Bug 1624729 - Introduce nsIAccessibleMacInterface as mac native xpc interface. r=yzen,morgan

Differential Revision: https://phabricator.services.mozilla.com/D68123

--HG--
extra : moz-landing-system : lando

accessible/interfaces/moz.build

@@ -7,6 +7,9 @@
 if CONFIG['MOZ_WIDGET_TOOLKIT'] == 'windows' and CONFIG['COMPILE_ENVIRONMENT']:
     DIRS += ['gecko', 'msaa', 'ia2']
 
+if CONFIG['MOZ_WIDGET_TOOLKIT'] == 'cocoa':
+    XPIDL_SOURCES += ['nsIAccessibleMacInterface.idl']
+
 XPIDL_SOURCES += [
     'nsIAccessibilityService.idl',
     'nsIAccessible.idl',

accessible/interfaces/nsIAccessibleMacInterface.idl

@@ -0,0 +1,40 @@
+/* -*- Mode: C; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsISupports.idl"
+
+%{C++
+#define NS_ACCESSIBLE_MAC_EVENT_TOPIC "accessible-mac-event"
+%}
+
+[scriptable, builtinclass, uuid(9d27cf21-66fc-47dc-8a07-98edb18707b1)]
+interface nsIAccessibleMacInterface : nsISupports
+{
+  /**
+   * List of available attribute names for tthe object.
+   * Emulates `AXUIElementCopyAttributeNames`.
+   */
+  readonly attribute Array<AString> attributeNames;
+
+  /**
+   * List of available action names for tthe object.
+   * Emulates `AXUIElementCopyActionNames`.
+   */
+  readonly attribute Array<AString> actionNames;
+
+  /**
+   * Returns the value of an attribute.
+   * Emulates `AXUIElementCopyAttributeValue`.
+   */
+  [implicit_jscontext]
+  jsval getAttributeValue(in AString attributeName);
+
+  /**
+   * Requests that the accessibility object perform the specified action.
+   * Emulatets `AXUIElementPerformAction`.
+   */
+  void performAction(in AString actionName);
+};
+

accessible/mac/AccessibleWrap.h

@@ -53,6 +53,8 @@ class AccessibleWrap : public Accessible {
   virtual nsresult HandleAccEvent(AccEvent* aEvent) override;
 
  protected:
+  friend class xpcAccessibleMacInterface;
+
   /**
    * Return true if the parent doesn't have children to expose to AT.
    */

accessible/xpcom/moz.build

@@ -45,8 +45,13 @@ elif CONFIG['MOZ_WIDGET_TOOLKIT'] == 'windows':
     ]
 elif CONFIG['MOZ_WIDGET_TOOLKIT'] == 'cocoa':
     LOCAL_INCLUDES += [
+        '/accessible/ipc',
+        '/accessible/ipc/other',
         '/accessible/mac',
     ]
+    UNIFIED_SOURCES += [
+        'xpcAccessibleMacInterface.mm'
+    ]
 elif CONFIG['MOZ_WIDGET_TOOLKIT'] == 'android':
     LOCAL_INCLUDES += [
         '/accessible/android',

accessible/xpcom/xpcAccessible.cpp

@@ -18,6 +18,10 @@
 #include "nsIMutableArray.h"
 #include "nsPersistentProperties.h"
 
+#ifdef MOZ_WIDGET_COCOA
+#  include "xpcAccessibleMacInterface.h"
+#endif
+
 using namespace mozilla::a11y;
 
 NS_IMETHODIMP
@@ -385,7 +389,19 @@ xpcAccessible::GetAttributes(nsIPersistentProperties** aAttributes) {
 
 NS_IMETHODIMP
 xpcAccessible::GetNativeInterface(nsISupports** aNativeInterface) {
+#ifdef MOZ_WIDGET_COCOA
+  NS_ENSURE_ARG_POINTER(aNativeInterface);
+
+  // We don't cache or store this instance anywhere so each get returns a
+  // different instance. So `acc.nativeInterface != acc.nativeInterface`. This
+  // just seems simpler and more robust for now.
+  nsCOMPtr<nsISupports> macIface = new xpcAccessibleMacInterface(IntlGeneric());
+  macIface.swap(*aNativeInterface);
+
+  return NS_OK;
+#else
   return NS_ERROR_NOT_IMPLEMENTED;
+#endif
 }
 
 NS_IMETHODIMP

accessible/xpcom/xpcAccessibleMacInterface.h

@@ -0,0 +1,46 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_a11y_xpcAccessibleMacInterface_h_
+#define mozilla_a11y_xpcAccessibleMacInterface_h_
+
+#include "nsIAccessibleMacInterface.h"
+
+#include "AccessibleOrProxy.h"
+
+class nsIAccessibleMacInterface;
+
+namespace mozilla {
+namespace a11y {
+
+class xpcAccessibleMacInterface : public nsIAccessibleMacInterface {
+ public:
+  // Construct an xpcAccessibleMacInterface using the native object
+  // associated with this accessible or proxy.
+  explicit xpcAccessibleMacInterface(AccessibleOrProxy aObj);
+
+  // Construct an xpcAccessibleMacInterface using this
+  // native object that conforms to the NSAccessibility protocol.
+  explicit xpcAccessibleMacInterface(id aNativeObj);
+
+  NS_DECL_ISUPPORTS
+  NS_DECL_NSIACCESSIBLEMACINTERFACE
+
+ protected:
+  virtual ~xpcAccessibleMacInterface();
+
+  id mNativeObject;
+
+ private:
+  xpcAccessibleMacInterface(const xpcAccessibleMacInterface&) = delete;
+  xpcAccessibleMacInterface& operator=(const xpcAccessibleMacInterface&) =
+      delete;
+};
+
+}  // namespace a11y
+}  // namespace mozilla
+
+#endif

accessible/xpcom/xpcAccessibleMacInterface.mm

@@ -0,0 +1,41 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "xpcAccessibleMacInterface.h"
+
+#import "mozAccessible.h"
+
+using namespace mozilla::a11y;
+
+NS_IMPL_ISUPPORTS(xpcAccessibleMacInterface, nsIAccessibleMacInterface)
+
+xpcAccessibleMacInterface::xpcAccessibleMacInterface(AccessibleOrProxy aObj) {
+  mNativeObject = aObj.IsProxy()
+                      ? GetNativeFromProxy(aObj.AsProxy())
+                      : static_cast<AccessibleWrap*>(aObj.AsAccessible())->GetNativeObject();
+  [mNativeObject retain];
+}
+
+xpcAccessibleMacInterface::xpcAccessibleMacInterface(id aNativeObj) : mNativeObject(aNativeObj) {
+  [mNativeObject retain];
+}
+
+xpcAccessibleMacInterface::~xpcAccessibleMacInterface() { [mNativeObject release]; }
+
+NS_IMETHODIMP
+xpcAccessibleMacInterface::GetAttributeNames(nsTArray<nsString>& aAttributeNames) { return NS_OK; }
+
+NS_IMETHODIMP
+xpcAccessibleMacInterface::GetActionNames(nsTArray<nsString>& aActionNames) { return NS_OK; }
+
+NS_IMETHODIMP
+xpcAccessibleMacInterface::PerformAction(const nsAString& aActionName) { return NS_OK; }
+
+NS_IMETHODIMP
+xpcAccessibleMacInterface::GetAttributeValue(const nsAString& aAttributeName, JSContext* aCx,
+                                             JS::MutableHandleValue aResult) {
+  return NS_OK;
+}