1 files changed, 129 insertions, 0 deletions
diff --git a/browser/base/content/test/performance/browser_appmenu.js b/browser/base/content/test/performance/browser_appmenu.js
new file mode 100644
index 0000000000..3d554d8881
--- /dev/null
+++ b/browser/base/content/test/performance/browser_appmenu.js
@@ -0,0 +1,129 @@
+"use strict";
+/* global PanelUI */
+
+const { CustomizableUITestUtils } = ChromeUtils.importESModule(
+  "resource://testing-common/CustomizableUITestUtils.sys.mjs"
+);
+let gCUITestUtils = new CustomizableUITestUtils(window);
+
+/**
+ * WHOA THERE: We should never be adding new things to
+ * EXPECTED_APPMENU_OPEN_REFLOWS. This list should slowly go
+ * away as we improve the performance of the front-end. Instead of adding more
+ * reflows to the list, you should be modifying your code to avoid the reflow.
+ *
+ * See https://firefox-source-docs.mozilla.org/performance/bestpractices.html
+ * for tips on how to do that.
+ */
+const EXPECTED_APPMENU_OPEN_REFLOWS = [
+  {
+    stack: [
+      "openPopup/this._openPopupPromise<@resource:///modules/PanelMultiView.sys.mjs",
+    ],
+  },
+
+  {
+    stack: [
+      "_calculateMaxHeight@resource:///modules/PanelMultiView.sys.mjs",
+      "handleEvent@resource:///modules/PanelMultiView.sys.mjs",
+    ],
+
+    maxCount: 7, // This number should only ever go down - never up.
+  },
+];
+
+add_task(async function () {
+  await ensureNoPreloadedBrowser();
+  await disableFxaBadge();
+
+  let textBoxRect = gURLBar
+    .querySelector("moz-input-box")
+    .getBoundingClientRect();
+  let menuButtonRect = document
+    .getElementById("PanelUI-menu-button")
+    .getBoundingClientRect();
+  let firstTabRect = gBrowser.selectedTab.getBoundingClientRect();
+  let frameExpectations = {
+    filter: rects => {
+      // We expect the menu button to get into the active state.
+      //
+      // XXX For some reason the menu panel isn't in our screenshots, but
+      // that's where we actually expect many changes.
+      return rects.filter(r => !rectInBoundingClientRect(r, menuButtonRect));
+    },
+    exceptions: [
+      {
+        name: "the urlbar placeholder moves up and down by a few pixels",
+        condition: r => rectInBoundingClientRect(r, textBoxRect),
+      },
+      {
+        name: "bug 1547341 - a first tab gets drawn early",
+        condition: r => rectInBoundingClientRect(r, firstTabRect),
+      },
+    ],
+  };
+
+  // First, open the appmenu.
+  await withPerfObserver(() => gCUITestUtils.openMainMenu(), {
+    expectedReflows: EXPECTED_APPMENU_OPEN_REFLOWS,
+    frames: frameExpectations,
+  });
+
+  // Now open a series of subviews, and then close the appmenu. We
+  // should not reflow during any of this.
+  await withPerfObserver(
+    async function () {
+      // This recursive function will take the current main or subview,
+      // find all of the buttons that navigate to subviews inside it,
+      // and click each one individually. Upon entering the new view,
+      // we recurse. When the subviews within a view have been
+      // exhausted, we go back up a level.
+      async function openSubViewsRecursively(currentView) {
+        let navButtons = Array.from(
+          // Ensure that only enabled buttons are tested
+          currentView.querySelectorAll(".subviewbutton-nav:not([disabled])")
+        );
+        if (!navButtons) {
+          return;
+        }
+
+        for (let button of navButtons) {
+          info("Click " + button.id);
+          let promiseViewShown = BrowserTestUtils.waitForEvent(
+            PanelUI.panel,
+            "ViewShown"
+          );
+          button.click();
+          let viewShownEvent = await promiseViewShown;
+
+          // Workaround until bug 1363756 is fixed, then this can be removed.
+          let container = PanelUI.multiView.querySelector(
+            ".panel-viewcontainer"
+          );
+          await TestUtils.waitForCondition(() => {
+            return !container.hasAttribute("width");
+          });
+
+          info("Shown " + viewShownEvent.originalTarget.id);
+          await openSubViewsRecursively(viewShownEvent.originalTarget);
+          promiseViewShown = BrowserTestUtils.waitForEvent(
+            currentView,
+            "ViewShown"
+          );
+          PanelUI.multiView.goBack();
+          await promiseViewShown;
+
+          // Workaround until bug 1363756 is fixed, then this can be removed.
+          await TestUtils.waitForCondition(() => {
+            return !container.hasAttribute("width");
+          });
+        }
+      }
+
+      await openSubViewsRecursively(PanelUI.mainView);
+
+      await gCUITestUtils.hideMainMenu();
+    },
+    { expectedReflows: [], frames: frameExpectations }
+  );
+});