ impl Actor for PreferenceActor {
         stream: &mut TcpStream,
         _id: StreamId,
     ) -> Result<ActorMessageStatus, ()> {
-        let mut key = msg.get("value").unwrap().as_str().unwrap();
+        let Some(mut key) = msg.get("value").and_then(|v| v.as_str()) else {
+            warn!("PreferenceActor: handle_message: value is not a string");
+            return Ok(ActorMessageStatus::Ignored);
+        };
 
         // Mapping to translate a Firefox preference name onto the corresponding Servo preference name
         let pref_name_mapping: HashMap<&str, &str> =

components/devtools/actors/process.rs

@@ -2,12 +2,17 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
+//! Liberally derived from the [Firefox JS implementation].
+//!
+//! [Firefox JS implementation]: https://searchfox.org/mozilla-central/source/devtools/server/actors/descriptors/process.js
+
 use std::net::TcpStream;
 
 use serde::Serialize;
 use serde_json::{Map, Value};
 
 use crate::actor::{Actor, ActorMessageStatus, ActorRegistry};
+use crate::actors::root::DescriptorTraits;
 use crate::protocol::JsonPacketStream;
 use crate::StreamId;
 
@@ -17,14 +22,18 @@ struct ListWorkersReply {
     workers: Vec<u32>, // TODO: use proper JSON structure.
 }
 
-pub struct ProcessActor {
-    name: String,
+#[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
+pub struct ProcessActorMsg {
+    actor: String,
+    id: u32,
+    is_parent: bool,
+    is_windowless_parent: bool,
+    traits: DescriptorTraits,
 }
 
-impl ProcessActor {
-    pub fn new(name: String) -> Self {
-        Self { name }
-    }
+pub struct ProcessActor {
+    name: String,
 }
 
 impl Actor for ProcessActor {
@@ -32,6 +41,9 @@ impl Actor for ProcessActor {
         self.name.clone()
     }
 
+    /// The process actor can handle the following messages:
+    ///
+    /// - `listWorkers`: Returns a list of web workers, not supported yet.
     fn handle_message(
         &self,
         _registry: &ActorRegistry,
@@ -54,3 +66,19 @@ impl Actor for ProcessActor {
         })
     }
 }
+
+impl ProcessActor {
+    pub fn new(name: String) -> Self {
+        Self { name }
+    }
+
+    pub fn encodable(&self) -> ProcessActorMsg {
+        ProcessActorMsg {
+            actor: self.name(),
+            id: 0,
+            is_parent: true,
+            is_windowless_parent: false,
+            traits: Default::default(),
+        }
+    }
+}

components/devtools/actors/profiler.rs

@@ -1,37 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
-
-use std::net::TcpStream;
-
-use serde_json::{Map, Value};
-
-use crate::actor::{Actor, ActorMessageStatus, ActorRegistry};
-use crate::StreamId;
-
-pub struct ProfilerActor {
-    name: String,
-}
-
-impl Actor for ProfilerActor {
-    fn name(&self) -> String {
-        self.name.clone()
-    }
-
-    fn handle_message(
-        &self,
-        _registry: &ActorRegistry,
-        _msg_type: &str,
-        _msg: &Map<String, Value>,
-        _stream: &mut TcpStream,
-        _id: StreamId,
-    ) -> Result<ActorMessageStatus, ()> {
-        Ok(ActorMessageStatus::Ignored)
-    }
-}
-
-impl ProfilerActor {
-    pub fn new(name: String) -> ProfilerActor {
-        ProfilerActor { name }
-    }
-}

components/devtools/actors/reflow.rs

@@ -0,0 +1,48 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+//! This actor is used for protocol purposes, it forwards the reflow events to clients.
+
+use std::net::TcpStream;
+
+use serde_json::{Map, Value};
+
+use crate::actor::{Actor, ActorMessageStatus, ActorRegistry};
+use crate::StreamId;
+
+pub struct ReflowActor {
+    name: String,
+}
+
+impl Actor for ReflowActor {
+    fn name(&self) -> String {
+        self.name.clone()
+    }
+
+    /// The reflow actor can handle the following messages:
+    ///
+    /// - `start`: Does nothing yet. This doesn't need a reply like other messages.
+    fn handle_message(
+        &self,
+        _registry: &ActorRegistry,
+        msg_type: &str,
+        _msg: &Map<String, Value>,
+        _stream: &mut TcpStream,
+        _id: StreamId,
+    ) -> Result<ActorMessageStatus, ()> {
+        Ok(match msg_type {
+            "start" => {
+                // TODO: Create an observer on "reflows" events
+                ActorMessageStatus::Processed
+            },
+            _ => ActorMessageStatus::Ignored,
+        })
+    }
+}
+
+impl ReflowActor {
+    pub fn new(name: String) -> Self {
+        Self { name }
+    }
+}

components/devtools/actors/root.rs

@@ -2,18 +2,22 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
+//! Connection point for all new remote devtools interactions, providing lists of know actors
+//! that perform more specific actions (targets, addons, browser chrome, etc.)
+//!
+//! Liberally derived from the [Firefox JS implementation].
+//!
+//! [Firefox JS implementation]: https://searchfox.org/mozilla-central/source/devtools/server/actors/root.js
+
 use std::net::TcpStream;
 
 use serde::Serialize;
 use serde_json::{Map, Value};
 
-/// Liberally derived from the [Firefox JS implementation]
-/// (http://mxr.mozilla.org/mozilla-central/source/toolkit/devtools/server/actors/root.js).
-/// Connection point for all new remote devtools interactions, providing lists of know actors
-/// that perform more specific actions (targets, addons, browser chrome, etc.)
 use crate::actor::{Actor, ActorMessageStatus, ActorRegistry};
 use crate::actors::device::DeviceActor;
 use crate::actors::performance::PerformanceActor;
+use crate::actors::process::{ProcessActor, ProcessActorMsg};
 use crate::actors::tab::{TabDescriptorActor, TabDescriptorActorMsg};
 use crate::actors::worker::{WorkerActor, WorkerMsg};
 use crate::protocol::{ActorDescription, JsonPacketStream};
@@ -50,7 +54,6 @@ struct GetRootReply {
 #[derive(Serialize)]
 struct ListTabsReply {
     from: String,
-    selected: u32,
     tabs: Vec<TabDescriptorActorMsg>,
 }
 
@@ -95,7 +98,7 @@ pub struct Types {
 #[derive(Serialize)]
 struct ListProcessesResponse {
     from: String,
-    processes: Vec<ProcessForm>,
+    processes: Vec<ProcessActorMsg>,
 }
 
 #[derive(Default, Serialize)]
@@ -105,21 +108,11 @@ pub struct DescriptorTraits {
     pub(crate) supports_reload_descriptor: bool,
 }
 
-#[derive(Serialize)]
-#[serde(rename_all = "camelCase")]
-struct ProcessForm {
-    actor: String,
-    id: u32,
-    is_parent: bool,
-    is_windowless_parent: bool,
-    traits: DescriptorTraits,
-}
-
 #[derive(Serialize)]
 #[serde(rename_all = "camelCase")]
 struct GetProcessResponse {
     from: String,
-    process_descriptor: ProcessForm,
+    process_descriptor: ProcessActorMsg,
 }
 
 pub struct RootActor {
@@ -155,30 +148,21 @@ impl Actor for RootActor {
             },
 
             "listProcesses" => {
+                let process = registry.find::<ProcessActor>(&self.process).encodable();
                 let reply = ListProcessesResponse {
                     from: self.name(),
-                    processes: vec![ProcessForm {
-                        actor: self.process.clone(),
-                        id: 0,
-                        is_parent: true,
-                        is_windowless_parent: false,
-                        traits: Default::default(),
-                    }],
+                    processes: vec![process],
                 };
                 let _ = stream.write_json_packet(&reply);
                 ActorMessageStatus::Processed
             },
 
+            // TODO: Unexpected message getTarget for process (when inspecting)
             "getProcess" => {
+                let process = registry.find::<ProcessActor>(&self.process).encodable();
                 let reply = GetProcessResponse {
                     from: self.name(),
-                    process_descriptor: ProcessForm {
-                        actor: self.process.clone(),
-                        id: 0,
-                        is_parent: true,
-                        is_windowless_parent: false,
-                        traits: Default::default(),
-                    },
+                    process_descriptor: process,
                 };
                 let _ = stream.write_json_packet(&reply);
                 ActorMessageStatus::Processed
@@ -196,11 +180,9 @@ impl Actor for RootActor {
                 ActorMessageStatus::Processed
             },
 
-            // https://firefox-source-docs.mozilla.org/devtools/backend/protocol.html#listing-browser-tabs
             "listTabs" => {
                 let actor = ListTabsReply {
                     from: "root".to_owned(),
-                    selected: 0,
                     tabs: self
                         .tabs
                         .iter()

components/devtools/actors/stylesheets.rs

@@ -12,9 +12,10 @@ use crate::protocol::JsonPacketStream;
 use crate::StreamId;
 
 #[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
 struct GetStyleSheetsReply {
     from: String,
-    styleSheets: Vec<u32>, // TODO: real JSON structure.
+    style_sheets: Vec<u32>, // TODO: real JSON structure.
 }
 
 pub struct StyleSheetsActor {
@@ -37,7 +38,7 @@ impl Actor for StyleSheetsActor {
             "getStyleSheets" => {
                 let msg = GetStyleSheetsReply {
                     from: self.name(),
-                    styleSheets: vec![],
+                    style_sheets: vec![],
                 };
                 let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed

components/devtools/actors/tab.rs

@@ -2,6 +2,13 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
+//! Descriptor actor that represents a web view. It can link a tab to the corresponding watcher
+//! actor to enable inspection.
+//!
+//! Liberally derived from the [Firefox JS implementation].
+//!
+//! [Firefox JS implementation]: https://searchfox.org/mozilla-central/source/devtools/server/actors/descriptors/tab.js
+
 use std::net::TcpStream;
 
 use serde::Serialize;
@@ -10,17 +17,19 @@ use serde_json::{Map, Value};
 use crate::actor::{Actor, ActorMessageStatus, ActorRegistry};
 use crate::actors::browsing_context::{BrowsingContextActor, BrowsingContextActorMsg};
 use crate::actors::root::{DescriptorTraits, RootActor};
+use crate::actors::watcher::{WatcherActor, WatcherActorMsg};
 use crate::protocol::JsonPacketStream;
 use crate::StreamId;
 
-// https://searchfox.org/mozilla-central/source/devtools/server/actors/descriptors/tab.js
 #[derive(Serialize)]
 #[serde(rename_all = "camelCase")]
 pub struct TabDescriptorActorMsg {
     actor: String,
     browser_id: u32,
+    #[serde(rename = "browsingContextID")]
     browsing_context_id: u32,
     is_zombie_tab: bool,
+    #[serde(rename = "outerWindowID")]
     outer_window_id: u32,
     selected: bool,
     title: String,
@@ -46,6 +55,13 @@ struct GetFaviconReply {
     favicon: String,
 }
 
+#[derive(Serialize)]
+struct GetWatcherReply {
+    from: String,
+    #[serde(flatten)]
+    watcher: WatcherActorMsg,
+}
+
 pub struct TabDescriptorActor {
     name: String,
     browsing_context_actor: String,
@@ -56,6 +72,14 @@ impl Actor for TabDescriptorActor {
         self.name.clone()
     }
 
