devtools: Implement getBlackboxingActor (#44142)

Adds `BlackboxingActor` boilerplate and implements `getBlackboxingActor`

Testing: Added a geckordp test for `getBlackboxingActor`
Fixes: Part of https://github.com/servo/servo/issues/36027

Signed-off-by: Freya Arbjerg <git@arbjerg.dev>

components/devtools/actors/blackboxing.rs

@@ -0,0 +1,34 @@
+/* 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 malloc_size_of_derive::MallocSizeOf;
+
+use crate::ActorMsg;
+use crate::actor::{Actor, ActorEncode, ActorRegistry};
+
+#[derive(MallocSizeOf)]
+pub(crate) struct BlackboxingActor {
+    name: String,
+}
+
+impl Actor for BlackboxingActor {
+    fn name(&self) -> String {
+        self.name.clone()
+    }
+}
+
+impl BlackboxingActor {
+    pub fn register(registry: &ActorRegistry) -> String {
+        let name = registry.new_name::<Self>();
+        let actor = Self { name: name.clone() };
+        registry.register::<Self>(actor);
+        name
+    }
+}
+
+impl ActorEncode<ActorMsg> for BlackboxingActor {
+    fn encode(&self, _: &ActorRegistry) -> ActorMsg {
+        ActorMsg { actor: self.name() }
+    }
+}

components/devtools/actors/watcher.rs

@@ -25,6 +25,7 @@ use super::breakpoint::BreakpointListActor;
 use super::thread::ThreadActor;
 use super::worker::WorkerTargetActorMsg;
 use crate::actor::{Actor, ActorEncode, ActorError, ActorRegistry};
+use crate::actors::blackboxing::BlackboxingActor;
 use crate::actors::browsing_context::{BrowsingContextActor, BrowsingContextActorMsg};
 use crate::actors::console::ConsoleActor;
 use crate::actors::root::RootActor;
@@ -146,6 +147,13 @@ struct GetThreadConfigurationActorReply {
     configuration: ActorMsg,
 }
 
+#[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
+struct GetBlackboxingActorReply {
+    from: String,
+    blackboxing: ActorMsg,
+}
+
 #[derive(Serialize)]
 #[serde(rename_all = "camelCase")]
 struct GetBreakpointListActorReply {
@@ -187,6 +195,7 @@ pub(crate) struct WatcherActor {
     target_configuration_name: String,
     thread_configuration_name: String,
     breakpoint_list_name: String,
+    blackboxing_name: String,
     session_context: SessionContext,
 }
 
@@ -426,6 +435,13 @@ impl Actor for WatcherActor {
                 };
                 request.reply_final(&msg)?
             },
+            "getBlackboxingActor" => {
+                let msg = GetBlackboxingActorReply {
+                    from: self.name(),
+                    blackboxing: registry.encode::<BlackboxingActor, _>(&self.blackboxing_name),
+                };
+                request.reply_final(&msg)?
+            },
             _ => return Err(ActorError::UnrecognizedPacketType),
         };
         Ok(())
@@ -449,6 +465,7 @@ impl WatcherActor {
         let thread_configuration_name = ThreadConfigurationActor::register(registry);
         let breakpoint_list_name =
             BreakpointListActor::register(registry, browsing_context_name.clone());
+        let blackboxing_name = BlackboxingActor::register(registry);
 
         let name = registry.new_name::<Self>();
         let actor = Self {
@@ -458,6 +475,7 @@ impl WatcherActor {
             target_configuration_name,
             thread_configuration_name,
             breakpoint_list_name,
+            blackboxing_name,
             session_context,
         };
 

components/devtools/lib.rs

@@ -61,6 +61,7 @@ use crate::protocol::{DevtoolsConnection, JsonPacketStream};
 mod actor;
 /// <https://searchfox.org/mozilla-central/source/devtools/server/actors>
 mod actors {
+    pub mod blackboxing;
     pub mod breakpoint;
     pub mod browsing_context;
     pub mod console;

python/servo/devtools_tests.py

@@ -234,6 +234,13 @@ class DevtoolsTests(unittest.IsolatedAsyncioTestCase):
             response2 = devtools.watcher.get_breakpoint_list_actor()
             self.assertEqual(response1["breakpointList"]["actor"], response2["breakpointList"]["actor"])
 
+    def test_watcher_returns_same_blackboxing_actor_every_time(self):
+        self.run_servoshell(url="data:text/html,")
+        with Devtools.connect() as devtools:
+            response1 = devtools.watcher.get_blackboxing_actor()
+            response2 = devtools.watcher.get_blackboxing_actor()
+            self.assertEqual(response1["blackboxing"]["actor"], response2["blackboxing"]["actor"])
+
     def test_breakpoint_pause(self):
         self.run_servoshell(url=f"{self.base_urls[0]}/debugger/loop.html")
         with Devtools.connect() as devtools: