1 files changed, 74 insertions, 0 deletions
diff --git a/docshell/test/chrome/DocShellHelpers.sys.mjs b/docshell/test/chrome/DocShellHelpers.sys.mjs
new file mode 100644
index 0000000000..5f4eee8724
--- /dev/null
+++ b/docshell/test/chrome/DocShellHelpers.sys.mjs
@@ -0,0 +1,74 @@
+/* Any copyright is dedicated to the Public Domain.
+http://creativecommons.org/publicdomain/zero/1.0/ */
+
+export class DocShellHelpersParent extends JSWindowActorParent {
+  static eventListener;
+
+  // These static variables should be set when registering the actor
+  // (currently doPageNavigation in docshell_helpers.js).
+  static eventsToListenFor;
+  static observers;
+
+  constructor() {
+    super();
+  }
+  receiveMessage({ name, data }) {
+    if (name == "docshell_helpers:event") {
+      let { event, originalTargetIsHTMLDocument } = data;
+
+      if (this.constructor.eventsToListenFor.includes(event.type)) {
+        this.constructor.eventListener(event, originalTargetIsHTMLDocument);
+      }
+    } else if (name == "docshell_helpers:observe") {
+      let { topic } = data;
+
+      this.constructor.observers.get(topic).call();
+    }
+  }
+}
+
+export class DocShellHelpersChild extends JSWindowActorChild {
+  constructor() {
+    super();
+  }
+  receiveMessage({ name, data }) {
+    if (name == "docshell_helpers:preventBFCache") {
+      // Add an RTCPeerConnection to prevent the page from being bfcached.
+      let win = this.contentWindow;
+      win.blockBFCache = new win.RTCPeerConnection();
+    }
+  }
+  handleEvent(event) {
+    if (
+      Document.isInstance(event.originalTarget) &&
+      event.originalTarget.isInitialDocument
+    ) {
+      dump(`TEST: ignoring a ${event.type} event for an initial about:blank\n`);
+      return;
+    }
+
+    this.sendAsyncMessage("docshell_helpers:event", {
+      event: {
+        type: event.type,
+        persisted: event.persisted,
+        originalTarget: {
+          title: event.originalTarget.title,
+          location: event.originalTarget.location.href,
+          visibilityState: event.originalTarget.visibilityState,
+          hidden: event.originalTarget.hidden,
+        },
+      },
+      originalTargetIsHTMLDocument: HTMLDocument.isInstance(
+        event.originalTarget
+      ),
+    });
+  }
+  observe(subject, topic) {
+    if (Window.isInstance(subject) && subject.document.isInitialDocument) {
+      dump(`TEST: ignoring a topic notification for an initial about:blank\n`);
+      return;
+    }
+
+    this.sendAsyncMessage("docshell_helpers:observe", { topic });
+  }
+}