+    /// The tab actor can handle the following messages:
+    ///
+    /// - `getTarget`: Returns the surrounding `BrowsingContextActor`.
+    ///
+    /// - `getFavicon`: Should return the tab favicon, but it is not yet supported.
+    ///
+    /// - `getWatcher`: Returns a `WatcherActor` linked to the tab's `BrowsingContext`. It is used
+    ///   to describe the debugging capabilities of this tab.
     fn handle_message(
         &self,
         registry: &ActorRegistry,
@@ -83,7 +107,15 @@ impl Actor for TabDescriptorActor {
                 });
                 ActorMessageStatus::Processed
             },
-            // TODO: Unexpected message getWatcher when inspecting tab (create watcher actor)
+            "getWatcher" => {
+                let ctx_actor = registry.find::<BrowsingContextActor>(&self.browsing_context_actor);
+                let watcher = registry.find::<WatcherActor>(&ctx_actor.watcher);
+                let _ = stream.write_json_packet(&GetWatcherReply {
+                    from: self.name(),
+                    watcher: watcher.encodable(),
+                });
+                ActorMessageStatus::Processed
+            },
             _ => ActorMessageStatus::Ignored,
         })
     }
@@ -94,7 +126,7 @@ impl TabDescriptorActor {
         actors: &mut ActorRegistry,
         browsing_context_actor: String,
     ) -> TabDescriptorActor {
-        let name = actors.new_name("tabDescription");
+        let name = actors.new_name("tab-description");
         let root = actors.find_mut::<RootActor>("root");
         root.tabs.push(name.clone());
         TabDescriptorActor {
@@ -105,21 +137,22 @@ impl TabDescriptorActor {
 
     pub fn encodable(&self, registry: &ActorRegistry, selected: bool) -> TabDescriptorActorMsg {
         let ctx_actor = registry.find::<BrowsingContextActor>(&self.browsing_context_actor);
-
+        let browser_id = ctx_actor.active_pipeline.get().index.0.get();
+        let browsing_context_id = ctx_actor.browsing_context_id.index.0.get();
         let title = ctx_actor.title.borrow().clone();
         let url = ctx_actor.url.borrow().clone();
 
         TabDescriptorActorMsg {
             actor: self.name(),
-            browsing_context_id: ctx_actor.browsing_context_id.index.0.get(),
-            browser_id: ctx_actor.active_pipeline.get().index.0.get(),
+            browsing_context_id,
+            browser_id,
             is_zombie_tab: false,
-            outer_window_id: ctx_actor.active_pipeline.get().index.0.get(),
+            outer_window_id: browser_id,
             selected,
             title,
             traits: DescriptorTraits {
                 watcher: true,
-                supports_reload_descriptor: false,
+                supports_reload_descriptor: true,
             },
             url,
         }

components/devtools/actors/thread.rs

@@ -9,9 +9,10 @@ use serde_json::{Map, Value};
 
 use crate::actor::{Actor, ActorMessageStatus, ActorRegistry};
 use crate::protocol::JsonPacketStream;
-use crate::StreamId;
+use crate::{EmptyReplyMsg, StreamId};
 
 #[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
 struct ThreadAttached {
     from: String,
     #[serde(rename = "type")]
@@ -19,9 +20,9 @@ struct ThreadAttached {
     actor: String,
     frame: u32,
     error: u32,
-    recordingEndpoint: u32,
-    executionPoint: u32,
-    poppedFrames: Vec<PoppedFrameMsg>,
+    recording_endpoint: u32,
+    execution_point: u32,
+    popped_frames: Vec<PoppedFrameMsg>,
     why: WhyMsg,
 }
 
@@ -48,11 +49,6 @@ struct ThreadInterruptedReply {
     type_: String,
 }
 
-#[derive(Serialize)]
-struct ReconfigureReply {
-    from: String,
-}
-
 #[derive(Serialize)]
 struct SourcesReply {
     from: String,
@@ -62,11 +58,6 @@ struct SourcesReply {
 #[derive(Serialize)]
 enum Source {}
 
-#[derive(Serialize)]
-struct VoidAttachedReply {
-    from: String,
-}
-
 pub struct ThreadActor {
     name: String,
 }
@@ -98,15 +89,15 @@ impl Actor for ThreadActor {
                     actor: registry.new_name("pause"),
                     frame: 0,
                     error: 0,
-                    recordingEndpoint: 0,
-                    executionPoint: 0,
-                    poppedFrames: vec![],
+                    recording_endpoint: 0,
+                    execution_point: 0,
+                    popped_frames: vec![],
                     why: WhyMsg {
                         type_: "attached".to_owned(),
                     },
                 };
                 let _ = stream.write_json_packet(&msg);
-                let _ = stream.write_json_packet(&VoidAttachedReply { from: self.name() });
+                let _ = stream.write_json_packet(&EmptyReplyMsg { from: self.name() });
                 ActorMessageStatus::Processed
             },
 
@@ -116,7 +107,7 @@ impl Actor for ThreadActor {
                     type_: "resumed".to_owned(),
                 };
                 let _ = stream.write_json_packet(&msg);
-                let _ = stream.write_json_packet(&VoidAttachedReply { from: self.name() });
+                let _ = stream.write_json_packet(&EmptyReplyMsg { from: self.name() });
                 ActorMessageStatus::Processed
             },
 
@@ -130,14 +121,14 @@ impl Actor for ThreadActor {
             },
 
             "reconfigure" => {
-                let _ = stream.write_json_packet(&ReconfigureReply { from: self.name() });
+                let _ = stream.write_json_packet(&EmptyReplyMsg { from: self.name() });
                 ActorMessageStatus::Processed
             },
 
             "sources" => {
                 let msg = SourcesReply {
                     from: self.name(),
-                    sources: vec![],
+                    sources: vec![], // TODO: Add sources for the debugger here
                 };
                 let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed

components/devtools/actors/timeline.rs

@@ -2,6 +2,9 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
+// TODO: Is this actor still relevant?
+#![allow(dead_code)]
+
 use std::cell::RefCell;
 use std::error::Error;
 use std::net::TcpStream;
@@ -63,21 +66,23 @@ struct StopReply {
 }
 
 #[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
 struct TimelineMarkerReply {
     name: String,
     start: HighResolutionStamp,
     end: HighResolutionStamp,
     stack: Option<Vec<()>>,
-    endStack: Option<Vec<()>>,
+    end_stack: Option<Vec<()>>,
 }
 
 #[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
 struct MarkersEmitterReply {
     #[serde(rename = "type")]
     type_: String,
     markers: Vec<TimelineMarkerReply>,
     from: String,
-    endTime: HighResolutionStamp,
+    end_time: HighResolutionStamp,
 }
 
 #[derive(Serialize)]
@@ -312,7 +317,7 @@ impl Emitter {
             start: HighResolutionStamp::new(self.start_stamp, payload.start_time),
             end: HighResolutionStamp::new(self.start_stamp, payload.end_time),
             stack: payload.start_stack,
-            endStack: payload.end_stack,
+            end_stack: payload.end_stack,
         }
     }
 
@@ -322,7 +327,7 @@ impl Emitter {
             type_: "markers".to_owned(),
             markers,
             from: self.from.clone(),
-            endTime: HighResolutionStamp::new(self.start_stamp, end_time),
+            end_time: HighResolutionStamp::new(self.start_stamp, end_time),
         };
         self.stream.write_json_packet(&reply)?;
 
@@ -330,25 +335,25 @@ impl Emitter {
             let mut lock = self.registry.lock();
             let registry = lock.as_mut().unwrap();
             let framerate_actor = registry.find_mut::<FramerateActor>(actor_name);
-            let framerateReply = FramerateEmitterReply {
+            let framerate_reply = FramerateEmitterReply {
                 type_: "framerate".to_owned(),
                 from: framerate_actor.name(),
                 delta: HighResolutionStamp::new(self.start_stamp, end_time),
                 timestamps: framerate_actor.take_pending_ticks(),
             };
-            self.stream.write_json_packet(&framerateReply)?;
+            self.stream.write_json_packet(&framerate_reply)?;
         }
 
         if let Some(ref actor_name) = self.memory_actor {
             let registry = self.registry.lock().unwrap();
             let memory_actor = registry.find::<MemoryActor>(actor_name);
-            let memoryReply = MemoryEmitterReply {
+            let memory_reply = MemoryEmitterReply {
                 type_: "memory".to_owned(),
                 from: memory_actor.name(),
                 delta: HighResolutionStamp::new(self.start_stamp, end_time),
                 measurement: memory_actor.measure(),
             };
-            self.stream.write_json_packet(&memoryReply)?;
+            self.stream.write_json_packet(&memory_reply)?;
         }
 
         Ok(())

