LibJS: Move tests to /Tests/LibJS

Author: https://github.com/gmta
Commit: https://github.com/LadybirdBrowser/ladybird/commit/e3faa9b5add
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/7572
Reviewed-by: https://github.com/trflynn89 ✅

Tests/LibJS/Runtime/builtins/ArrayBuffer/ArrayBuffer.js

@@ -0,0 +1,31 @@
+test("basic functionality", () => {
+    expect(ArrayBuffer).toHaveLength(1);
+    expect(ArrayBuffer.name).toBe("ArrayBuffer");
+    expect(ArrayBuffer.prototype.constructor).toBe(ArrayBuffer);
+    expect(new ArrayBuffer()).toBeInstanceOf(ArrayBuffer);
+    expect(typeof new ArrayBuffer()).toBe("object");
+});
+
+test("ArrayBuffer constructor must be invoked with 'new'", () => {
+    expect(() => {
+        ArrayBuffer();
+    }).toThrowWithMessage(TypeError, "ArrayBuffer constructor must be called with 'new'");
+});
+
+test("ArrayBuffer size limit", () => {
+    expect(() => {
+        new ArrayBuffer(2 ** 53);
+    }).toThrowWithMessage(RangeError, "Invalid array buffer length");
+});
+
+test("invalid ArrayBuffer maximum size option", () => {
+    expect(() => {
+        new ArrayBuffer(10, { maxByteLength: -1 });
+    }).toThrowWithMessage(RangeError, "Index must be a positive integer");
+});
+
+test("ArrayBuffer size exceeds maximum size", () => {
+    expect(() => {
+        new ArrayBuffer(10, { maxByteLength: 5 });
+    }).toThrowWithMessage(RangeError, "ArrayBuffer byte length of 10 exceeds the max byte length of 5");
+});