ChromeVox: Announce when user executes a command when no focus is set.

Bug: 981964
Change-Id: I7953289c8aa2aacb5e7886990de243a2b29e131e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1951975
Commit-Queue: Akihiro Ota <akihiroota@chromium.org>
Reviewed-by: David Tseng <dtseng@chromium.org>
Cr-Commit-Position: refs/heads/master@{#747045}

chrome/browser/resources/chromeos/accessibility/chromevox/background/background.js

@@ -139,6 +139,9 @@ Background = class extends ChromeVoxState {
     /** @private {cursors.Range} */
     this.pageSel_;
 
+    /** @type {boolean} */
+    this.talkBackEnabled = false;
+
     CommandHandler.init();
     FindHandler.init();
     DownloadHandler.init();
@@ -152,6 +155,10 @@ Background = class extends ChromeVoxState {
         (announceText) => {
           ChromeVox.tts.speak(announceText.join(' '), QueueMode.FLUSH);
         });
+    chrome.accessibilityPrivate.onCustomSpokenFeedbackToggled.addListener(
+        (enabled) => {
+          this.talkBackEnabled = enabled;
+        });
 
     // Set the darkScreen state to false, since the display will be on whenever
     // ChromeVox starts.

chrome/browser/resources/chromeos/accessibility/chromevox/background/background_test.js

@@ -4,13 +4,10 @@
 
 // Include test fixture.
 GEN_INCLUDE([
-  '//chrome/browser/resources/chromeos/accessibility/chromevox/testing/chromevox_next_e2e_test_base.js',
-  '//chrome/browser/resources/chromeos/accessibility/chromevox/testing/assert_additions.js'
+  '../testing/chromevox_next_e2e_test_base.js', '../testing/assert_additions.js'
 ]);
 
-GEN_INCLUDE([
-  '//chrome/browser/resources/chromeos/accessibility/chromevox/testing/mock_feedback.js'
-]);
+GEN_INCLUDE(['../testing/mock_feedback.js', '../testing/fake_objects.js']);
 
 /**
  * Test fixture for Background.
@@ -137,6 +134,15 @@ ChromeVoxBackgroundTest = class extends ChromeVoxNextE2ETest {
       </div>
     `;
   }
+
+  /**
+   * Fires an onCustomSpokenFeedbackToggled event with enabled state of
+   * |enabled|.
+   * @param {boolean} enabled TalkBack-enabled state.
+   */
+  dispatchOnCustomSpokenFeedbackToggledEvent(enabled) {
+    chrome.accessibilityPrivate.onCustomSpokenFeedbackToggled.dispatch(enabled);
+  }
 };
 
 
@@ -1818,7 +1824,9 @@ TEST_F('ChromeVoxBackgroundTest', 'ListName', function() {
   const mockFeedback = this.createMockFeedback();
   this.runWithLoadedTree(
       `
-    <div id="_md-chips-wrapper-76" tabindex="-1" class="md-chips md-readonly" aria-setsize="4" aria-label="Favorite Sports" role="list" aria-describedby="chipsNote">
+    <div id="_md-chips-wrapper-76" tabindex="-1" class="md-chips md-readonly"
+        aria-setsize="4" aria-label="Favorite Sports" role="list"
+        aria-describedby="chipsNote">
       <div role="listitem">Baseball</div>
       <div role="listitem">Hockey</div>
       <div role="listitem">Lacrosse</div>
@@ -2362,3 +2370,44 @@ TEST_F('ChromeVoxBackgroundTest', 'ToggleDarkScreen', function() {
         .replay();
   });
 });
+
+TEST_F('ChromeVoxBackgroundTest', 'NoFocusTalkBackDisabled', function() {
+  // Fire onCustomSpokenFeedbackEnabled event to communicate that Talkback is
+  // off for the current app.
+  this.dispatchOnCustomSpokenFeedbackToggledEvent(false);
+  const mockFeedback = this.createMockFeedback();
+  this.runWithLoadedTree('<p>Test document</p>', function() {
+    ChromeVoxState.instance.setCurrentRange(null);
+    mockFeedback.call(doCmd('nextObject'))
+        .expectSpeech(
+            'No current ChromeVox focus. Press Alt+Shift+L to go to the ' +
+            'launcher.')
+        .call(doCmd('previousObject'))
+        .expectSpeech(
+            'No current ChromeVox focus. Press Alt+Shift+L to go to the ' +
+            'launcher.');
+    mockFeedback.replay();
+  });
+});
+
+TEST_F('ChromeVoxBackgroundTest', 'NoFocusTalkBackEnabled', function() {
+  // Fire onCustomSpokenFeedbackEnabled event to communicate that Talkback is
+  // on for the current app. We don't want to announce the no-focus hint message
+  // when TalkBack is on because we expect ChromeVox to have no focus in that
+  // case. If we announce the hint message, TalkBack and ChromeVox will
+  // try to speak at the same time.
+  this.dispatchOnCustomSpokenFeedbackToggledEvent(true);
+  const mockFeedback = this.createMockFeedback();
+  this.runWithLoadedTree('<p>Start here</p>', function() {
+    ChromeVoxState.instance.setCurrentRange(null);
+    mockFeedback.call(doCmd('nextObject'));
+    assertFalse(mockFeedback.utteranceInQueue(
+        'No current ChromeVox focus. ' +
+        'Press Alt+Shift+L to go to the launcher.'));
+    mockFeedback.call(doCmd('previousObject'));
+    assertFalse(mockFeedback.utteranceInQueue(
+        'No current ChromeVox focus. ' +
+        'Press Alt+Shift+L to go to the launcher.'));
+    mockFeedback.replay();
+  });
+});

chrome/browser/resources/chromeos/accessibility/chromevox/background/command_handler.js

@@ -270,6 +270,12 @@ CommandHandler.onCommand = function(command) {
 
   // Require a current range.
   if (!ChromeVoxState.instance.currentRange_) {
+    if (!ChromeVoxState.instance.talkBackEnabled) {
+      new Output()
+          .withString(Msgs.getMsg('no_focus'))
+          .withQueueMode(QueueMode.FLUSH)
+          .go();
+    }
     return true;
   }
 

chrome/browser/resources/chromeos/accessibility/chromevox/testing/mock_feedback.js

@@ -139,6 +139,20 @@ MockFeedback = class {
     ChromeVox.earcons = new MockEarcons();
   }
 
+  /**
+   * Returns true if |utterance| is in |pendingUtterances_|.
+   * @param {string} utterance
+   * @return {boolean}
+   */
+  utteranceInQueue(utterance) {
+    for (const pendingUtterance of this.pendingUtterances_) {
+      if (pendingUtterance.text === utterance) {
+        return true;
+      }
+    }
+    return false;
+  }
+
   /**
    * Adds an expectation for one or more spoken utterances.
    * @param {...(string|RegExp)} var_args One or more utterance to add as

chrome/browser/resources/chromeos/accessibility/strings/chromevox_strings.grdp

@@ -3699,5 +3699,8 @@
   <message desc="Title displayed in the panel for the form controls node menu." name="IDS_CHROMEVOX_PANEL_MENU_FORM_CONTROLS">
     Form Controls
   </message>
+  <message desc="Announced to alert the user that ChromeVox has no current focus." name="IDS_CHROMEVOX_NO_FOCUS">
+    No current ChromeVox focus. Press Alt+Shift+L to go to the launcher.
+  </message>
 
 </grit-part>