components/devtools/actors/watcher.rs

@@ -0,0 +1,311 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+//! The watcher is the main entry point when debugging an element. Right now only web views are supported.
+//! It talks to the devtools remote and lists the capabilities of the inspected target, and it serves
+//! as a bridge for messages between actors.
+//!
+//! Liberally derived from the [Firefox JS implementation].
+//!
+//! [Firefox JS implementation]: https://searchfox.org/mozilla-central/source/devtools/server/actors/descriptors/watcher.js
+
+use std::collections::HashMap;
+use std::net::TcpStream;
+
+use log::warn;
+use serde::Serialize;
+use serde_json::{Map, Value};
+
+use self::network_parent::{NetworkParentActor, NetworkParentActorMsg};
+use crate::actor::{Actor, ActorMessageStatus, ActorRegistry};
+use crate::actors::browsing_context::{BrowsingContextActor, BrowsingContextActorMsg};
+use crate::actors::watcher::target_configuration::{
+    TargetConfigurationActor, TargetConfigurationActorMsg,
+};
+use crate::actors::watcher::thread_configuration::{
+    ThreadConfigurationActor, ThreadConfigurationActorMsg,
+};
+use crate::protocol::JsonPacketStream;
+use crate::{EmptyReplyMsg, StreamId};
+
+pub mod network_parent;
+pub mod target_configuration;
+pub mod thread_configuration;
+
+/// Describes the debugged context. It informs the server of which objects can be debugged.
+/// <https://searchfox.org/mozilla-central/source/devtools/server/actors/watcher/session-context.js>
+#[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
+pub struct SessionContext {
+    is_server_target_switching_enabled: bool,
+    supported_targets: HashMap<&'static str, bool>,
+    supported_resources: HashMap<&'static str, bool>,
+    context_type: SessionContextType,
+}
+
+impl SessionContext {
+    pub fn new(context_type: SessionContextType) -> Self {
+        Self {
+            is_server_target_switching_enabled: false,
+            // Right now we only support debugging web views (frames)
+            supported_targets: HashMap::from([
+                ("frame", true),
+                ("process", false),
+                ("worker", false),
+                ("service_worker", false),
+                ("shared_worker", false),
+            ]),
+            // At the moment we are blocking most resources to avoid errors
+            // Support for them will be enabled gradually once the corresponding actors start
+            // working propperly
+            supported_resources: HashMap::from([
+                ("console-message", true),
+                ("css-change", true),
+                ("css-message", false),
+                ("css-registered-properties", false),
+                ("document-event", false),
+                ("Cache", false),
+                ("cookies", false),
+                ("error-message", true),
+                ("extension-storage", false),
+                ("indexed-db", false),
+                ("local-storage", false),
+                ("session-storage", false),
+                ("platform-message", false),
+                ("network-event", false),
+                ("network-event-stacktrace", false),
+                ("reflow", false),
+                ("stylesheet", false),
+                ("source", false),
+                ("thread-state", false),
+                ("server-sent-event", false),
+                ("websocket", false),
+                ("jstracer-trace", false),
+                ("jstracer-state", false),
+                ("last-private-context-exit", false),
+            ]),
+            context_type,
+        }
+    }
+}
+
+#[derive(Serialize)]
+pub enum SessionContextType {
+    BrowserElement,
+    _ContextProcess,
+    _WebExtension,
+    _Worker,
+    _All,
+}
+
+#[derive(Serialize)]
+struct WatchTargetsReply {
+    from: String,
+    #[serde(rename = "type")]
+    type_: String,
+    target: BrowsingContextActorMsg,
+}
+
+#[derive(Serialize)]
+struct GetParentBrowsingContextIDReply {
+    from: String,
+    #[serde(rename = "browsingContextID")]
+    browsing_context_id: u32,
+}
+
+#[derive(Serialize)]
+struct GetNetworkParentActorReply {
+    from: String,
+    network: NetworkParentActorMsg,
+}
+
+#[derive(Serialize)]
+struct GetTargetConfigurationActorReply {
+    from: String,
+    configuration: TargetConfigurationActorMsg,
+}
+
+#[derive(Serialize)]
+struct GetThreadConfigurationActorReply {
+    from: String,
+    configuration: ThreadConfigurationActorMsg,
+}
+
+#[derive(Serialize)]
+struct WatcherTraits {
+    resources: HashMap<&'static str, bool>,
+    #[serde(flatten)]
+    targets: HashMap<&'static str, bool>,
+}
+
+#[derive(Serialize)]
+pub struct WatcherActorMsg {
+    actor: String,
+    traits: WatcherTraits,
+}
+
+pub struct WatcherActor {
+    name: String,
+    browsing_context_actor: String,
+    network_parent: String,
+    target_configuration: String,
+    thread_configuration: String,
+    session_context: SessionContext,
+}
+
+impl Actor for WatcherActor {
+    fn name(&self) -> String {
+        self.name.clone()
+    }
+
+    /// The watcher actor can handle the following messages:
+    ///
+    /// - `watchTargets`: Returns a list of objects to debug. Since we only support web views, it
+    ///   returns the associated `BrowsingContextActor`. Every target sent creates a
+    ///   `target-available-form` event.
+    ///
+    /// - `watchResources`: Start watching certain resource types. This sends
+    ///   `resource-available-form` events.
+    ///
+    /// - `getNetworkParentActor`: Returns the network parent actor. It doesn't seem to do much at
+    ///   the moment.
+    ///
+    /// - `getTargetConfigurationActor`: Returns the configuration actor for a specific target, so
+    ///   that the server can update its settings.
+    ///
+    /// - `getThreadConfigurationActor`: The same but with the configuration actor for the thread
+    fn handle_message(
+        &self,
+        registry: &ActorRegistry,
+        msg_type: &str,
+        msg: &Map<String, Value>,
+        stream: &mut TcpStream,
+        _id: StreamId,
+    ) -> Result<ActorMessageStatus, ()> {
+        let target = registry.find::<BrowsingContextActor>(&self.browsing_context_actor);
+        Ok(match msg_type {
+            "watchTargets" => {
+                let msg = WatchTargetsReply {
+                    from: self.name(),
+                    type_: "target-available-form".into(),
+                    target: target.encodable(),
+                };
+                let _ = stream.write_json_packet(&msg);
+
+                target.frame_update(stream);
+
+                // Messages that contain a `type` field are used to send event callbacks, but they
+                // don't count as a reply. Since every message needs to be responded, we send an
+                // extra empty packet to the devtools host to inform that we successfully received
+                // and processed the message so that it can continue
+                let msg = EmptyReplyMsg { from: self.name() };
+                let _ = stream.write_json_packet(&msg);
+                ActorMessageStatus::Processed
+            },
+            "watchResources" => {
+                let Some(resource_types) = msg.get("resourceTypes") else {
+                    return Ok(ActorMessageStatus::Ignored);
+                };
+                let Some(resource_types) = resource_types.as_array() else {
+                    return Ok(ActorMessageStatus::Ignored);
+                };
+
+                for resource in resource_types {
+                    let Some(resource) = resource.as_str() else {
+                        continue;
+                    };
+                    match resource {
+                        "document-event" => {
+                            target.document_event(stream);
+                        },
+                        "console-message" | "error-message" => {},
+                        _ => warn!("resource {} not handled yet", resource),
+                    }
+
+                    let msg = EmptyReplyMsg { from: self.name() };
+                    let _ = stream.write_json_packet(&msg);
+                }
+                ActorMessageStatus::Processed
+            },
+            "getParentBrowsingContextID" => {
+                let browsing_context_id = target.browsing_context_id.index.0.get();
+                let msg = GetParentBrowsingContextIDReply {
+                    from: self.name(),
+                    browsing_context_id,
+                };
+                let _ = stream.write_json_packet(&msg);
+                ActorMessageStatus::Processed
+            },
+            "getNetworkParentActor" => {
+                let network_parent = registry.find::<NetworkParentActor>(&self.network_parent);
+                let msg = GetNetworkParentActorReply {
+                    from: self.name(),
+                    network: network_parent.encodable(),
+                };
+                let _ = stream.write_json_packet(&msg);
+                ActorMessageStatus::Processed
+            },
+            "getTargetConfigurationActor" => {
+                let target_configuration =
+                    registry.find::<TargetConfigurationActor>(&self.target_configuration);
+                let msg = GetTargetConfigurationActorReply {
+                    from: self.name(),
+                    configuration: target_configuration.encodable(),
+                };
+                let _ = stream.write_json_packet(&msg);
+                ActorMessageStatus::Processed
+            },
+            "getThreadConfigurationActor" => {
+                let thread_configuration =
+                    registry.find::<ThreadConfigurationActor>(&self.thread_configuration);
+                let msg = GetThreadConfigurationActorReply {
+                    from: self.name(),
+                    configuration: thread_configuration.encodable(),
+                };
+                let _ = stream.write_json_packet(&msg);
+                ActorMessageStatus::Processed
+            },
+            _ => ActorMessageStatus::Ignored,
+        })
+    }
+}
+
+impl WatcherActor {
+    pub fn new(
+        actors: &mut ActorRegistry,
+        browsing_context_actor: String,
+        session_context: SessionContext,
+    ) -> Self {
+        let network_parent = NetworkParentActor::new(actors.new_name("network-parent"));
+        let target_configuration =
+            TargetConfigurationActor::new(actors.new_name("target-configuration"));
+        let thread_configuration =
+            ThreadConfigurationActor::new(actors.new_name("thread-configuration"));
+
+        let watcher = Self {
+            name: actors.new_name("watcher"),
+            browsing_context_actor,
+            network_parent: network_parent.name(),
+            target_configuration: target_configuration.name(),
+            thread_configuration: thread_configuration.name(),
+            session_context,
+        };
+
+        actors.register(Box::new(network_parent));
+        actors.register(Box::new(target_configuration));
+        actors.register(Box::new(thread_configuration));
+
+        watcher
+    }
+
+    pub fn encodable(&self) -> WatcherActorMsg {
+        WatcherActorMsg {
+            actor: self.name(),
+            traits: WatcherTraits {
+                resources: self.session_context.supported_resources.clone(),
+                targets: self.session_context.supported_targets.clone(),
+            },
+        }
+    }
+}

components/devtools/actors/watcher/network_parent.rs

@@ -0,0 +1,58 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+use std::net::TcpStream;
+
+use serde::Serialize;
+use serde_json::{Map, Value};
+
+use crate::actor::{Actor, ActorMessageStatus, ActorRegistry};
+use crate::protocol::JsonPacketStream;
+use crate::{EmptyReplyMsg, StreamId};
+
+#[derive(Serialize)]
+pub struct NetworkParentActorMsg {
+    actor: String,
+}
+
+pub struct NetworkParentActor {
+    name: String,
+}
+
+impl Actor for NetworkParentActor {
+    fn name(&self) -> String {
+        self.name.clone()
+    }
+
+    /// The network parent actor can handle the following messages:
+    ///
+    /// - `setSaveRequestAndResponseBodies`: Doesn't do anything yet
+    fn handle_message(
+        &self,
+        _registry: &ActorRegistry,
+        msg_type: &str,
+        _msg: &Map<String, Value>,
+        stream: &mut TcpStream,
+        _id: StreamId,
+    ) -> Result<ActorMessageStatus, ()> {
+        Ok(match msg_type {
+            "setSaveRequestAndResponseBodies" => {
+                let msg = EmptyReplyMsg { from: self.name() };
+                let _ = stream.write_json_packet(&msg);
+                ActorMessageStatus::Processed
+            },
+            _ => ActorMessageStatus::Ignored,
+        })
+    }
+}
+
+impl NetworkParentActor {
+    pub fn new(name: String) -> Self {
+        Self { name }
+    }
+
+    pub fn encodable(&self) -> NetworkParentActorMsg {
+        NetworkParentActorMsg { actor: self.name() }
+    }
+}

components/devtools/actors/watcher/target_configuration.rs

@@ -0,0 +1,101 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+//! Liberally derived from <https://searchfox.org/mozilla-central/source/devtools/server/actors/target-configuration.js>
+//! This actor manages the configuration flags that the devtools host can apply to the targets.
+
+use std::collections::HashMap;
+use std::net::TcpStream;
+
+use serde::Serialize;
+use serde_json::{Map, Value};
+
+use crate::actor::{Actor, ActorMessageStatus, ActorRegistry};
+use crate::protocol::JsonPacketStream;
+use crate::{EmptyReplyMsg, StreamId};
+
+#[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
+pub struct TargetConfigurationTraits {
+    supported_options: HashMap<&'static str, bool>,
+}
+
+#[derive(Serialize)]
+pub struct TargetConfigurationActorMsg {
+    actor: String,
+    configuration: HashMap<&'static str, bool>,
+    traits: TargetConfigurationTraits,
+}
+
+pub struct TargetConfigurationActor {
+    name: String,
+    configuration: HashMap<&'static str, bool>,
+    supported_options: HashMap<&'static str, bool>,
+}
+
+impl Actor for TargetConfigurationActor {
+    fn name(&self) -> String {
+        self.name.clone()
+    }
+
+    /// The target configuration actor can handle the following messages:
+    ///
+    /// - `updateConfiguration`: Receives new configuration flags from the devtools host.
+    fn handle_message(
+        &self,
+        _registry: &ActorRegistry,
+        msg_type: &str,
+        _msg: &Map<String, Value>,
+        stream: &mut TcpStream,
+        _id: StreamId,
+    ) -> Result<ActorMessageStatus, ()> {
+        Ok(match msg_type {
+            "updateConfiguration" => {
+                // TODO: Actually update configuration
+                let msg = EmptyReplyMsg { from: self.name() };
+                let _ = stream.write_json_packet(&msg);
+                ActorMessageStatus::Processed
+            },
+            _ => ActorMessageStatus::Ignored,
+        })
+    }
+}
+
+impl TargetConfigurationActor {
+    pub fn new(name: String) -> Self {
+        Self {
+            name,
+            configuration: HashMap::new(),
+            supported_options: HashMap::from([
+                ("cacheDisabled", false),
+                ("colorSchemeSimulation", false),
+                ("customFormatters", false),
+                ("customUserAgent", false),
+                ("javascriptEnabled", false),
+                ("overrideDPPX", false),
+                ("printSimulationEnabled", false),
+                ("rdmPaneMaxTouchPoints", false),
+                ("rdmPaneOrientation", false),
+                ("recordAllocations", false),
+                ("reloadOnTouchSimulationToggle", false),
+                ("restoreFocus", false),
+                ("serviceWorkersTestingEnabled", false),
+                ("setTabOffline", false),
+                ("touchEventsOverride", false),
+                ("tracerOptions", false),
+                ("useSimpleHighlightersForReducedMotion", false),
+            ]),
+        }
+    }
+
+    pub fn encodable(&self) -> TargetConfigurationActorMsg {
+        TargetConfigurationActorMsg {
+            actor: self.name(),
+            configuration: self.configuration.clone(),
+            traits: TargetConfigurationTraits {
+                supported_options: self.supported_options.clone(),
+            },
+        }
+    }
+}

