Bug 1877469 - [webdriver-bidi] Await visibilitystatus change for previously selected tab when creating or switching tabs. r=webdriver-reviewers,Sasha

Differential Revision: https://phabricator.services.mozilla.com/D201061

remote/shared/RecommendedPreferences.sys.mjs

@@ -145,6 +145,9 @@ const COMMON_PREFERENCES = new Map([
   // Do not redirect user when a milstone upgrade of Firefox is detected
   ["browser.startup.homepage_override.mstone", "ignore"],
 
+  // Unload the previously selected tab immediately
+  ["browser.tabs.remote.unloadDelayMs", 0],
+
   // Don't unload tabs when available memory is running low
   ["browser.tabs.unloadOnLowMemory", false],
 

remote/test/puppeteer/test/TestExpectations.json

@@ -885,7 +885,7 @@
   {
     "testIdPattern": "[page.spec] Page Page.bringToFront should work",
     "platforms": ["darwin", "linux", "win32"],
-    "parameters": ["webDriverBiDi"],
+    "parameters": ["chrome", "webDriverBiDi"],
     "expectations": ["FAIL"]
   },
   {

remote/webdriver-bidi/modules/root/browsingContext.sys.mjs

@@ -232,11 +232,25 @@ class BrowsingContextModule extends Module {
       );
     }
 
-    const tab = lazy.TabManager.getTabForBrowsingContext(context);
-    const window = lazy.TabManager.getWindowForTab(tab);
+    const targetTab = lazy.TabManager.getTabForBrowsingContext(context);
+    const targetWindow = lazy.TabManager.getWindowForTab(targetTab);
+    const selectedTab = lazy.TabManager.getTabBrowser(targetWindow).selectedTab;
 
-    await lazy.windowManager.focusWindow(window);
-    await lazy.TabManager.selectTab(tab);
+    const activated = [
+      lazy.windowManager.focusWindow(targetWindow),
+      lazy.TabManager.selectTab(targetTab),
+    ];
+
+    if (targetTab !== selectedTab) {
+      // We need to wait until the "document.visibilityState" of the currently
+      // selected tab in the target window is marked as "hidden".
+      const selectedBrowser = lazy.TabManager.getBrowserForTab(selectedTab);
+      activated.push(
+        this.#waitForVisibilityChange(selectedBrowser.browsingContext)
+      );
+    }
+
+    await Promise.all(activated);
   }
 
   /**
@@ -547,17 +561,39 @@ class BrowsingContextModule extends Module {
           );
         }
 
+        // The window to open the new tab in.
+        let window = Services.wm.getMostRecentWindow(null);
+
         let referenceTab;
         if (referenceContext !== null) {
           referenceTab =
             lazy.TabManager.getTabForBrowsingContext(referenceContext);
+          window = lazy.TabManager.getWindowForTab(referenceTab);
         }
 
-        const tab = await lazy.TabManager.addTab({
-          focus: !background,
-          referenceTab,
-          userContextId: userContext,
-        });
+        const promises = [];
+
+        if (!background) {
+          // When opening a new foreground tab we need to wait until the
+          // "document.visibilityState" of the currently selected tab in this
+          // window is marked as "hidden".
+          const selectedTab = lazy.TabManager.getTabBrowser(window).selectedTab;
+          promises.push(
+            this.#waitForVisibilityChange(
+              lazy.TabManager.getBrowserForTab(selectedTab).browsingContext
+            )
+          );
+        }
+
+        promises.unshift(
+          lazy.TabManager.addTab({
+            focus: !background,
+            referenceTab,
+            userContextId: userContext,
+          })
+        );
+
+        const [tab] = await Promise.all(promises);
         browser = lazy.TabManager.getBrowserForTab(tab);
     }
 
@@ -1918,6 +1954,21 @@ class BrowsingContextModule extends Module {
     }
   }
 
+  #waitForVisibilityChange(browsingContext) {
+    return this.messageHandler.forwardCommand({
+      moduleName: "browsingContext",
+      commandName: "_awaitVisibilityState",
+      destination: {
+        type: lazy.WindowGlobalMessageHandler.type,
+        id: browsingContext.id,
+      },
+      params: {
+        value: "hidden",
+      },
+      retryOnAbort: true,
+    });
+  }
+
   /**
    * Internal commands
    */

remote/webdriver-bidi/modules/windowglobal/browsingContext.sys.mjs

@@ -17,6 +17,7 @@ ChromeUtils.defineESModuleGetters(lazy, {
     "chrome://remote/content/webdriver-bidi/modules/root/browsingContext.sys.mjs",
   OriginType:
     "chrome://remote/content/webdriver-bidi/modules/root/browsingContext.sys.mjs",
+  PollPromise: "chrome://remote/content/shared/Sync.sys.mjs",
 });
 
 const DOCUMENT_FRAGMENT_NODE = 11;
@@ -356,6 +357,29 @@ class BrowsingContextModule extends WindowGlobalBiDiModule {
     });
   }
 
+  /**
+   * Waits until the visibility state of the document has the expected value.
+   *
+   * @param {object} options
+   * @param {number} options.value
+   *     Expected value of the visibility state.
+   *
+   * @returns {Promise}
+   *     Promise that resolves when the visibility state has the expected value.
+   */
+  async _awaitVisibilityState(options) {
+    const { value } = options;
+    const win = this.messageHandler.window;
+
+    await lazy.PollPromise((resolve, reject) => {
+      if (win.document.visibilityState === value) {
+        resolve();
+      } else {
+        reject();
+      }
+    });
+  }
+
   _getBaseURL() {
     return this.messageHandler.window.document.baseURI;
   }