Add a test for pass through mode

Test: browser_tests --gtest_filter=ChromeVox*KeyboardHandler*.*
Change-Id: Ide1ec47e01e44c8bb635335883e01d68cff50b79
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2104263
Commit-Queue: David Tseng <dtseng@chromium.org>
Reviewed-by: Sara Kato <sarakato@chromium.org>
Cr-Commit-Position: refs/heads/master@{#750580}

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

@@ -3,7 +3,9 @@
 // found in the LICENSE file.
 
 // Include test fixture.
-GEN_INCLUDE(['../testing/chromevox_next_e2e_test_base.js']);
+GEN_INCLUDE([
+  '../testing/chromevox_next_e2e_test_base.js', '../testing/assert_additions.js'
+]);
 
 /**
  * Test fixture for ChromeVox KeyboardHandler.
@@ -13,6 +15,17 @@ ChromeVoxBackgroundKeyboardHandlerTest = class extends ChromeVoxNextE2ETest {
   setUp() {
     window.keyboardHandler = new BackgroundKeyboardHandler();
   }
+
+  createMockKeyEvent(keyCode, modifiers) {
+    const keyEvent = {};
+    keyEvent.keyCode = keyCode;
+    for (const key in modifiers) {
+      keyEvent[key] = modifiers[key];
+    }
+    keyEvent.preventDefault = _ => {};
+    keyEvent.stopPropagation = _ => {};
+    return keyEvent;
+  }
 };
 
 
@@ -36,3 +49,73 @@ TEST_F(
         assertEquals(1, keyboardHandler.eatenKeyDowns_.size);
       });
     });
+
+TEST_F('ChromeVoxBackgroundKeyboardHandlerTest', 'PassThroughMode', function() {
+  this.runWithLoadedTree('<p>test</p>', function() {
+    assertUndefined(ChromeVox.passThroughMode);
+    assertEquals(0, keyboardHandler.passThroughKeyUpCount_);
+    assertEquals(0, keyboardHandler.eatenKeyDowns_.size);
+
+    // Send the pass through command: Search+Shift+Escape.
+    const search = this.createMockKeyEvent(91, {metaKey: true});
+    keyboardHandler.onKeyDown(search);
+    assertEquals(1, keyboardHandler.eatenKeyDowns_.size);
+    assertUndefined(ChromeVox.passThroughMode);
+    assertEquals(0, keyboardHandler.passThroughKeyUpCount_);
+
+    const searchShift =
+        this.createMockKeyEvent(16, {metaKey: true, shiftKey: true});
+    keyboardHandler.onKeyDown(searchShift);
+    assertEquals(2, keyboardHandler.eatenKeyDowns_.size);
+    assertEquals(0, keyboardHandler.passThroughKeyUpCount_);
+    assertUndefined(ChromeVox.passThroughMode);
+
+    const searchShiftEsc =
+        this.createMockKeyEvent(27, {metaKey: true, shiftKey: true});
+    keyboardHandler.onKeyDown(searchShiftEsc);
+    assertEquals(3, keyboardHandler.eatenKeyDowns_.size);
+    assertEquals(0, keyboardHandler.passThroughKeyUpCount_);
+    assertTrue(ChromeVox.passThroughMode);
+
+    keyboardHandler.onKeyUp(searchShiftEsc);
+    assertEquals(2, keyboardHandler.eatenKeyDowns_.size);
+    assertEquals(1, keyboardHandler.passThroughKeyUpCount_);
+    assertTrue(ChromeVox.passThroughMode);
+
+    keyboardHandler.onKeyUp(searchShift);
+    assertEquals(1, keyboardHandler.eatenKeyDowns_.size);
+    assertEquals(2, keyboardHandler.passThroughKeyUpCount_);
+    assertTrue(ChromeVox.passThroughMode);
+
+    keyboardHandler.onKeyUp(search);
+    assertEquals(0, keyboardHandler.eatenKeyDowns_.size);
+    assertEquals(3, keyboardHandler.passThroughKeyUpCount_);
+    assertTrue(ChromeVox.passThroughMode);
+
+    // Now, the next series of key downs should be passed through.
+    // Try Search+Ctrl+M.
+    keyboardHandler.onKeyDown(search);
+    assertEquals(0, keyboardHandler.eatenKeyDowns_.size);
+    assertEquals(3, keyboardHandler.passThroughKeyUpCount_);
+    assertTrue(ChromeVox.passThroughMode);
+
+    const searchCtrl =
+        this.createMockKeyEvent(77, {metaKey: true, ctrlKey: true});
+    keyboardHandler.onKeyDown(searchCtrl);
+    assertEquals(0, keyboardHandler.eatenKeyDowns_.size);
+    assertEquals(3, keyboardHandler.passThroughKeyUpCount_);
+    assertTrue(ChromeVox.passThroughMode);
+
+    const searchCtrlM =
+        this.createMockKeyEvent(77, {metaKey: true, ctrlKey: true});
+    keyboardHandler.onKeyDown(searchCtrlM);
+    assertEquals(0, keyboardHandler.eatenKeyDowns_.size);
+    assertEquals(3, keyboardHandler.passThroughKeyUpCount_);
+    assertTrue(ChromeVox.passThroughMode);
+
+    keyboardHandler.onKeyUp(searchCtrlM);
+    assertEquals(0, keyboardHandler.eatenKeyDowns_.size);
+    assertEquals(0, keyboardHandler.passThroughKeyUpCount_);
+    assertFalse(ChromeVox.passThroughMode);
+  });
+});