components/devtools/actors/watcher/thread_configuration.rs

@@ -0,0 +1,67 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+//! Liberally derived from <https://searchfox.org/mozilla-central/source/devtools/server/actors/thread-configuration.js>
+//! This actor manages the configuration flags that the devtools host can apply to threads.
+
+use std::collections::HashMap;
+use std::net::TcpStream;
+
+use serde::Serialize;
+use serde_json::{Map, Value};
+
+use crate::actor::{Actor, ActorMessageStatus, ActorRegistry};
+use crate::protocol::JsonPacketStream;
+use crate::{EmptyReplyMsg, StreamId};
+
+#[derive(Serialize)]
+pub struct ThreadConfigurationActorMsg {
+    actor: String,
+}
+
+pub struct ThreadConfigurationActor {
+    name: String,
+    _configuration: HashMap<&'static str, bool>,
+}
+
+impl Actor for ThreadConfigurationActor {
+    fn name(&self) -> String {
+        self.name.clone()
+    }
+
+    /// The thread configuration actor can handle the following messages:
+    ///
+    /// - `updateConfiguration`: Receives new configuration flags from the devtools host.
+    fn handle_message(
+        &self,
+        _registry: &ActorRegistry,
+        msg_type: &str,
+        _msg: &Map<String, Value>,
+        stream: &mut TcpStream,
+        _id: StreamId,
+    ) -> Result<ActorMessageStatus, ()> {
+        Ok(match msg_type {
+            "updateConfiguration" => {
+                // TODO: Actually update configuration
+                let msg = EmptyReplyMsg { from: self.name() };
+                let _ = stream.write_json_packet(&msg);
+                ActorMessageStatus::Processed
+            },
+            _ => ActorMessageStatus::Ignored,
+        })
+    }
+}
+
+impl ThreadConfigurationActor {
+    pub fn new(name: String) -> Self {
+        Self {
+            name,
+            _configuration: HashMap::new(),
+        }
+    }
+
+    pub fn encodable(&self) -> ThreadConfigurationActorMsg {
+        ThreadConfigurationActorMsg { actor: self.name() }
+    }
+}

components/devtools/actors/worker.rs

@@ -41,12 +41,12 @@ impl WorkerActor {
     pub(crate) fn encodable(&self) -> WorkerMsg {
         WorkerMsg {
             actor: self.name.clone(),
-            consoleActor: self.console.clone(),
-            threadActor: self.thread.clone(),
+            console_actor: self.console.clone(),
+            thread_actor: self.thread.clone(),
             id: self.id.0.to_string(),
             url: self.url.to_string(),
             traits: WorkerTraits {
-                isParentInterceptEnabled: false,
+                is_parent_intercept_enabled: false,
             },
             type_: self.type_ as u32,
         }
@@ -89,8 +89,8 @@ impl Actor for WorkerActor {
                 let msg = ConnectReply {
                     from: self.name(),
                     type_: "connected".to_owned(),
-                    threadActor: self.thread.clone(),
-                    consoleActor: self.console.clone(),
+                    thread_actor: self.thread.clone(),
+                    console_actor: self.console.clone(),
                 };
                 let _ = stream.write_json_packet(&msg);
                 ActorMessageStatus::Processed
@@ -136,24 +136,27 @@ struct AttachedReply {
 }
 
 #[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
 struct ConnectReply {
     from: String,
     #[serde(rename = "type")]
     type_: String,
-    threadActor: String,
-    consoleActor: String,
+    thread_actor: String,
+    console_actor: String,
 }
 
 #[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
 struct WorkerTraits {
-    isParentInterceptEnabled: bool,
+    is_parent_intercept_enabled: bool,
 }
 
 #[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
 pub(crate) struct WorkerMsg {
     actor: String,
-    consoleActor: String,
-    threadActor: String,
+    console_actor: String,
+    thread_actor: String,
     id: String,
     url: String,
     traits: WorkerTraits,

components/devtools/lib.rs

@@ -5,11 +5,10 @@
 //! An actor-based remote devtools server implementation. Only tested with
 //! nightly Firefox versions at time of writing. Largely based on
 //! reverse-engineering of Firefox chrome devtool logs and reading of
-//! [code](http://mxr.mozilla.org/mozilla-central/source/toolkit/devtools/server/).
+//! [code](https://searchfox.org/mozilla-central/source/devtools/server).
 
 #![crate_name = "devtools"]
 #![crate_type = "rlib"]
-#![allow(non_snake_case)]
 #![deny(unsafe_code)]
 
 use std::borrow::ToOwned;
@@ -29,7 +28,7 @@ use devtools_traits::{
 };
 use embedder_traits::{EmbedderMsg, EmbedderProxy, PromptDefinition, PromptOrigin, PromptResult};
 use ipc_channel::ipc::{self, IpcSender};
-use log::{debug, warn};
+use log::{debug, trace, warn};
 use serde::Serialize;
 use servo_rand::RngCore;
 
@@ -48,12 +47,11 @@ use crate::actors::worker::{WorkerActor, WorkerType};
 use crate::protocol::JsonPacketStream;
 
 mod actor;
-/// Corresponds to <http://mxr.mozilla.org/mozilla-central/source/toolkit/devtools/server/actors/>
+/// <https://searchfox.org/mozilla-central/source/devtools/server/actors>
 mod actors {
     pub mod browsing_context;
     pub mod console;
     pub mod device;
-    pub mod emulation;
     pub mod framerate;
     pub mod inspector;
     pub mod memory;
@@ -62,12 +60,13 @@ mod actors {
     pub mod performance;
     pub mod preference;
     pub mod process;
-    pub mod profiler;
+    pub mod reflow;
     pub mod root;
     pub mod stylesheets;
     pub mod tab;
     pub mod thread;
     pub mod timeline;
+    pub mod watcher;
     pub mod worker;
 }
 mod protocol;
@@ -79,24 +78,27 @@ enum UniqueId {
 }
 
 #[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
 struct NetworkEventMsg {
     from: String,
     #[serde(rename = "type")]
     type_: String,
-    eventActor: EventActor,
+    event_actor: EventActor,
 }
 
 #[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
 struct NetworkEventUpdateMsg {
     from: String,
     #[serde(rename = "type")]
     type_: String,
-    updateType: String,
+    update_type: String,
 }
 
 #[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
 struct EventTimingsUpdateMsg {
-    totalTime: u64,
+    total_time: u64,
 }
 
 #[derive(Serialize)]
@@ -105,14 +107,20 @@ struct SecurityInfoUpdateMsg {
 }
 
 #[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
 struct ResponseStartUpdateMsg {
     from: String,
     #[serde(rename = "type")]
     type_: String,
-    updateType: String,
+    update_type: String,
     response: ResponseStartMsg,
 }
 
+#[derive(Serialize)]
+pub struct EmptyReplyMsg {
+    pub from: String,
+}
+
 /// Spin up a devtools server that listens for connections on the specified port.
 pub fn start_server(port: u16, embedder: EmbedderProxy) -> Sender<DevtoolsControlMsg> {
     let (sender, receiver) = unbounded();
@@ -181,13 +189,11 @@ fn run_server(
 
     let actors = registry.create_shareable();
 
-    let mut accepted_connections: Vec<TcpStream> = Vec::new();
-
-    let mut browsing_contexts: HashMap<BrowsingContextId, String> = HashMap::new();
-    let mut pipelines: HashMap<PipelineId, BrowsingContextId> = HashMap::new();
-    let mut actor_requests: HashMap<String, String> = HashMap::new();
-
-    let mut actor_workers: HashMap<WorkerId, String> = HashMap::new();
+    let mut accepted_connections = HashMap::new();
+    let mut browsing_contexts: HashMap<_, String> = HashMap::new();
+    let mut pipelines = HashMap::new();
+    let mut actor_requests = HashMap::new();
+    let mut actor_workers = HashMap::new();
 
     /// Process the input from a single devtools client until EOF.
     fn handle_client(actors: Arc<Mutex<ActorRegistry>>, mut stream: TcpStream, id: StreamId) {
@@ -271,6 +277,7 @@ fn run_server(
     // We need separate actor representations for each script global that exists;
     // clients can theoretically connect to multiple globals simultaneously.
     // TODO: move this into the root or target modules?
+    #[allow(clippy::too_many_arguments)]
     fn handle_new_global(
         actors: Arc<Mutex<ActorRegistry>>,
         ids: (BrowsingContextId, PipelineId, Option<WorkerId>),
@@ -279,6 +286,7 @@ fn run_server(
         pipelines: &mut HashMap<PipelineId, BrowsingContextId>,
         actor_workers: &mut HashMap<WorkerId, String>,
         page_info: DevtoolsPageInfo,
+        connections: &HashMap<StreamId, TcpStream>,
     ) {
         let mut actors = actors.lock().unwrap();
 
@@ -314,10 +322,9 @@ fn run_server(
             Root::DedicatedWorker(worker_name)
         } else {
             pipelines.insert(pipeline, browsing_context);
-            Root::BrowsingContext(
-                if let Some(actor) = browsing_contexts.get(&browsing_context) {
-                    actor.to_owned()
-                } else {
+            let name = browsing_contexts
+                .entry(browsing_context)
+                .or_insert_with(|| {
                     let browsing_context_actor = BrowsingContextActor::new(
                         console_name.clone(),
                         browsing_context,
@@ -327,11 +334,18 @@ fn run_server(
                         &mut actors,
                     );
                     let name = browsing_context_actor.name();
-                    browsing_contexts.insert(browsing_context, name.clone());
                     actors.register(Box::new(browsing_context_actor));
                     name
-                },
-            )
+                });
+
+            // Add existing streams to the new browsing context
+            let browsing_context = actors.find::<BrowsingContextActor>(name);
+            let mut streams = browsing_context.streams.borrow_mut();
+            for (id, stream) in connections {
+                streams.insert(*id, stream.try_clone().unwrap());
+            }
+
+            Root::BrowsingContext(name.clone())
         };
 
         let console = ConsoleActor {
@@ -456,7 +470,7 @@ fn run_server(
                 let msg = NetworkEventMsg {
                     from: console_actor_name,
                     type_: "networkEvent".to_owned(),
-                    eventActor: actor.event_actor(),
+                    event_actor: actor.event_actor(),
                 };
                 for stream in &mut connections {
                     let _ = stream.write_json_packet(&msg);
@@ -469,7 +483,7 @@ fn run_server(
                 let msg = NetworkEventUpdateMsg {
                     from: netevent_actor_name.clone(),
                     type_: "networkEventUpdate".to_owned(),
-                    updateType: "requestHeaders".to_owned(),
+                    update_type: "requestHeaders".to_owned(),
                 };
                 for stream in &mut connections {
                     let _ = stream.write_merged_json_packet(&msg, &actor.request_headers());
@@ -478,7 +492,7 @@ fn run_server(
                 let msg = NetworkEventUpdateMsg {
                     from: netevent_actor_name.clone(),
                     type_: "networkEventUpdate".to_owned(),
-                    updateType: "requestCookies".to_owned(),
+                    update_type: "requestCookies".to_owned(),
                 };
                 for stream in &mut connections {
                     let _ = stream.write_merged_json_packet(&msg, &actor.request_cookies());
@@ -488,7 +502,7 @@ fn run_server(
                 let msg = ResponseStartUpdateMsg {
                     from: netevent_actor_name.clone(),
                     type_: "networkEventUpdate".to_owned(),
-                    updateType: "responseStart".to_owned(),
+                    update_type: "responseStart".to_owned(),
                     response: actor.response_start(),
                 };
 
