tor-browser

commit 22e501aa0ae6f19b439861b27355afc2349ab72e
parent 8ac9b654258da137a48005f179a897c15b5e8a24
Author: Henrik Skupin <mail@hskupin.info>
Date:   Thu,  6 Nov 2025 07:25:11 +0000

Bug 1996845 - [dom] Fix the replacement detection for the browsing-context-discarded notification. r=nika

Differential Revision: https://phabricator.services.mozilla.com/D271416

Diffstat:
M
docshell/base/BrowsingContext.cpp
 | 
2
+-
M
docshell/test/browser/browser_browsing_context_discarded.js
 | 
93
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-----------------

2 files changed, 74 insertions(+), 21 deletions(-)
diff --git a/docshell/base/BrowsingContext.cpp b/docshell/base/BrowsingContext.cpp
@@ -1115,7 +1115,7 @@ void BrowsingContext::Detach(bool aFromIPC) {
     // content process, but may be "replace" if it's known the context being
     // replaced in the parent process.
     const char16_t* why = u"discard";
-    if (XRE_IsParentProcess() && IsTop() && !Canonical()->GetWebProgress()) {
+    if (XRE_IsParentProcess() && Canonical()->IsReplaced()) {
       why = u"replace";
     }
     obs->NotifyObservers(ToSupports(this), "browsing-context-discarded", why);
diff --git a/docshell/test/browser/browser_browsing_context_discarded.js b/docshell/test/browser/browser_browsing_context_discarded.js
@@ -3,13 +3,13 @@
 const TOPIC = "browsing-context-discarded";
 
 async function observeDiscarded(browsingContexts, callback) {
-  let discarded = [];
+  let discarded = new Map();
 
-  let promise = BrowserUtils.promiseObserved(TOPIC, subject => {
+  let promise = BrowserUtils.promiseObserved(TOPIC, (subject, why) => {
     ok(BrowsingContext.isInstance(subject), "subject to be a BrowsingContext");
-    discarded.push(subject);
+    discarded.set(subject, why);
 
-    return browsingContexts.every(item => discarded.includes(item));
+    return browsingContexts.every(item => discarded.has(item));
   });
   await callback();
   await promise;
@@ -17,39 +17,64 @@ async function observeDiscarded(browsingContexts, callback) {
   return discarded;
 }
 
+function check_reason(discardedContexts, expected) {
+  discardedContexts.forEach((why, browsingContext) => {
+    if (expected.has(browsingContext)) {
+      is(why, expected.get(browsingContext));
+    }
+  });
+}
+
 add_task(async function toplevelForNewWindow() {
-  let win = await BrowserTestUtils.openNewBrowserWindow();
-  let browsingContext = win.gBrowser.selectedBrowser.browsingContext;
+  const win = await BrowserTestUtils.openNewBrowserWindow();
+  const browsingContext = win.gBrowser.selectedBrowser.browsingContext;
+
+  const expected = new Map([
+    [win.browsingContext, "discard"],
+    [browsingContext, "discard"],
+  ]);
 
-  await observeDiscarded([win.browsingContext, browsingContext], async () => {
+  const discarded = await observeDiscarded([...expected.keys()], async () => {
     await BrowserTestUtils.closeWindow(win);
   });
+
+  check_reason(discarded, expected);
 });
 
 add_task(async function toplevelForNewTab() {
-  let tab = await BrowserTestUtils.openNewForegroundTab(gBrowser);
-  let browsingContext = tab.linkedBrowser.browsingContext;
+  const tab = await BrowserTestUtils.openNewForegroundTab(gBrowser);
+  const browsingContext = tab.linkedBrowser.browsingContext;
+
+  const expected = new Map([[browsingContext, "discard"]]);
 
-  let discarded = await observeDiscarded([browsingContext], () => {
+  const discarded = await observeDiscarded([...expected.keys()], () => {
     BrowserTestUtils.removeTab(tab);
   });
 
   ok(
-    !discarded.includes(window.browsingContext),
+    !discarded.has(window.browsingContext),
     "no notification for the current window's chrome browsing context"
   );
+
+  check_reason(discarded, expected);
 });
 
 add_task(async function subframe() {
-  let tab = await BrowserTestUtils.openNewForegroundTab(gBrowser);
-  let 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;
-  });
+  const tab = await BrowserTestUtils.openNewForegroundTab(gBrowser);
+  const frameBrowsingContext = await SpecialPowers.spawn(
+    tab.linkedBrowser,
+    [],
+    () => {
+      const iframe = content.document.createElement("iframe");
+      content.document.body.appendChild(iframe);
+      iframe.contentWindow.location = "https://example.com/";
+      return iframe.browsingContext;
+    }
+  );
 
-  let discarded = await observeDiscarded([browsingContext], async () => {
+  const expected = new Map([[frameBrowsingContext, "discard"]]);
+
+  const discarded = await observeDiscarded([...expected.keys()], async () => {
     await SpecialPowers.spawn(tab.linkedBrowser, [], () => {
       let iframe = content.document.querySelector("iframe");
       iframe.remove();
@@ -57,9 +82,37 @@ add_task(async function subframe() {
   });
 
   ok(
-    !discarded.includes(tab.browsingContext),
+    !discarded.has(tab.linkedBrowser.browsingContext),
     "no notification for toplevel browsing context"
   );
+  ok(
+    !discarded.has(window.browsingContext),
+    "no notification for the current window's chrome browsing context"
+  );
+
+  check_reason(discarded, expected);
+
+  BrowserTestUtils.removeTab(tab);
+});
+
+add_task(async function replaceToplevel() {
+  const tab = await BrowserTestUtils.openNewForegroundTab(gBrowser);
+  const browsingContext = tab.linkedBrowser.browsingContext;
+
+  const expected = new Map([[browsingContext, "replace"]]);
+
+  const discarded = await observeDiscarded([...expected.keys()], async () => {
+    await SpecialPowers.spawn(tab.linkedBrowser, [], () => {
+      content.location = "about:newtab";
+    });
+  });
+
+  ok(
+    !discarded.has(window.browsingContext),
+    "no notification for the current window's chrome browsing context"
+  );
+
+  check_reason(discarded, expected);
 
   BrowserTestUtils.removeTab(tab);
 });