Bug 1908019 - Store sidebar UI state in a pref that acts as a fallback r=sidebar-reviewers,sessionstore-reviewers,sfoster

Refactor sidebar state persistence logic outside of SessionStore and into SidebarController and SidebarManager. Expose an API for session store to update state. If session store data is not available, use the backup state instead. Works for both "Never remember history" and "Use custom settings for history".

Differential Revision: https://phabricator.services.mozilla.com/D225220

browser/app/profile/firefox.js

@@ -1991,6 +1991,10 @@ pref("sidebar.animation.duration-ms", 200);
 pref("sidebar.main.tools", "aichat,syncedtabs,history");
 pref("sidebar.verticalTabs", false);
 pref("sidebar.visibility", "always-show");
+// Sidebar UI state is stored per-window via session restore. Use this pref
+// as a backup to restore the sidebar UI state when a user has PPB mode on
+// or has history cleared on browser close.
+pref("sidebar.backupState", "{}");
 
 pref("browser.ml.chat.enabled", false);
 pref("browser.ml.chat.hideLocalhost", true);

browser/components/sessionstore/SessionStore.sys.mjs

@@ -4557,24 +4557,7 @@ var SessionStoreInternal = {
       delete winData.hidden;
     }
 
-    let sidebarBox = aWindow.document.getElementById("sidebar-box");
-    let command = sidebarBox.getAttribute("sidebarcommand");
-    winData.sidebar = {};
-    if (sidebarBox.style.width) {
-      winData.sidebar.width = sidebarBox.style.width;
-    }
-    if (command && sidebarBox.getAttribute("checked") == "true") {
-      winData.sidebar.command = command;
-    } else if (winData.sidebar?.command) {
-      delete winData.sidebar.command;
-    }
-
-    if (aWindow.SidebarController.revampComponentsLoaded) {
-      winData.sidebar = Object.assign(winData.sidebar || {}, {
-        expanded: aWindow.SidebarController.sidebarMain.expanded,
-        hidden: aWindow.SidebarController.sidebarContainer.hidden,
-      });
-    }
+    winData.sidebar = aWindow.SidebarController.getUIState();
 
     let workspaceID = aWindow.getWorkspaceID();
     if (workspaceID) {
@@ -5632,30 +5615,8 @@ var SessionStoreInternal = {
    *        Object containing command (sidebarcommand/category) and styles
    */
   restoreSidebar(aWindow, aSidebar, isPopup) {
-    if (!aSidebar) {
-      return;
-    }
     if (!isPopup) {
-      let sidebarBox = aWindow.document.getElementById("sidebar-box");
-      // Always restore sidebar width
-      if (aSidebar.width) {
-        sidebarBox.style.width = aSidebar.width;
-      }
-      if (
-        aSidebar.command &&
-        (sidebarBox.getAttribute("sidebarcommand") != aSidebar.command ||
-          !sidebarBox.getAttribute("checked"))
-      ) {
-        aWindow.SidebarController.showInitially(aSidebar.command);
-      }
-    }
-    if (aWindow.SidebarController.sidebarRevampEnabled) {
-      const { SidebarController } = aWindow;
-      SidebarController.promiseInitialized.then(() => {
-        SidebarController.toggleExpanded(aSidebar.expanded);
-        SidebarController.sidebarContainer.hidden = aSidebar.hidden;
-        SidebarController.updateToolbarButton();
-      });
+      aWindow.SidebarController.setUIState(aSidebar);
     }
   },
 

browser/components/sessionstore/test/marionette/test_restore_sidebar.py

@@ -246,3 +246,44 @@ class TestSessionRestore(SessionStoreTestCase):
             ),
             "Sidebar visibility state has been restored.",
         )
+
+    def test_restore_sidebar_open_from_backup_pref(self):
+        self.marionette.execute_script(
+            """
+            Services.prefs.setBoolPref("sidebar.revamp", true);
+            Services.prefs.setBoolPref("browser.privatebrowsing.autostart", true);
+            """
+        )
+        self.marionette.restart()
+        self.marionette.set_context("chrome")
+
+        # Open the history panel.
+        self.marionette.execute_async_script(
+            """
+            let resolve = arguments[0];
+            let window = BrowserWindowTracker.getTopWindow();
+            window.SidebarController.show("viewHistorySidebar").then(resolve);
+            """
+        )
+
+        # Restart the browser.
+        self.marionette.restart()
+        self.marionette.execute_async_script(
+            """
+            let resolve = arguments[0];
+            let { BrowserInitState } = ChromeUtils.importESModule("resource:///modules/BrowserGlue.sys.mjs");
+            BrowserInitState.startupIdleTaskPromise.then(resolve);
+            """
+        )
+
+        # Check to see if the history panel was restored.
+        self.assertEqual(
+            self.marionette.execute_script(
+                """
+                let window = BrowserWindowTracker.getTopWindow();
+                return window.SidebarController.currentID;
+                """
+            ),
+            "viewHistorySidebar",
+            "Correct sidebar category has been restored.",
+        )

browser/components/sidebar/SidebarManager.sys.mjs

@@ -5,6 +5,8 @@
 import { AppConstants } from "resource://gre/modules/AppConstants.sys.mjs";
 import { XPCOMUtils } from "resource://gre/modules/XPCOMUtils.sys.mjs";
 
