Update browser cache of accessibility tree on renderer sub-tree changes....

chrome/browser/browser_accessibility_win_unittest.cc

 // Copyright (c) 2010 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 "base/scoped_ptr.h"
+#include "base/scoped_comptr_win.h"
 #include "chrome/browser/browser_accessibility_manager_win.h"
 #include "chrome/browser/browser_accessibility_win.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 using webkit_glue::WebAccessibility;
 
 // Subclass of BrowserAccessibility that counts the number of instances.
 class CountedBrowserAccessibility : public BrowserAccessibility {
  public:
   CountedBrowserAccessibility() { global_obj_count_++; }
   virtual ~CountedBrowserAccessibility() { global_obj_count_--; }
   static int global_obj_count_;
 };
 
 int CountedBrowserAccessibility::global_obj_count_ = 0;
 
 // Factory that creates a CountedBrowserAccessibility.
 class CountedBrowserAccessibilityFactory : public BrowserAccessibilityFactory {
  public:
   virtual ~CountedBrowserAccessibilityFactory() {}
   virtual BrowserAccessibility* Create() {
     CComObject<CountedBrowserAccessibility>* instance;
     HRESULT hr = CComObject<CountedBrowserAccessibility>::CreateInstance(
         &instance);
     DCHECK(SUCCEEDED(hr));
     return instance->NewReference();
   }
 };
 
+VARIANT CreateI4Variant(LONG value) {
+  VARIANT variant = {0};
+
+  V_VT(&variant) = VT_I4;
+  V_I4(&variant) = value;
+
+  return variant;
+}
+
+class BrowserAccessibilityTest : public testing::Test {
+ protected:
+  virtual void SetUp() {
+    // ATL needs a pointer to a COM module.
+    static CComModule module;
+    _pAtlModule = &module;
+
+    // Make sure COM is initialized for this thread; it's safe to call twice.
+    ::CoInitialize(NULL);
+  }
+
+  virtual void TearDown()
+  {
+    ::CoUninitialize();
+  }
+};
+
 // Test that BrowserAccessibilityManager correctly releases the tree of
 // BrowserAccessibility instances upon delete.
-TEST(BrowserAccessibilityTest, TestNoLeaks) {
-  // ATL needs a pointer to a COM module.
-  CComModule module;
-  _pAtlModule = &module;
-  // Make sure COM is initialized for this thread; it's safe to call twice.
-  ::CoInitialize(NULL);
-
+TEST_F(BrowserAccessibilityTest, TestNoLeaks) {
   // Create WebAccessibility objects for a simple document tree,
   // representing the accessibility information used to initialize
   // BrowserAccessibilityManager.
   WebAccessibility button;
   button.id = 2;
   button.name = L"Button";
   button.role = WebAccessibility::ROLE_BUTTON;
   button.state = 0;
 
   WebAccessibility checkbox;
@@ skipping 48 matching lines @@
   delete manager;
   ASSERT_EQ(2, CountedBrowserAccessibility::global_obj_count_);
 