@@ -498,10 +512,10 @@ fn run_server(
                 let msg = NetworkEventUpdateMsg {
                     from: netevent_actor_name.clone(),
                     type_: "networkEventUpdate".to_owned(),
-                    updateType: "eventTimings".to_owned(),
+                    update_type: "eventTimings".to_owned(),
                 };
                 let extra = EventTimingsUpdateMsg {
-                    totalTime: actor.total_time(),
+                    total_time: actor.total_time().as_millis() as u64,
                 };
                 for stream in &mut connections {
                     let _ = stream.write_merged_json_packet(&msg, &extra);
@@ -510,7 +524,7 @@ fn run_server(
                 let msg = NetworkEventUpdateMsg {
                     from: netevent_actor_name.clone(),
                     type_: "networkEventUpdate".to_owned(),
-                    updateType: "securityInfo".to_owned(),
+                    update_type: "securityInfo".to_owned(),
                 };
                 let extra = SecurityInfoUpdateMsg {
                     state: "insecure".to_owned(),
@@ -522,7 +536,7 @@ fn run_server(
                 let msg = NetworkEventUpdateMsg {
                     from: netevent_actor_name.clone(),
                     type_: "networkEventUpdate".to_owned(),
-                    updateType: "responseContent".to_owned(),
+                    update_type: "responseContent".to_owned(),
                 };
                 for stream in &mut connections {
                     let _ = stream.write_merged_json_packet(&msg, &actor.response_content());
@@ -531,7 +545,7 @@ fn run_server(
                 let msg = NetworkEventUpdateMsg {
                     from: netevent_actor_name.clone(),
                     type_: "networkEventUpdate".to_owned(),
-                    updateType: "responseCookies".to_owned(),
+                    update_type: "responseCookies".to_owned(),
                 };
                 for stream in &mut connections {
                     let _ = stream.write_merged_json_packet(&msg, &actor.response_cookies());
@@ -540,7 +554,7 @@ fn run_server(
                 let msg = NetworkEventUpdateMsg {
                     from: netevent_actor_name,
                     type_: "networkEventUpdate".to_owned(),
-                    updateType: "responseHeaders".to_owned(),
+                    update_type: "responseHeaders".to_owned(),
                 };
                 for stream in &mut connections {
                     let _ = stream.write_merged_json_packet(&msg, &actor.response_headers());
@@ -593,13 +607,21 @@ fn run_server(
 
     let mut next_id = StreamId(0);
     while let Ok(msg) = receiver.recv() {
-        debug!("{:?}", msg);
+        trace!("{:?}", msg);
         match msg {
             DevtoolsControlMsg::FromChrome(ChromeToDevtoolsControlMsg::AddClient(stream)) => {
                 let actors = actors.clone();
                 let id = next_id;
                 next_id = StreamId(id.0 + 1);
-                accepted_connections.push(stream.try_clone().unwrap());
+                accepted_connections.insert(id, stream.try_clone().unwrap());
+
+                // Inform every browsing context of the new stream
+                for name in browsing_contexts.values() {
+                    let actors = actors.lock().unwrap();
+                    let browsing_context = actors.find::<BrowsingContextActor>(name);
+                    let mut streams = browsing_context.streams.borrow_mut();
+                    streams.insert(id, stream.try_clone().unwrap());
+                }
                 thread::Builder::new()
                     .name("DevtoolsClientHandler".to_owned())
                     .spawn(move || handle_client(actors, stream.try_clone().unwrap(), id))
@@ -631,6 +653,7 @@ fn run_server(
                 &mut pipelines,
                 &mut actor_workers,
                 pageinfo,
+                &accepted_connections,
             ),
             DevtoolsControlMsg::FromScript(ScriptToDevtoolsControlMsg::Navigate(
                 browsing_context,
@@ -667,10 +690,10 @@ fn run_server(
             )) => {
                 let console_message = ConsoleMessage {
                     message: css_error.msg,
-                    logLevel: LogLevel::Warn,
+                    log_level: LogLevel::Warn,
                     filename: css_error.filename,
-                    lineNumber: css_error.line as usize,
-                    columnNumber: css_error.column as usize,
+                    line_number: css_error.line as usize,
+                    column_number: css_error.column as usize,
                 };
                 handle_console_message(
                     actors.clone(),
@@ -688,7 +711,7 @@ fn run_server(
             )) => {
                 // copy the accepted_connections vector
                 let mut connections = Vec::<TcpStream>::new();
-                for stream in &accepted_connections {
+                for stream in accepted_connections.values() {
                     connections.push(stream.try_clone().unwrap());
                 }
 
@@ -711,7 +734,7 @@ fn run_server(
             DevtoolsControlMsg::FromChrome(ChromeToDevtoolsControlMsg::ServerExitMsg) => break,
         }
     }
-    for connection in &mut accepted_connections {
+    for connection in accepted_connections.values_mut() {
         let _ = connection.shutdown(Shutdown::Both);
     }
 }

components/devtools/protocol.rs

@@ -3,7 +3,7 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 //! Low-level wire protocol implementation. Currently only supports
-//! [JSON packets](https://wiki.mozilla.org/Remote_Debugging_Protocol_Stream_Transport#JSON_Packets).
+//! [JSON packets](https://firefox-source-docs.mozilla.org/devtools/backend/protocol.html#json-packets).
 
 use std::error::Error;
 use std::io::{Read, Write};
@@ -14,9 +14,10 @@ use serde::Serialize;
 use serde_json::{self, Value};
 
 #[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
 pub struct ActorDescription {
     pub category: &'static str,
-    pub typeName: &'static str,
+    pub type_name: &'static str,
     pub methods: Vec<Method>,
 }
 
@@ -63,7 +64,7 @@ impl JsonPacketStream for TcpStream {
     }
 
     fn read_json_packet(&mut self) -> Result<Option<Value>, String> {
-        // https://wiki.mozilla.org/Remote_Debugging_Protocol_Stream_Transport
+        // https://firefox-source-docs.mozilla.org/devtools/backend/protocol.html#stream-transport
         // In short, each JSON packet is [ascii length]:[JSON data of given length]
         let mut buffer = vec![];
         loop {

components/dom_struct/lib.rs

@@ -38,7 +38,7 @@ pub fn dom_struct(args: TokenStream, input: TokenStream) -> TokenStream {
             quote! (
                 #s2
 
-                impl crate::dom::bindings::inheritance::HasParent for #name {
+                impl crate::HasParent for #name {
                     type Parent = #ty;
                     /// This is used in a type assertion to ensure that
                     /// the source and webidls agree as to what the parent type is

components/domobject_derive/lib.rs

@@ -40,23 +40,31 @@ fn expand_dom_object(input: syn::DeriveInput) -> proc_macro2::TokenStream {
             unsafe fn to_jsval(&self,
                                 cx: *mut js::jsapi::JSContext,
                                 rval: js::rust::MutableHandleValue) {
-                let object = crate::dom::bindings::reflector::DomObject::reflector(self).get_jsobject();
+                let object = crate::DomObject::reflector(self).get_jsobject();
                 object.to_jsval(cx, rval)
             }
         }
 
-        impl #impl_generics crate::dom::bindings::reflector::DomObject for #name #ty_generics #where_clause {
+        impl #impl_generics crate::DomObject for #name #ty_generics #where_clause {
             #[inline]
-            fn reflector(&self) -> &crate::dom::bindings::reflector::Reflector {
+            fn reflector(&self) -> &crate::Reflector {
                 self.#first_field_name.reflector()
             }
         }
 
-        impl #impl_generics crate::dom::bindings::reflector::MutDomObject for #name #ty_generics #where_clause {
+        impl #impl_generics crate::MutDomObject for #name #ty_generics #where_clause {
             unsafe fn init_reflector(&self, obj: *mut js::jsapi::JSObject) {
                 self.#first_field_name.init_reflector(obj);
             }
         }
+
+        impl #impl_generics Eq for #name #ty_generics #where_clause {}
+
+        impl #impl_generics PartialEq for #name #ty_generics #where_clause {
+            fn eq(&self, other: &Self) -> bool {
+                crate::DomObject::reflector(self) == crate::DomObject::reflector(other)
+            }
+        }
     };
 
     let mut params = proc_macro2::TokenStream::new();
@@ -74,7 +82,7 @@ fn expand_dom_object(input: syn::DeriveInput) -> proc_macro2::TokenStream {
 
     let mut generics = input.generics.clone();
     generics.params.push(parse_quote!(
-        __T: crate::dom::bindings::reflector::DomObject
+        __T: crate::DomObject
     ));
 
     let (impl_generics, _, where_clause) = generics.split_for_impl();

components/fonts/Cargo.toml

@@ -9,7 +9,7 @@ publish.workspace = true
 [lib]
 name = "fonts"
 path = "lib.rs"
-test = false
+test = true
 doctest = false
 
 [dependencies]
@@ -25,7 +25,7 @@ fontsan = { git = "https://github.com/servo/fontsan" }
 fonts_traits = { workspace = true }
 harfbuzz-sys = "0.6.1"
 ipc-channel = { workspace = true }
-lazy_static = { workspace = true }
+itertools = { workspace = true }
 libc = { workspace = true }
 log = { workspace = true }
 malloc_size_of = { workspace = true }
@@ -36,6 +36,7 @@ range = { path = "../range" }
 serde = { workspace = true }
 servo_arc = { workspace = true }
 servo_atoms = { workspace = true }
+servo_config = { path = "../config" }
 servo_url = { path = "../url" }
 smallvec = { workspace = true, features = ["union"] }
 surfman = { workspace = true }
@@ -48,6 +49,9 @@ webrender_api = { workspace = true }
 webrender_traits = { workspace = true }
 xi-unicode = { workspace = true }
 
+[lints.rust]
+unexpected_cfgs = { level = "warn", check-cfg = ['cfg(ohos_mock)'] }
+
 [target.'cfg(target_os = "macos")'.dependencies]
 byteorder = { workspace = true }
 core-foundation = "0.9"
@@ -60,7 +64,7 @@ freetype-sys = { workspace = true }
 servo_allocator = { path = "../allocator" }
 
 [target.'cfg(all(target_os = "linux", not(target_env = "ohos")))'.dependencies]
-fontconfig_sys = { package = "yeslogic-fontconfig-sys", version = "5" }
+fontconfig_sys = { package = "yeslogic-fontconfig-sys", version = "6" }
 
 [target.'cfg(target_os = "android")'.dependencies]
 xml-rs = "0.8"
@@ -71,5 +75,5 @@ harfbuzz-sys = { version = "0.6.1", features = ["bundled"] }
 
