1 files changed, 157 insertions, 0 deletions
diff --git a/gfx/layers/apz/test/mochitest/FissionTestHelperChild.sys.mjs b/gfx/layers/apz/test/mochitest/FissionTestHelperChild.sys.mjs
new file mode 100644
index 0000000000..c0695b7abb
--- /dev/null
+++ b/gfx/layers/apz/test/mochitest/FissionTestHelperChild.sys.mjs
@@ -0,0 +1,157 @@
+// This code runs in the content process that holds the window to which
+// this actor is attached. There is one instance of this class for each
+// "inner window" (i.e. one per content document, including iframes/nested
+// iframes).
+// There is a 1:1 relationship between instances of this class and
+// FissionTestHelperParent instances, and the pair are entangled such
+// that they can communicate with each other regardless of which process
+// they live in.
+
+export class FissionTestHelperChild extends JSWindowActorChild {
+  constructor() {
+    super();
+    this._msgCounter = 0;
+    this._oopifResponsePromiseResolvers = [];
+  }
+
+  cw() {
+    return this.contentWindow.wrappedJSObject;
+  }
+
+  initialize() {
+    // This exports a bunch of things into the content window so that
+    // the test can access them. Most things are scoped inside the
+    // FissionTestHelper object on the window to avoid polluting the global
+    // namespace.
+
+    let cw = this.cw();
+    Cu.exportFunction(
+      (cond, msg) => this.sendAsyncMessage("ok", { cond, msg }),
+      cw,
+      { defineAs: "ok" }
+    );
+    Cu.exportFunction(
+      (a, b, msg) => this.sendAsyncMessage("is", { a, b, msg }),
+      cw,
+      { defineAs: "is" }
+    );
+
+    let FissionTestHelper = Cu.createObjectIn(cw, {
+      defineAs: "FissionTestHelper",
+    });
+    FissionTestHelper.startTestPromise = new cw.Promise(
+      Cu.exportFunction(resolve => {
+        this._startTestPromiseResolver = resolve;
+      }, cw)
+    );
+
+    Cu.exportFunction(this.subtestDone.bind(this), FissionTestHelper, {
+      defineAs: "subtestDone",
+    });
+
+    Cu.exportFunction(this.subtestFailed.bind(this), FissionTestHelper, {
+      defineAs: "subtestFailed",
+    });
+
+    Cu.exportFunction(this.sendToOopif.bind(this), FissionTestHelper, {
+      defineAs: "sendToOopif",
+    });
+    Cu.exportFunction(this.fireEventInEmbedder.bind(this), FissionTestHelper, {
+      defineAs: "fireEventInEmbedder",
+    });
+  }
+
+  // Called by the subtest to indicate completion to the top-level browser-chrome
+  // mochitest.
+  subtestDone() {
+    let cw = this.cw();
+    if (cw.ApzCleanup) {
+      cw.ApzCleanup.execute();
+    }
+    this.sendAsyncMessage("Test:Complete", {});
+  }
+
+  // Called by the subtest to indicate subtest failure. Only one of subtestDone
+  // or subtestFailed should be called.
+  subtestFailed(msg) {
+    this.sendAsyncMessage("ok", { cond: false, msg });
+    this.subtestDone();
+  }
+
+  // Called by the subtest to eval some code in the OOP iframe. This returns
+  // a promise that resolves to the return value from the eval.
+  sendToOopif(iframeElement, stringToEval) {
+    let browsingContextId = iframeElement.browsingContext.id;
+    let msgId = ++this._msgCounter;
+    let cw = this.cw();
+    let responsePromise = new cw.Promise(
+      Cu.exportFunction(resolve => {
+        this._oopifResponsePromiseResolvers[msgId] = resolve;
+      }, cw)
+    );
+    this.sendAsyncMessage("EmbedderToOopif", {
+      browsingContextId,
+      msgId,
+      stringToEval,
+    });
+    return responsePromise;
+  }
+
+  // Called by OOP iframes to dispatch an event in the embedder window. This
+  // can be used by the OOP iframe to asynchronously notify the embedder of
+  // things that happen. The embedder can use promiseOneEvent from
+  // helper_fission_utils.js to listen for these events.
+  fireEventInEmbedder(eventType, data) {
+    this.sendAsyncMessage("OopifToEmbedder", { eventType, data });
+  }
+
+  handleEvent(evt) {
+    switch (evt.type) {
+      case "FissionTestHelper:Init":
+        this.initialize();
+        break;
+    }
+  }
+
+  receiveMessage(msg) {
+    switch (msg.name) {
+      case "Test:Start":
+        this._startTestPromiseResolver();
+        delete this._startTestPromiseResolver;
+        break;
+      case "FromEmbedder":
+        let evalResult = this.contentWindow.eval(msg.data.stringToEval);
+        this.sendAsyncMessage("OopifToEmbedder", {
+          msgId: msg.data.msgId,
+          evalResult,
+        });
+        break;
+      case "FromOopif":
+        if (typeof msg.data.msgId == "number") {
+          if (!(msg.data.msgId in this._oopifResponsePromiseResolvers)) {
+            dump(
+              "Error: FromOopif got a message with unknown numeric msgId in " +
+                this.contentWindow.location.href +
+                "\n"
+            );
+          }
+          this._oopifResponsePromiseResolvers[msg.data.msgId](
+            msg.data.evalResult
+          );
+          delete this._oopifResponsePromiseResolvers[msg.data.msgId];
+        } else if (typeof msg.data.eventType == "string") {
+          let cw = this.cw();
+          let event = new cw.Event(msg.data.eventType);
+          event.data = Cu.cloneInto(msg.data.data, cw);
+          this.contentWindow.dispatchEvent(event);
+        } else {
+          dump(
+            "Warning: Unrecognized FromOopif message received in " +
+              this.contentWindow.location.href +
+              "\n"
+          );
+        }
+        break;
+    }
+  }
+}