   // Release each of our references and make sure that each one results in
   // the instance being deleted as its reference count hits zero.
   root_iaccessible->Release();
   ASSERT_EQ(1, CountedBrowserAccessibility::global_obj_count_);
   child1_iaccessible->Release();
   ASSERT_EQ(0, CountedBrowserAccessibility::global_obj_count_);
 }
+
+TEST_F(BrowserAccessibilityTest, TestChildrenChange) {
+  // Create WebAccessibility objects for a simple document tree,
+  // representing the accessibility information used to initialize
+  // BrowserAccessibilityManager.
+  WebAccessibility text;
+  text.id = 2;
+  text.role = WebAccessibility::ROLE_STATIC_TEXT;
+  text.value = L"old text";
+  text.state = 0;
+
+  WebAccessibility root;
+  root.id = 1;
+  root.name = L"Document";
+  root.role = WebAccessibility::ROLE_DOCUMENT;
+  root.state = 0;
+  root.children.push_back(text);
+
+  // Construct a BrowserAccessibilityManager with this WebAccessibility tree
+  // and a factory for an instance-counting BrowserAccessibility.
+  CountedBrowserAccessibility::global_obj_count_ = 0;
+  BrowserAccessibilityManager* manager =
+      new BrowserAccessibilityManager(
+          GetDesktopWindow(), root, NULL,
+          new CountedBrowserAccessibilityFactory());
+
+  // Query for the text IAccessible and verify that it returns "old text" as its
+  // value.
+  ScopedComPtr<IDispatch> text_dispatch;
+  HRESULT hr = manager->GetRoot()->get_accChild(CreateI4Variant(1),
+                                                text_dispatch.Receive());
+  ASSERT_EQ(S_OK, hr);
+
+  ScopedComPtr<IAccessible> text_accessible;
+  hr = text_dispatch.QueryInterface(text_accessible.Receive());
+  ASSERT_EQ(S_OK, hr);
+
+  CComBSTR value;
+  hr = text_accessible->get_accValue(CreateI4Variant(CHILDID_SELF), &value);
+  ASSERT_EQ(S_OK, hr);
+  EXPECT_STREQ(L"old text", value.m_str);
+
+  text_dispatch.Release();
+  text_accessible.Release();
+
+  // Notify the BrowserAccessibilityManager that the text child has changed.
+  text.value = L"new text";
+  std::vector<WebAccessibility> acc_changes;
+  acc_changes.push_back(text);
+  manager->OnAccessibilityObjectChildrenChange(acc_changes);
+
+  // Query for the text IAccessible and verify that it now returns "new text"
+  // as its value.
+  hr = manager->GetRoot()->get_accChild(
+      CreateI4Variant(1),
+      text_dispatch.Receive());
+  ASSERT_EQ(S_OK, hr);
+
+  hr = text_dispatch.QueryInterface(text_accessible.Receive());
+  ASSERT_EQ(S_OK, hr);
+
+  hr = text_accessible->get_accValue(CreateI4Variant(CHILDID_SELF), &value);
+  ASSERT_EQ(S_OK, hr);
+  EXPECT_STREQ(L"new text", value.m_str);
+
+  text_dispatch.Release();
+  text_accessible.Release();
+
+  // Delete the manager and test that all BrowserAccessibility instances are
+  // deleted.
+  delete manager;
+  ASSERT_EQ(0, CountedBrowserAccessibility::global_obj_count_);
+}
+
+TEST_F(BrowserAccessibilityTest, TestChildrenChangeNoLeaks) {
+  // Create WebAccessibility objects for a simple document tree,
+  // representing the accessibility information used to initialize
+  // BrowserAccessibilityManager.
+  WebAccessibility text;
+  text.id = 3;
+  text.role = WebAccessibility::ROLE_STATIC_TEXT;
+  text.state = 0;
+
+  WebAccessibility div;
+  div.id = 2;
+  div.role = WebAccessibility::ROLE_GROUP;
+  div.state = 0;
+
+  div.children.push_back(text);
+  text.id = 4;
+  div.children.push_back(text);
+
+  WebAccessibility root;
+  root.id = 1;
+  root.role = WebAccessibility::ROLE_DOCUMENT;
+  root.state = 0;
+  root.children.push_back(div);
+
+  // Construct a BrowserAccessibilityManager with this WebAccessibility tree
+  // and a factory for an instance-counting BrowserAccessibility and ensure
+  // that exactly 4 instances were created. Note that the manager takes
+  // ownership of the factory.
+  CountedBrowserAccessibility::global_obj_count_ = 0;
+  BrowserAccessibilityManager* manager =
+      new BrowserAccessibilityManager(
+          GetDesktopWindow(), root, NULL,
+          new CountedBrowserAccessibilityFactory());
+  ASSERT_EQ(4, CountedBrowserAccessibility::global_obj_count_);
+
+  // Notify the BrowserAccessibilityManager that the div node and its children
+  // were removed and ensure that only one BrowserAccessibility instance exists.
+  root.children.clear();
+  std::vector<WebAccessibility> acc_changes;
+  acc_changes.push_back(root);
+  manager->OnAccessibilityObjectChildrenChange(acc_changes);
+  ASSERT_EQ(1, CountedBrowserAccessibility::global_obj_count_);
+
+  // Delete the manager and test that all BrowserAccessibility instances are
+  // deleted.
+  delete manager;
+  ASSERT_EQ(0, CountedBrowserAccessibility::global_obj_count_);
+}