 [target.'cfg(target_os = "windows")'.dependencies]
 harfbuzz-sys = { version = "0.6", features = ["bundled"] }
-dwrote = "0.11"
+dwrote = "0.11.1"
 truetype = { version = "0.47.3", features = ["ignore-invalid-language-ids"] }

components/fonts/font.rs

@@ -12,15 +12,17 @@ use std::{iter, str};
 use app_units::Au;
 use bitflags::bitflags;
 use euclid::default::{Point2D, Rect, Size2D};
+use euclid::num::Zero;
 use log::debug;
 use malloc_size_of_derive::MallocSizeOf;
 use parking_lot::RwLock;
 use serde::{Deserialize, Serialize};
-use servo_atoms::{atom, Atom};
 use smallvec::SmallVec;
 use style::computed_values::font_variant_caps;
 use style::properties::style_structs::Font as FontStyleStruct;
-use style::values::computed::font::{GenericFontFamily, SingleFontFamily};
+use style::values::computed::font::{
+    FamilyName, FontFamilyNameSyntax, GenericFontFamily, SingleFontFamily,
+};
 use style::values::computed::{FontStretch, FontStyle, FontWeight};
 use unicode_script::Script;
 use webrender_api::{FontInstanceFlags, FontInstanceKey};
@@ -48,9 +50,11 @@ pub const KERN: u32 = ot_tag!('k', 'e', 'r', 'n');
 pub const SBIX: u32 = ot_tag!('s', 'b', 'i', 'x');
 pub const CBDT: u32 = ot_tag!('C', 'B', 'D', 'T');
 pub const COLR: u32 = ot_tag!('C', 'O', 'L', 'R');
+pub const BASE: u32 = ot_tag!('B', 'A', 'S', 'E');
 
 pub const LAST_RESORT_GLYPH_ADVANCE: FractionalPixel = 10.0;
 
+/// Nanoseconds spent shaping text across all layout threads.
 static TEXT_SHAPING_PERFORMANCE_COUNTER: AtomicUsize = AtomicUsize::new(0);
 
 // PlatformFont encapsulates access to the platform's font API,
@@ -88,6 +92,7 @@ pub trait PlatformFontMethods: Sized {
     fn can_do_fast_shaping(&self) -> bool;
     fn metrics(&self) -> FontMetrics;
     fn table_for_tag(&self, _: FontTableTag) -> Option<FontTable>;
+    fn typographic_bounds(&self, _: GlyphId) -> Rect<f32>;
 
     /// Get the necessary [`FontInstanceFlags`]` for this font.
     fn webrender_font_instance_flags(&self) -> FontInstanceFlags;
@@ -134,6 +139,9 @@ pub struct FontMetrics {
     pub line_gap: Au,
     pub zero_horizontal_advance: Option<Au>,
     pub ic_horizontal_advance: Option<Au>,
+    /// The advance of the space character (' ') in this font or if there is no space,
+    /// the average char advance.
+    pub space_advance: Au,
 }
 
 impl FontMetrics {
@@ -141,20 +149,21 @@ impl FontMetrics {
     /// no font can be found.
     pub fn empty() -> Self {
         Self {
-            underline_size: Au(0),
-            underline_offset: Au(0),
-            strikeout_size: Au(0),
-            strikeout_offset: Au(0),
-            leading: Au(0),
-            x_height: Au(0),
-            em_size: Au(0),
-            ascent: Au(0),
-            descent: Au(0),
-            max_advance: Au(0),
-            average_advance: Au(0),
-            line_gap: Au(0),
+            underline_size: Au::zero(),
+            underline_offset: Au::zero(),
+            strikeout_size: Au::zero(),
+            strikeout_offset: Au::zero(),
+            leading: Au::zero(),
+            x_height: Au::zero(),
+            em_size: Au::zero(),
+            ascent: Au::zero(),
+            descent: Au::zero(),
+            max_advance: Au::zero(),
+            average_advance: Au::zero(),
+            line_gap: Au::zero(),
             zero_horizontal_advance: None,
             ic_horizontal_advance: None,
+            space_advance: Au::zero(),
         }
     }
 }
@@ -317,7 +326,6 @@ struct ShapeCacheEntry {
 
 impl Font {
     pub fn shape_text(&self, text: &str, options: &ShapingOptions) -> Arc<GlyphStore> {
-        let this = self as *const Font;
         let lookup_key = ShapeCacheEntry {
             text: text.to_owned(),
             options: *options,
@@ -329,8 +337,7 @@ impl Font {
             }
         }
 
-        let is_single_preserved_newline = text.len() == 1 && text.chars().next() == Some('\n');
-
+        let is_single_preserved_newline = text.len() == 1 && text.starts_with('\n');
         let start_time = Instant::now();
         let mut glyphs = GlyphStore::new(
             text.len(),
@@ -346,9 +353,7 @@ impl Font {
             self.shape_text_fast(text, options, &mut glyphs);
         } else {
             debug!("shape_text: Using Harfbuzz.");
-            self.shaper
-                .get_or_init(|| Shaper::new(this))
-                .shape_text(text, options, &mut glyphs);
+            self.shape_text_harfbuzz(text, options, &mut glyphs);
         }
 
         let shaped_text = Arc::new(glyphs);
@@ -364,6 +369,13 @@ impl Font {
         shaped_text
     }
 
+    fn shape_text_harfbuzz(&self, text: &str, options: &ShapingOptions, glyphs: &mut GlyphStore) {
+        let this = self as *const Font;
+        self.shaper
+            .get_or_init(|| Shaper::new(this))
+            .shape_text(text, options, glyphs);
+    }
+
     fn can_do_fast_shaping(&self, text: &str, options: &ShapingOptions) -> bool {
         options.script == Script::Latin &&
             !options.flags.contains(ShapingFlags::RTL_FLAG) &&
@@ -464,6 +476,16 @@ impl Font {
         cache.glyph_advances.insert(glyph_id, new_width);
         new_width
     }
+
+    pub fn typographic_bounds(&self, glyph_id: GlyphId) -> Rect<f32> {
+        self.handle.typographic_bounds(glyph_id)
+    }
+
+    #[allow(unsafe_code)]
+    pub fn get_baseline(&self) -> Option<FontBaseline> {
+        let this = self as *const Font;
+        unsafe { self.shaper.get_or_init(|| Shaper::new(this)).get_baseline() }
+    }
 }
 
 pub type FontRef = Arc<Font>;
@@ -480,9 +502,7 @@ pub struct FontGroup {
 }
 
 impl FontGroup {
-    pub fn new(style: &FontStyleStruct) -> FontGroup {
-        let descriptor = FontDescriptor::from(style);
-
+    pub fn new(style: &FontStyleStruct, descriptor: FontDescriptor) -> FontGroup {
         let families: SmallVec<[FontGroupFamily; 8]> = style
             .font_family
             .families
@@ -507,6 +527,14 @@ impl FontGroup {
         codepoint: char,
         next_codepoint: Option<char>,
     ) -> Option<FontRef> {
+        // Tab characters are converted into spaces when rendering.
+        // TODO: We should not render a tab character. Instead they should be converted into tab stops
+        // based upon the width of a space character in inline formatting contexts.
+        let codepoint = match codepoint {
+            '\t' => ' ',
+            _ => codepoint,
+        };
+
         let options = FallbackFontSelectionOptions::new(codepoint, next_codepoint);
 
         let should_look_for_small_caps = self.descriptor.variant == font_variant_caps::T::SmallCaps &&
@@ -630,10 +658,18 @@ impl FontGroup {
         TemplatePredicate: Fn(FontTemplateRef) -> bool,
         FontPredicate: Fn(&FontRef) -> bool,
     {
-        iter::once(FontFamilyDescriptor::serif())
-            .chain(fallback_font_families(options).into_iter().map(|family| {
-                FontFamilyDescriptor::new(FontFamilyName::from(family), FontSearchScope::Local)
-            }))
+        iter::once(FontFamilyDescriptor::default())
+            .chain(
+                fallback_font_families(options)
+                    .into_iter()
+                    .map(|family_name| {
+                        let family = SingleFontFamily::FamilyName(FamilyName {
+                            name: family_name.into(),
+                            syntax: FontFamilyNameSyntax::Quoted,
+                        });
+                        FontFamilyDescriptor::new(family, FontSearchScope::Local)
+                    }),
+            )
             .filter_map(|family_descriptor| {
                 FontGroupFamily {
                     family_descriptor,
@@ -676,11 +712,8 @@ struct FontGroupFamily {
 
 impl FontGroupFamily {
     fn new(family: &SingleFontFamily) -> FontGroupFamily {
-        let family_descriptor =
-            FontFamilyDescriptor::new(FontFamilyName::from(family), FontSearchScope::Any);
-
         FontGroupFamily {
-            family_descriptor,
+            family_descriptor: FontFamilyDescriptor::new(family.clone(), FontSearchScope::Any),
             members: None,
         }
     }
@@ -768,6 +801,7 @@ impl RunMetrics {
     }
 }
 
+/// Get the number of nanoseconds spent shaping text across all threads.
 pub fn get_and_reset_text_shaping_performance_counter() -> usize {
     TEXT_SHAPING_PERFORMANCE_COUNTER.swap(0, Ordering::SeqCst)
 }
@@ -782,73 +816,30 @@ pub enum FontSearchScope {
     Local,
 }
 
-/// A font family name used in font selection.
-#[derive(Clone, Debug, Deserialize, Eq, Hash, MallocSizeOf, PartialEq, Serialize)]
-pub enum FontFamilyName {
-    /// A specific name such as `"Arial"`
-    Specific(Atom),
-
-    /// A generic name such as `sans-serif`
-    Generic(Atom),
-}
-
-impl FontFamilyName {
-    pub fn name(&self) -> &str {
-        match *self {
-            FontFamilyName::Specific(ref name) => name,
-            FontFamilyName::Generic(ref name) => name,
-        }
-    }
-}
-
-impl<'a> From<&'a SingleFontFamily> for FontFamilyName {
-    fn from(other: &'a SingleFontFamily) -> FontFamilyName {
-        match *other {
-            SingleFontFamily::FamilyName(ref family_name) => {
-                FontFamilyName::Specific(family_name.name.clone())
-            },
-
-            SingleFontFamily::Generic(generic) => FontFamilyName::Generic(match generic {
-                GenericFontFamily::None => panic!("Shouldn't appear in style"),
-                GenericFontFamily::Serif => atom!("serif"),
-                GenericFontFamily::SansSerif => atom!("sans-serif"),
-                GenericFontFamily::Monospace => atom!("monospace"),
-                GenericFontFamily::Cursive => atom!("cursive"),
-                GenericFontFamily::Fantasy => atom!("fantasy"),
-                GenericFontFamily::SystemUi => atom!("system-ui"),
-            }),
-        }
-    }
-}
-
-impl<'a> From<&'a str> for FontFamilyName {
-    fn from(other: &'a str) -> FontFamilyName {
-        FontFamilyName::Specific(Atom::from(other))
-    }
-}
-
 /// The font family parameters for font selection.
 #[derive(Clone, Debug, Deserialize, Eq, Hash, MallocSizeOf, PartialEq, Serialize)]
 pub struct FontFamilyDescriptor {
-    pub name: FontFamilyName,
+    pub family: SingleFontFamily,
     pub scope: FontSearchScope,
 }
 
 impl FontFamilyDescriptor {
-    pub fn new(name: FontFamilyName, scope: FontSearchScope) -> FontFamilyDescriptor {
-        FontFamilyDescriptor { name, scope }
+    pub fn new(family: SingleFontFamily, scope: FontSearchScope) -> FontFamilyDescriptor {
+        FontFamilyDescriptor { family, scope }
     }
 
-    fn serif() -> FontFamilyDescriptor {
+    fn default() -> FontFamilyDescriptor {
         FontFamilyDescriptor {
-            name: FontFamilyName::Generic(atom!("serif")),
+            family: SingleFontFamily::Generic(GenericFontFamily::None),
             scope: FontSearchScope::Local,
         }
     }
+}
 
-    pub fn name(&self) -> &str {
-        self.name.name()
-    }
+pub struct FontBaseline {
+    pub ideographic_baseline: f32,
+    pub alphabetic_baseline: f32,
+    pub hanging_baseline: f32,
 }
 
