1 files changed, 179 insertions, 0 deletions
diff --git a/docshell/test/browser/browser_browsing_context_attached.js b/docshell/test/browser/browser_browsing_context_attached.js
new file mode 100644
index 0000000000..60ef5e4aa6
--- /dev/null
+++ b/docshell/test/browser/browser_browsing_context_attached.js
@@ -0,0 +1,179 @@
+"use strict";
+
+const TEST_PATH =
+  getRootDirectory(gTestPath).replace(
+    "chrome://mochitests/content",
+    // eslint-disable-next-line @microsoft/sdl/no-insecure-url
+    "http://example.com"
+  ) + "dummy_page.html";
+
+const TOPIC = "browsing-context-attached";
+
+async function observeAttached(callback) {
+  let attached = new Map();
+
+  function observer(subject, topic, data) {
+    is(topic, TOPIC, "observing correct topic");
+    ok(BrowsingContext.isInstance(subject), "subject to be a BrowsingContext");
+    is(typeof data, "string", "data to be a String");
+    info(`*** bc id=${subject.id}, why=${data}`);
+    attached.set(subject.id, { browsingContext: subject, why: data });
+  }
+
+  Services.obs.addObserver(observer, TOPIC);
+  try {
+    await callback();
+    return attached;
+  } finally {
+    Services.obs.removeObserver(observer, TOPIC);
+  }
+}
+
+add_task(async function toplevelForNewWindow() {
+  let win;
+
+  let attached = await observeAttached(async () => {
+    win = await BrowserTestUtils.openNewBrowserWindow();
+  });
+
+  ok(
+    attached.has(win.browsingContext.id),
+    "got notification for window's chrome browsing context"
+  );
+  is(
+    attached.get(win.browsingContext.id).why,
+    "attach",
+    "expected reason for chrome browsing context"
+  );
+
+  ok(
+    attached.has(win.gBrowser.selectedBrowser.browsingContext.id),
+    "got notification for toplevel browsing context"
+  );
+  is(
+    attached.get(win.gBrowser.selectedBrowser.browsingContext.id).why,
+    "attach",
+    "expected reason for toplevel browsing context"
+  );
+
+  await BrowserTestUtils.closeWindow(win);
+});
+
+add_task(async function toplevelForNewTab() {
+  let tab;
+
+  let attached = await observeAttached(async () => {
+    tab = await BrowserTestUtils.openNewForegroundTab(gBrowser);
+  });
+
+  ok(
+    !attached.has(window.browsingContext.id),
+    "no notification for the current window's chrome browsing context"
+  );
+  ok(
+    attached.has(tab.linkedBrowser.browsingContext.id),
+    "got notification for toplevel browsing context"
+  );
+  is(
+    attached.get(tab.linkedBrowser.browsingContext.id).why,
+    "attach",
+    "expected reason for toplevel browsing context"
+  );
+
+  BrowserTestUtils.removeTab(tab);
+});
+
+add_task(async function subframe() {
+  let browsingContext;
+  let tab = await BrowserTestUtils.openNewForegroundTab(gBrowser);
+
+  let attached = await observeAttached(async () => {
+    browsingContext = await SpecialPowers.spawn(tab.linkedBrowser, [], () => {
+      let iframe = content.document.createElement("iframe");
+      content.document.body.appendChild(iframe);
+      iframe.contentWindow.location = "https://example.com/";
+      return iframe.browsingContext;
+    });
+  });
+
+  ok(
+    !attached.has(window.browsingContext.id),
+    "no notification for the current window's chrome browsing context"
+  );
+  ok(
+    !attached.has(tab.linkedBrowser.browsingContext.id),
+    "no notification for toplevel browsing context"
+  );
+  ok(
+    attached.has(browsingContext.id),
+    "got notification for frame's browsing context"
+  );
+  is(
+    attached.get(browsingContext.id).why,
+    "attach",
+    "expected reason for frame's browsing context"
+  );
+
+  BrowserTestUtils.removeTab(tab);
+});
+
+add_task(async function toplevelReplacedBy() {
+  let tab;
+
+  let attached = await observeAttached(async () => {
+    tab = await BrowserTestUtils.openNewForegroundTab(gBrowser, "about:robots");
+  });
+
+  const firstContext = tab.linkedBrowser.browsingContext;
+  ok(
+    attached.has(firstContext.id),
+    "got notification for initial toplevel browsing context"
+  );
+  is(
+    attached.get(firstContext.id).why,
+    "attach",
+    "expected reason for initial toplevel browsing context"
+  );
+
+  attached = await observeAttached(async () => {
+    await loadURI(TEST_PATH);
+  });
+  const secondContext = tab.linkedBrowser.browsingContext;
+  ok(
+    attached.has(secondContext.id),
+    "got notification for replaced toplevel browsing context"
+  );
+  isnot(secondContext, firstContext, "browsing context to be replaced");
+  is(
+    attached.get(secondContext.id).why,
+    "replace",
+    "expected reason for replaced toplevel browsing context"
+  );
+  is(
+    secondContext.browserId,
+    firstContext.browserId,
+    "browserId has been kept"
+  );
+
+  attached = await observeAttached(async () => {
+    await loadURI("about:robots");
+  });
+  const thirdContext = tab.linkedBrowser.browsingContext;
+  ok(
+    attached.has(thirdContext.id),
+    "got notification for replaced toplevel browsing context"
+  );
+  isnot(thirdContext, secondContext, "browsing context to be replaced");
+  is(
+    attached.get(thirdContext.id).why,
+    "replace",
+    "expected reason for replaced toplevel browsing context"
+  );
+  is(
+    thirdContext.browserId,
+    secondContext.browserId,
+    "browserId has been kept"
+  );
+
+  BrowserTestUtils.removeTab(tab);
+});