MacViews a11y: Support the "Show menu" action in Textfield and Combobox.

ui/views/widget/native_widget_mac_accessibility_unittest.mm

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <memory>
 
 #import <Cocoa/Cocoa.h>
 
 #include "base/mac/mac_util.h"
 #import "base/mac/sdk_forward_declarations.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/sys_string_conversions.h"
 #include "base/strings/utf_string_conversions.h"
 #import "testing/gtest_mac.h"
 #include "ui/accessibility/ax_enums.h"
 #include "ui/accessibility/ax_node_data.h"
 #import "ui/accessibility/platform/ax_platform_node_mac.h"
 #include "ui/base/ime/text_input_type.h"
 #import "ui/gfx/mac/coordinate_conversion.h"
 #include "ui/views/controls/button/label_button.h"
+#include "ui/views/controls/combobox/combobox.h"
 #include "ui/views/controls/label.h"
 #include "ui/views/controls/textfield/textfield.h"
 #include "ui/views/test/widget_test.h"
 #include "ui/views/widget/widget.h"
 
 // Expose some methods from AXPlatformNodeCocoa for testing purposes only.
 @interface AXPlatformNodeCocoa (Testing)
 - (NSString*)AXRole;
 - (id)AXValue;
 
@@ skipping 282 matching lines @@
 
   // Test accessibility clients can see subroles as well.
   textfield->SetTextInputType(ui::TEXT_INPUT_TYPE_PASSWORD);
   EXPECT_NSEQ(NSAccessibilitySecureTextFieldSubrole,
               AttributeValueAtMidpoint(NSAccessibilitySubroleAttribute));
   role_description = NSAccessibilityRoleDescription(
       NSAccessibilityTextFieldRole, NSAccessibilitySecureTextFieldSubrole);
   EXPECT_NSEQ(role_description, AttributeValueAtMidpoint(
                                     NSAccessibilityRoleDescriptionAttribute));
 
+  // Expect to see the action to show a context menu.
+  EXPECT_NSEQ(@[ NSAccessibilityShowMenuAction ],
+              [A11yElementAtMidpoint() accessibilityActionNames]);
+
   // Prevent the textfield from interfering with hit tests on the widget itself.
   widget()->GetContentsView()->RemoveChildView(textfield);
 
   // NSAccessibilitySizeAttribute.
   EXPECT_EQ(GetWidgetBounds().size(),
             gfx::Size([AttributeValueAtMidpoint(NSAccessibilitySizeAttribute)
                 sizeValue]));
   // Check the attribute is updated when the Widget is resized.
   gfx::Size new_size(200, 40);
   widget()->SetSize(new_size);
@@ skipping 393 matching lines @@
   EXPECT_NSEQ(@"", [ax_node AXSelectedText]);
   EXPECT_NSEQ([NSValue valueWithRange:NSMakeRange(0, 0)],
               [ax_node AXSelectedTextRange]);
 
   EXPECT_EQ(kTestStringLength, [[ax_node AXNumberOfCharacters] intValue]);
   EXPECT_NSEQ(([NSValue valueWithRange:{0, kTestStringLength}]),
               [ax_node AXVisibleCharacterRange]);
   EXPECT_EQ(0, [[ax_node AXInsertionPointLineNumber] intValue]);
 }
 
+class TestComboboxModel : public ui::ComboboxModel {
+ public:
+  TestComboboxModel() = default;
+
+  // ui::ComboboxModel:
+  int GetItemCount() const override { return 2; }
+  base::string16 GetItemAt(int index) override {
+    return index == 0 ? base::SysNSStringToUTF16(kTestStringValue)
+                      : base::ASCIIToUTF16("Second Item");
+  }
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(TestComboboxModel);
+};
+
+// Test a11y attributes of Comboboxes.
+TEST_F(NativeWidgetMacAccessibilityTest, Combobox) {
+  Combobox* combobox = new Combobox(base::MakeUnique<TestComboboxModel>());
+  combobox->SetSize(GetWidgetBounds().size());
+  widget()->GetContentsView()->AddChildView(combobox);
+
+  id ax_node = A11yElementAtMidpoint();
+  EXPECT_TRUE(ax_node);
+
+  EXPECT_NSEQ(NSAccessibilityPopUpButtonRole, [ax_node AXRole]);
+
+  // The initial value should be the first item in the menu.
+  EXPECT_NSEQ(kTestStringValue, [ax_node AXValue]);
+  combobox->SetSelectedIndex(1);
+  EXPECT_NSEQ(@"Second Item", [ax_node AXValue]);
+
+  // Expect to see both a press action and a show menu action. This matches
+  // Cocoa behavior.
+  EXPECT_NSEQ((@[ NSAccessibilityPressAction, NSAccessibilityShowMenuAction ]),
+              [ax_node accessibilityActionNames]);
+}
+
 }  // namespace views