 /// Given a mapping array `mapping` and a value, map that value onto
@@ -884,3 +875,87 @@ pub(crate) fn map_platform_values_to_style_values(mapping: &[(f64, f64)], value:
 
     mapping[mapping.len() - 1].1
 }
+
+#[cfg(test)]
+mod test {
+    #[cfg(target_os = "windows")]
+    #[test]
+    fn test_shape_text_fast() {
+        use std::fs::File;
+        use std::io::Read;
+        use std::path::PathBuf;
+        use std::sync::Arc;
+
+        use app_units::Au;
+        use euclid::num::Zero;
+        use servo_url::ServoUrl;
+        use style::properties::longhands::font_variant_caps::computed_value::T as FontVariantCaps;
+        use style::values::computed::{FontStretch, FontStyle, FontWeight};
+        use unicode_script::Script;
+
+        use crate::platform::font::PlatformFont;
+        use crate::{
+            Font, FontDescriptor, FontIdentifier, FontTemplate, GlyphStore, PlatformFontMethods,
+            ShapingFlags, ShapingOptions,
+        };
+
+        let path: PathBuf = [
+            env!("CARGO_MANIFEST_DIR"),
+            "tests",
+            "support",
+            "dejavu-fonts-ttf-2.37",
+            "ttf",
+            "DejaVuSans.ttf",
+        ]
+        .iter()
+        .collect();
+
+        let identifier = FontIdentifier::Web(ServoUrl::from_file_path(path.clone()).unwrap());
+        let file = File::open(path).unwrap();
+        let data: Arc<Vec<u8>> = Arc::new(file.bytes().map(|b| b.unwrap()).collect());
+        let platform_font =
+            PlatformFont::new_from_data(identifier.clone(), data.clone(), 0, None).unwrap();
+
+        let template = FontTemplate {
+            identifier,
+            descriptor: platform_font.descriptor(),
+            data: Some(data),
+            stylesheet: None,
+        };
+        let descriptor = FontDescriptor {
+            weight: FontWeight::normal(),
+            stretch: FontStretch::hundred(),
+            style: FontStyle::normal(),
+            variant: FontVariantCaps::Normal,
+            pt_size: Au::from_px(24),
+        };
+        let font = Font::new(
+            Arc::new(atomic_refcell::AtomicRefCell::new(template)),
+            descriptor,
+            None,
+        )
+        .unwrap();
+
+        let shaping_options = ShapingOptions {
+            letter_spacing: None,
+            word_spacing: Au::zero(),
+            script: Script::Latin,
+            flags: ShapingFlags::empty(),
+        };
+        let text = "WAVE";
+
+        assert!(font.can_do_fast_shaping(text, &shaping_options));
+
+        let mut expected_glyphs = GlyphStore::new(text.len(), false, false, false);
+        font.shape_text_harfbuzz(text, &shaping_options, &mut expected_glyphs);
+
+        let mut glyphs = GlyphStore::new(text.len(), false, false, false);
+        font.shape_text_fast(text, &shaping_options, &mut glyphs);
+
+        assert_eq!(glyphs.len(), expected_glyphs.len());
+        assert_eq!(
+            glyphs.total_advance().to_nearest_px(),
+            expected_glyphs.total_advance().to_nearest_px()
+        );
+    }
+}

components/fonts/font_cache_thread.rs

@@ -3,6 +3,7 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 use std::borrow::ToOwned;
+use std::cell::OnceCell;
 use std::collections::HashMap;
 use std::ops::{Deref, RangeInclusive};
 use std::sync::Arc;
@@ -14,23 +15,25 @@ use ipc_channel::ipc::{self, IpcBytesReceiver, IpcBytesSender, IpcReceiver, IpcS
 use log::debug;
 use malloc_size_of_derive::MallocSizeOf;
 use serde::{Deserialize, Serialize};
-use servo_atoms::Atom;
+use servo_config::pref;
 use servo_url::ServoUrl;
 use style::font_face::{FontFaceRuleData, FontStyle as FontFaceStyle};
-use style::values::computed::font::{FixedPoint, FontStyleFixedPoint};
+use style::values::computed::font::{
+    FixedPoint, FontStyleFixedPoint, GenericFontFamily, SingleFontFamily,
+};
 use style::values::computed::{FontStretch, FontWeight};
 use style::values::specified::FontStretch as SpecifiedFontStretch;
 use webrender_api::{FontInstanceFlags, FontInstanceKey, FontKey};
 use webrender_traits::WebRenderFontApi;
 
-use crate::font::{FontDescriptor, FontFamilyName};
+use crate::font::FontDescriptor;
 use crate::font_store::FontStore;
 use crate::font_template::{
     FontTemplate, FontTemplateDescriptor, FontTemplateRef, FontTemplateRefMethods,
 };
 use crate::platform::font_list::{
-    for_each_available_family, for_each_variation, system_default_family, LocalFontIdentifier,
-    SANS_SERIF_FONT_FAMILY,
+    default_system_generic_font_family, for_each_available_family, for_each_variation,
+    LocalFontIdentifier,
 };
 
 #[derive(Clone, Debug, Deserialize, Eq, Hash, MallocSizeOf, PartialEq, Serialize)]
@@ -60,7 +63,7 @@ pub struct SerializedFontTemplate {
 pub enum Command {
     GetFontTemplates(
         Option<FontDescriptor>,
-        FontFamilyName,
+        SingleFontFamily,
         IpcSender<Vec<SerializedFontTemplate>>,
     ),
     GetFontInstance(
@@ -75,43 +78,27 @@ pub enum Command {
     Ping,
 }
 
+#[derive(Default)]
+struct ResolvedGenericFontFamilies {
+    default: OnceCell<LowercaseFontFamilyName>,
+    serif: OnceCell<LowercaseFontFamilyName>,
+    sans_serif: OnceCell<LowercaseFontFamilyName>,
+    monospace: OnceCell<LowercaseFontFamilyName>,
+    fantasy: OnceCell<LowercaseFontFamilyName>,
+    cursive: OnceCell<LowercaseFontFamilyName>,
+    system_ui: OnceCell<LowercaseFontFamilyName>,
+}
+
 /// The font cache thread itself. It maintains a list of reference counted
 /// font templates that are currently in use.
 struct FontCache {
     port: IpcReceiver<Command>,
-    generic_fonts: HashMap<FontFamilyName, LowercaseString>,
     font_data: HashMap<FontIdentifier, Arc<Vec<u8>>>,
     local_families: FontStore,
     webrender_api: Box<dyn WebRenderFontApi>,
     webrender_fonts: HashMap<FontIdentifier, FontKey>,
     font_instances: HashMap<(FontKey, Au), FontInstanceKey>,
-}
-
-fn populate_generic_fonts() -> HashMap<FontFamilyName, LowercaseString> {
-    let mut generic_fonts = HashMap::with_capacity(5);
-
-    append_map(&mut generic_fonts, "serif", "Times New Roman");
-    append_map(&mut generic_fonts, "sans-serif", SANS_SERIF_FONT_FAMILY);
-    append_map(&mut generic_fonts, "cursive", "Apple Chancery");
-    append_map(&mut generic_fonts, "fantasy", "Papyrus");
-    append_map(&mut generic_fonts, "monospace", "Menlo");
-
-    fn append_map(
-        generic_fonts: &mut HashMap<FontFamilyName, LowercaseString>,
-        generic_name: &str,
-        mapped_name: &str,
-    ) {
-        let family_name = match system_default_family(generic_name) {
-            Some(system_default) => LowercaseString::new(&system_default),
-            None => LowercaseString::new(mapped_name),
-        };
-
-        let generic_name = FontFamilyName::Generic(Atom::from(generic_name));
-
-        generic_fonts.insert(generic_name, family_name);
-    }
-
-    generic_fonts
+    generic_fonts: ResolvedGenericFontFamilies,
 }
 
 impl FontCache {
@@ -120,9 +107,9 @@ impl FontCache {
             let msg = self.port.recv().unwrap();
 
             match msg {
-                Command::GetFontTemplates(descriptor_to_match, font_family_name, result) => {
+                Command::GetFontTemplates(descriptor_to_match, font_family, result) => {
                     let templates =
-                        self.find_font_templates(descriptor_to_match.as_ref(), &font_family_name);
+                        self.find_font_templates(descriptor_to_match.as_ref(), &font_family);
                     debug!("Found templates for descriptor {descriptor_to_match:?}: ");
                     debug!("  {templates:?}");
 
@@ -192,28 +179,21 @@ impl FontCache {
     fn refresh_local_families(&mut self) {
         self.local_families.clear();
         for_each_available_family(|family_name| {
-            let family_name = LowercaseString::new(&family_name);
-            self.local_families.families.entry(family_name).or_default();
+            self.local_families
+                .families
+                .entry(family_name.as_str().into())
+                .or_default();
         });
     }
 
-    fn transform_family(&self, family_name: &FontFamilyName) -> LowercaseString {
-        match self.generic_fonts.get(family_name) {
-            None => LowercaseString::from(family_name),
-            Some(mapped_family) => (*mapped_family).clone(),
-        }
-    }
-
     fn find_font_templates(
         &mut self,
         descriptor_to_match: Option<&FontDescriptor>,
-        family_name: &FontFamilyName,
+        family: &SingleFontFamily,
     ) -> Vec<FontTemplateRef> {
         // TODO(Issue #188): look up localized font family names if canonical name not found
         // look up canonical name
-        // TODO(Issue #192: handle generic font families, like 'serif' and 'sans-serif'.
-        // if such family exists, try to match style to a font
-        let family_name = self.transform_family(family_name);
+        let family_name = self.family_name_for_single_font_family(family);
         self.local_families
             .families
             .get_mut(&family_name)
@@ -267,13 +247,53 @@ impl FontCache {
                 webrender_font_api.add_font_instance(font_key, pt_size.to_f32_px(), flags)
             })
     }
+
+    pub(crate) fn family_name_for_single_font_family(
+        &mut self,
+        family: &SingleFontFamily,
+    ) -> LowercaseFontFamilyName {
+        let generic = match family {
+            SingleFontFamily::FamilyName(family_name) => return family_name.name.clone().into(),
+            SingleFontFamily::Generic(generic) => generic,
+        };
+
+        let resolved_font = match generic {
+            GenericFontFamily::None => &self.generic_fonts.default,
+            GenericFontFamily::Serif => &self.generic_fonts.serif,
+            GenericFontFamily::SansSerif => &self.generic_fonts.sans_serif,
+            GenericFontFamily::Monospace => &self.generic_fonts.monospace,
+            GenericFontFamily::Cursive => &self.generic_fonts.cursive,
+            GenericFontFamily::Fantasy => &self.generic_fonts.fantasy,
+            GenericFontFamily::SystemUi => &self.generic_fonts.system_ui,
+        };
+
+        resolved_font
+            .get_or_init(|| {
+                // First check whether the font is set in the preferences.
+                let family_name = match generic {
+                    GenericFontFamily::None => pref!(fonts.default),
+                    GenericFontFamily::Serif => pref!(fonts.serif),
+                    GenericFontFamily::SansSerif => pref!(fonts.sans_serif),
+                    GenericFontFamily::Monospace => pref!(fonts.monospace),
+                    _ => String::new(),
+                };
+
+                if !family_name.is_empty() {
+                    return family_name.into();
+                }
+
+                // Otherwise ask the platform for the default family for the generic font.
+                default_system_generic_font_family(*generic)
+            })
+            .clone()
+    }
 }
 
 pub trait FontSource: Clone {
     fn find_matching_font_templates(
         &self,
         descriptor_to_match: Option<&FontDescriptor>,
-        font_family_name: &FontFamilyName,
+        font_family_name: &SingleFontFamily,
     ) -> Vec<FontTemplateRef>;
     fn get_system_font_instance(
         &self,
@@ -313,7 +333,7 @@ pub enum ComputedFontStyleDescriptor {
 /// on the contents of the font itself.
 #[derive(Clone, Debug, Default, Deserialize, Serialize)]
 pub struct CSSFontFaceDescriptors {
-    pub family_name: LowercaseString,
+    pub family_name: LowercaseFontFamilyName,
     pub weight: Option<(FontWeight, FontWeight)>,
     pub stretch: Option<(FontStretch, FontStretch)>,
     pub style: Option<ComputedFontStyleDescriptor>,
@@ -323,7 +343,7 @@ pub struct CSSFontFaceDescriptors {
 impl CSSFontFaceDescriptors {
     pub fn new(family_name: &str) -> Self {
         CSSFontFaceDescriptors {
-            family_name: LowercaseString::new(family_name),
+            family_name: family_name.into(),
             ..Default::default()
         }
     }
@@ -373,7 +393,7 @@ impl From<&FontFaceRuleData> for CSSFontFaceDescriptors {
             .map(|ranges| ranges.iter().map(|range| range.start..=range.end).collect());
 
