Adding upstream version 86.0.1.upstream/86.0.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 112 insertions, 0 deletions

diff --git a/browser/base/content/test/performance/browser_tabswitch.js b/browser/base/content/test/performance/browser_tabswitch.js
new file mode 100644
index 0000000000..de67bbe330
--- /dev/null
+++ b/browser/base/content/test/performance/browser_tabswitch.js
@@ -0,0 +1,112 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+/**
+ * WHOA THERE: We should never be adding new things to EXPECTED_REFLOWS.
+ * Instead of adding reflows to the list, you should be modifying your code to
+ * avoid the reflow.
+ *
+ * See https://developer.mozilla.org/en-US/Firefox/Performance_best_practices_for_Firefox_fe_engineers
+ * for tips on how to do that.
+ */
+const EXPECTED_REFLOWS = [
+  /**
+   * Nothing here! Please don't add anything new!
+   */
+];
+
+/*
+ * This test ensures that there are no unexpected
+ * uninterruptible reflows when switching between two
+ * tabs that are both fully visible.
+ */
+add_task(async function() {
+  await ensureNoPreloadedBrowser();
+  await disableFxaBadge();
+
+  // The test starts on about:blank and opens an about:blank
+  // tab which triggers opening the toolbar since
+  // ensureNoPreloadedBrowser sets AboutNewTab.newTabURL to about:blank.
+  await SpecialPowers.pushPrefEnv({
+    set: [["browser.toolbars.bookmarks.visibility", "never"]],
+  });
+
+  // At the time of writing, there are no reflows on simple tab switching.
+  // Mochitest will fail if we have no assertions, so we add one here
+  // to make sure nobody adds any new ones.
+  Assert.equal(
+    EXPECTED_REFLOWS.length,
+    0,
+    "We shouldn't have added any new expected reflows."
+  );
+
+  let origTab = gBrowser.selectedTab;
+  let firstSwitchDone = BrowserTestUtils.waitForEvent(window, "TabSwitchDone");
+  let otherTab = await BrowserTestUtils.openNewForegroundTab(gBrowser);
+  await firstSwitchDone;
+
+  let tabStripRect = gBrowser.tabContainer.arrowScrollbox.getBoundingClientRect();
+  let firstTabRect = origTab.getBoundingClientRect();
+  let inRange = (val, min, max) => min <= val && val <= max;
+
+  await withPerfObserver(
+    async function() {
+      let switchDone = BrowserTestUtils.waitForEvent(window, "TabSwitchDone");
+      gBrowser.selectedTab = origTab;
+      await switchDone;
+    },
+    {
+      expectedReflows: EXPECTED_REFLOWS,
+      frames: {
+        filter: rects =>
+          rects.filter(
+            r =>
+              !(
+                // We expect all changes to be within the tab strip.
+                (
+                  r.y1 >= tabStripRect.top &&
+                  r.y2 <= tabStripRect.bottom &&
+                  r.x1 >= tabStripRect.left &&
+                  r.x2 <= tabStripRect.right &&
+                  // The tab selection changes between 2 adjacent tabs, so we expect
+                  // both to change color at once: this should be a single rect of the
+                  // width of 2 tabs.
+                  inRange(
+                    r.w,
+                    (origTab.clientWidth - 1) * 2, // -1 for the border on Win7
+                    origTab.clientWidth * 2
+                  )
+                )
+              )
+          ),
+        exceptions: [
+          {
+            name:
+              "bug 1446454 - the border between tabs should be painted at" +
+              " the same time as the tab switch",
+            condition: r =>
+              // In tab strip
+              r.y1 >= tabStripRect.top &&
+              r.y2 <= tabStripRect.bottom &&
+              // 1px border, 1px before the end of the first tab.
+              r.w == 1 &&
+              r.x1 == firstTabRect.right - 1,
+          },
+          {
+            name: "bug 1446449 - spurious tab switch spinner",
+            condition: r =>
+              AppConstants.DEBUG &&
+              // In the content area
+              r.y1 >=
+                document.getElementById("appcontent").getBoundingClientRect()
+                  .top,
+          },
+        ],
+      },
+    }
+  );
+
+  BrowserTestUtils.removeTab(otherTab);
+});