1 files changed, 90 insertions, 0 deletions
diff --git a/dom/ipc/tests/test_child_docshell.js b/dom/ipc/tests/test_child_docshell.js
new file mode 100644
index 0000000000..ee79a509dc
--- /dev/null
+++ b/dom/ipc/tests/test_child_docshell.js
@@ -0,0 +1,90 @@
+"use strict";
+
+const { XPCShellContentUtils } = ChromeUtils.importESModule(
+  "resource://testing-common/XPCShellContentUtils.sys.mjs"
+);
+
+XPCShellContentUtils.init(this);
+
+add_task(async function test() {
+  let page = await XPCShellContentUtils.loadContentPage("about:blank", {
+    remote: true,
+  });
+
+  await new Promise(resolve => {
+    let mm = page.browser.messageManager;
+    mm.addMessageListener("chromeEventHandler", function (msg) {
+      var result = msg.json;
+      equal(
+        result.processType,
+        Ci.nsIXULRuntime.PROCESS_TYPE_CONTENT,
+        "The frame script is running in a real distinct child process"
+      );
+      ok(
+        result.hasCorrectInterface,
+        "docshell.chromeEventHandler has EventTarget interface"
+      );
+    });
+
+    mm.addMessageListener("DOMWindowCreatedReceived", function (msg) {
+      ok(true, "the chrome event handler looks functional");
+      var result = msg.json;
+      ok(
+        result.stableChromeEventHandler,
+        "docShell.chromeEventHandler is stable"
+      );
+      ok(result.iframeHasNewDocShell, "iframe spawns a new docShell");
+      ok(
+        result.iframeHasSameChromeEventHandler,
+        "but iframe has the same chrome event handler"
+      );
+      resolve();
+    });
+
+    // Inject a frame script in the child process:
+    page.loadFrameScript(async function () {
+      /* eslint-env mozilla/frame-script */
+      var chromeEventHandler = docShell.chromeEventHandler;
+      sendAsyncMessage("chromeEventHandler", {
+        processType: Services.appinfo.processType,
+        hasCorrectInterface:
+          chromeEventHandler && EventTarget.isInstance(chromeEventHandler),
+      });
+
+      /*
+        Ensure that this chromeEventHandler actually works,
+        by creating a new window and listening for its DOMWindowCreated event
+      */
+      chromeEventHandler.addEventListener(
+        "DOMWindowCreated",
+        function listener(evt) {
+          if (evt.target == content.document) {
+            return;
+          }
+          chromeEventHandler.removeEventListener("DOMWindowCreated", listener);
+          let new_win = evt.target.defaultView;
+          let new_docShell = new_win.docShell;
+          sendAsyncMessage("DOMWindowCreatedReceived", {
+            stableChromeEventHandler:
+              chromeEventHandler === docShell.chromeEventHandler,
+            iframeHasNewDocShell: new_docShell !== docShell,
+            iframeHasSameChromeEventHandler:
+              new_docShell.chromeEventHandler === chromeEventHandler,
+          });
+        }
+      );
+
+      if (content.document.readyState != "complete") {
+        await new Promise(res =>
+          addEventListener("load", res, { once: true, capture: true })
+        );
+      }
+
+      let iframe = content.document.createElement("iframe");
+      iframe.setAttribute("src", "data:text/html,foo");
+      content.document.documentElement.appendChild(iframe);
+    });
+  });
+
+  await page.close();
+});