+const BACKUP_STATE_PREF = "sidebar.backupState";
+
 const lazy = {};
 ChromeUtils.defineESModuleGetters(lazy, {
   ExperimentAPI: "resource://nimbus/ExperimentAPI.sys.mjs",
@@ -12,6 +14,11 @@ ChromeUtils.defineESModuleGetters(lazy, {
   PrefUtils: "resource://normandy/lib/PrefUtils.sys.mjs",
 });
 XPCOMUtils.defineLazyPreferenceGetter(lazy, "sidebarNimbus", "sidebar.nimbus");
+XPCOMUtils.defineLazyPreferenceGetter(
+  lazy,
+  "sidebarBackupState",
+  BACKUP_STATE_PREF
+);
 
 export const SidebarManager = {
   /**
@@ -60,6 +67,35 @@ export const SidebarManager = {
       );
     });
   },
+
+  /**
+   * Provide a system-level "backup" state to be stored for those using "Never
+   * remember history" or "Clear history when browser closes".
+   *
+   * If it doesn't exist or isn't parsable, return `null`.
+   *
+   * @returns {object}
+   */
+  getBackupState() {
+    try {
+      return JSON.parse(lazy.sidebarBackupState);
+    } catch (e) {
+      Services.prefs.clearUserPref(BACKUP_STATE_PREF);
+      return null;
+    }
+  },
+
+  /**
+   * Set the backup state.
+   *
+   * @param {object} state
+   */
+  setBackupState(state) {
+    if (!state) {
+      return;
+    }
+    Services.prefs.setStringPref(BACKUP_STATE_PREF, JSON.stringify(state));
+  },
 };
 
 // Initialize on first import

browser/components/sidebar/browser-sidebar.js

@@ -408,6 +408,14 @@ var SidebarController = {
       this._tabstripOrientationObserverAdded = true;
     }
 
+    requestIdleCallback(() => {
+      if (!this._uiState) {
+        // UI state has not been set by SessionStore. Use backup state for now.
+        const backupState = this.SidebarManager.getBackupState();
+        this.setUIState(backupState);
+      }
+    });
+
     this._initDeferred.resolve();
   },
 
@@ -420,8 +428,10 @@ var SidebarController = {
     let enumerator = Services.wm.getEnumerator("navigator:browser");
     if (!enumerator.hasMoreElements()) {
       let xulStore = Services.xulStore;
-
       xulStore.persist(this._title, "value");
+
+      const currentState = this.getUIState();
+      this.SidebarManager.setBackupState(currentState);
     }
 
     Services.obs.removeObserver(this, "intl:app-locales-changed");
@@ -446,6 +456,50 @@ var SidebarController = {
     this.browser.removeEventListener("resize", this._browserResizeObserver);
   },
 
+  getUIState() {
+    const state = { width: this._box.style.width, command: this.currentID };
+    if (this.sidebarRevampEnabled) {
+      state.expanded = this.sidebarMain.expanded;
+      state.hidden = this.sidebarContainer.hidden;
+    }
+    return state;
+  },
+
+  /**
+   * Update and store the UI state of the sidebar for this window.
+   *
+   * @param {object} state
+   * @param {string} state.width
+   *   Panel width of the sidebar.
+   * @param {string} state.command
+   *   Panel ID that is currently open.
+   * @param {boolean} state.expanded
+   *   Whether the sidebar launcher is expanded. (Revamp only)
+   * @param {boolean} state.hidden
+   *   Whether the sidebar is hidden. (Revamp only)
+   */
+  async setUIState(state) {
+    if (!state) {
+      return;
+    }
+    this._uiState = state;
+    if (state.width) {
+      this._box.style.width = state.width;
+    }
+    if (state.command && this.currentID != state.command && !this.isOpen) {
+      await this.showInitially(state.command);
+    }
+    if (this.sidebarRevampEnabled) {
+      // The `sidebar-main` component is lazy-loaded in the `init()` method.
+      // Wait this out to ensure that it is connected to the DOM before making
+      // any changes.
+      await this.promiseInitialized;
+      this.toggleExpanded(state.expanded);
+      this.sidebarContainer.hidden = state.hidden;
+      this.updateToolbarButton();
+    }
+  },
+
   /**
    * The handler for Services.obs.addObserver.
    */
@@ -692,29 +746,8 @@ var SidebarController = {
       this._box.setAttribute("sidebarcommand", commandID);
     }
 
-    // Adopt `expanded` and `hidden` states only if the opener was also using
-    // revamped sidebar.
-    if (this.sidebarRevampEnabled && sourceController.revampComponentsLoaded) {
-      this.promiseInitialized.then(() => {
-        this.sidebarContainer.hidden = sourceController.sidebarContainer.hidden;
-        this.toggleExpanded(sourceController.sidebarMain.expanded);
-      });
-    }
-
-    if (sourceController._box.hidden) {
-      // just hidden means we have adopted the hidden state.
-      return true;
-    }
-
-    // dynamically generated sidebars will fail this check, but we still
-    // consider it adopted.
-    if (!this.sidebars.has(commandID)) {
-      return true;
-    }
-
-    this._box.style.width = sourceController._box.style.width;
-    this.showInitially(commandID);
-
+    const sourceControllerState = sourceController.getUIState();
+    this.setUIState(sourceControllerState);
     return true;
   },