         CSSFontFaceDescriptors {
-            family_name: LowercaseString::new(&family_name),
+            family_name: family_name.into(),
             weight,
             stretch,
             style,
@@ -389,18 +409,15 @@ impl FontCacheThread {
         thread::Builder::new()
             .name("FontCache".to_owned())
             .spawn(move || {
-                // TODO: Allow users to specify these.
-                let generic_fonts = populate_generic_fonts();
-
                 #[allow(clippy::default_constructed_unit_structs)]
                 let mut cache = FontCache {
                     port,
-                    generic_fonts,
                     font_data: HashMap::new(),
                     local_families: Default::default(),
                     webrender_api,
                     webrender_fonts: HashMap::new(),
                     font_instances: HashMap::new(),
+                    generic_fonts: Default::default(),
                 };
 
                 cache.refresh_local_families();
@@ -454,13 +471,13 @@ impl FontSource for FontCacheThread {
     fn find_matching_font_templates(
         &self,
         descriptor_to_match: Option<&FontDescriptor>,
-        font_family_name: &FontFamilyName,
+        font_family: &SingleFontFamily,
     ) -> Vec<FontTemplateRef> {
         let (response_chan, response_port) = ipc::channel().expect("failed to create IPC channel");
         self.chan
             .send(Command::GetFontTemplates(
                 descriptor_to_match.cloned(),
-                font_family_name.clone(),
+                font_family.clone(),
                 response_chan,
             ))
             .expect("failed to send message to font cache thread");
@@ -521,25 +538,19 @@ impl FontSource for FontCacheThread {
 }
 
 #[derive(Clone, Debug, Default, Deserialize, Eq, Hash, PartialEq, Serialize)]
-pub struct LowercaseString {
+pub struct LowercaseFontFamilyName {
     inner: String,
 }
 
-impl LowercaseString {
-    pub fn new(s: &str) -> LowercaseString {
-        LowercaseString {
-            inner: s.to_lowercase(),
+impl<T: AsRef<str>> From<T> for LowercaseFontFamilyName {
+    fn from(value: T) -> Self {
+        LowercaseFontFamilyName {
+            inner: value.as_ref().to_lowercase(),
         }
     }
 }
 
-impl<'a> From<&'a FontFamilyName> for LowercaseString {
-    fn from(family_name: &'a FontFamilyName) -> LowercaseString {
-        LowercaseString::new(family_name.name())
-    }
-}
-
-impl Deref for LowercaseString {
+impl Deref for LowercaseFontFamilyName {
     type Target = str;
 
     #[inline]
@@ -548,7 +559,7 @@ impl Deref for LowercaseString {
     }
 }
 
-impl fmt::Display for LowercaseString {
+impl fmt::Display for LowercaseFontFamilyName {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         self.inner.fmt(f)
     }

components/fonts/font_context.rs

@@ -24,19 +24,19 @@ use style::font_face::{FontFaceSourceFormat, FontFaceSourceFormatKeyword, Source
 use style::media_queries::Device;
 use style::properties::style_structs::Font as FontStyleStruct;
 use style::shared_lock::SharedRwLockReadGuard;
-use style::stylesheets::{DocumentStyleSheet, StylesheetInDocument};
+use style::stylesheets::{CssRule, DocumentStyleSheet, FontFaceRule, StylesheetInDocument};
+use style::values::computed::font::{FamilyName, FontFamilyNameSyntax, SingleFontFamily};
 use style::Atom;
 use url::Url;
 use webrender_api::{FontInstanceKey, FontKey};
 
 use crate::font::{
-    Font, FontDescriptor, FontFamilyDescriptor, FontFamilyName, FontGroup, FontRef, FontSearchScope,
-};
-use crate::font_cache_thread::{
-    CSSFontFaceDescriptors, FontIdentifier, FontSource, LowercaseString,
+    Font, FontDescriptor, FontFamilyDescriptor, FontGroup, FontRef, FontSearchScope,
 };
+use crate::font_cache_thread::{CSSFontFaceDescriptors, FontIdentifier, FontSource};
 use crate::font_store::{CrossThreadFontStore, CrossThreadWebRenderFontStore};
 use crate::font_template::{FontTemplate, FontTemplateRef, FontTemplateRefMethods};
+use crate::LowercaseFontFamilyName;
 
 static SMALL_CAPS_SCALE_FACTOR: f32 = 0.8; // Matches FireFox (see gfxFont.h)
 
@@ -170,28 +170,39 @@ impl<S: FontSource> FontContext<S> {
         font
     }
 
+    fn matching_web_font_templates(
+        &self,
+        descriptor_to_match: &FontDescriptor,
+        family_descriptor: &FontFamilyDescriptor,
+    ) -> Option<Vec<FontTemplateRef>> {
+        if family_descriptor.scope != FontSearchScope::Any {
+            return None;
+        }
+
+        // Do not look for generic fonts in our list of web fonts.
+        let SingleFontFamily::FamilyName(ref family_name) = family_descriptor.family else {
+            return None;
+        };
+
+        self.web_fonts
+            .read()
+            .families
+            .get(&family_name.name.clone().into())
+            .map(|templates| templates.find_for_descriptor(Some(descriptor_to_match)))
+    }
+
+    /// Try to find matching templates in this [`FontContext`], first looking in the list of web fonts and
+    /// falling back to asking the [`super::FontCacheThread`] for a matching system font.
     pub fn matching_templates(
         &self,
         descriptor_to_match: &FontDescriptor,
         family_descriptor: &FontFamilyDescriptor,
     ) -> Vec<FontTemplateRef> {
-        // First try to find an appropriate web font that matches this descriptor.
-        if family_descriptor.scope == FontSearchScope::Any {
-            let family_name = LowercaseString::from(&family_descriptor.name);
-            if let Some(templates) = self
-                .web_fonts
-                .read()
-                .families
-                .get(&family_name)
-                .map(|templates| templates.find_for_descriptor(Some(descriptor_to_match)))
-            {
-                return templates;
-            }
-        }
-
-        // If not request a matching font from the system font cache.
-        self.cache
-            .matching_templates(descriptor_to_match, family_descriptor)
+        self.matching_web_font_templates(descriptor_to_match, family_descriptor)
+            .unwrap_or_else(|| {
+                self.cache
+                    .matching_templates(descriptor_to_match, family_descriptor)
+            })
     }
 
     /// Create a `Font` for use in layout calculations, from a `FontTemplateData` returned by the
@@ -275,10 +286,14 @@ impl<S: FontSource + Send + 'static> FontContextWebFontMethods for Arc<FontConte
         };
 
         let mut number_loading = 0;
-        stylesheet.effective_font_face_rules(device, guard, |rule| {
-            let font_face = match rule.font_face() {
-                Some(font_face) => font_face,
-                None => return,
+        for rule in stylesheet.effective_rules(device, guard) {
+            let CssRule::FontFace(ref lock) = *rule else {
+                continue;
+            };
+
+            let rule: &FontFaceRule = lock.read_with(guard);
+            let Some(font_face) = rule.font_face() else {
+                continue;
             };
 
             let sources: Vec<Source> = font_face
@@ -290,7 +305,7 @@ impl<S: FontSource + Send + 'static> FontContextWebFontMethods for Arc<FontConte
                 .cloned()
                 .collect();
             if sources.is_empty() {
-                return;
+                continue;
             }
 
             // Fetch all local fonts first, beacause if we try to fetch them later on during the process of
@@ -306,10 +321,13 @@ impl<S: FontSource + Send + 'static> FontContextWebFontMethods for Arc<FontConte
                     local_fonts
                         .entry(family_name.name.clone())
                         .or_insert_with(|| {
-                            let family_name = FontFamilyName::Specific(family_name.name.clone());
+                            let family = SingleFontFamily::FamilyName(FamilyName {
+                                name: family_name.name.clone(),
+                                syntax: FontFamilyNameSyntax::Quoted,
+                            });
                             self.font_source
                                 .lock()
-                                .find_matching_font_templates(None, &family_name)
+                                .find_matching_font_templates(None, &family)
                                 .first()
                                 .cloned()
                         });
@@ -334,7 +352,7 @@ impl<S: FontSource + Send + 'static> FontContextWebFontMethods for Arc<FontConte
             if let Some(ref synchronous_receiver) = synchronous_receiver {
                 synchronous_receiver.recv().unwrap();
             }
-        });
+        }
 
         number_loading
     }
@@ -449,7 +467,7 @@ impl<S: FontSource + Send + 'static> FontContextWebFontMethods for Arc<FontConte
 struct RemoteWebFontDownloader<FCT: FontSource> {
     font_context: Arc<FontContext<FCT>>,
     url: ServoArc<Url>,
-    web_font_family_name: LowercaseString,
+    web_font_family_name: LowercaseFontFamilyName,
     response_valid: Mutex<bool>,
     response_data: Mutex<Vec<u8>>,
 }
@@ -464,7 +482,7 @@ impl<FCT: FontSource + Send + 'static> RemoteWebFontDownloader<FCT> {
     fn download(
         url_source: UrlSource,
         font_context: Arc<FontContext<FCT>>,
-        web_font_family_name: LowercaseString,
+        web_font_family_name: LowercaseFontFamilyName,
         state: WebFontDownloadState,
     ) {
         // https://drafts.csswg.org/css-fonts/#font-fetching-requirements
@@ -648,7 +666,7 @@ impl<FCT: FontSource> CachingFontSource<FCT> {
         let templates = self
             .font_cache_thread
             .lock()
-            .find_matching_font_templates(Some(descriptor_to_match), &family_descriptor.name);
+            .find_matching_font_templates(Some(descriptor_to_match), &family_descriptor.family);
         self.templates.write().insert(cache_key, templates.clone());
 
         templates
@@ -663,7 +681,11 @@ impl<FCT: FontSource> CachingFontSource<FCT> {
         if let Some(font_group) = self.resolved_font_groups.read().get(&cache_key) {
             return font_group.clone();
         }
-        let font_group = Arc::new(RwLock::new(FontGroup::new(&cache_key.style)));
+
+        let mut descriptor = FontDescriptor::from(&*cache_key.style);
+        descriptor.pt_size = size;
+
+        let font_group = Arc::new(RwLock::new(FontGroup::new(&cache_key.style, descriptor)));
         self.resolved_font_groups
             .write()
             .insert(cache_key, font_group.clone());