Fire AX text inserted event when embedded obj char changes.

See bug for details. This patch makes it so that we fire
the events  IA2_EVENT_TEXT_INSERTED and IA2_EVENT_TEXT_REMOVED
when the children referenced by the embedded object characters
changed, not just when the text changed.

This patch also avoids incorrectly firing these same two
events on a newly-created node.

BUG=425861

Review URL: https://codereview.chromium.org/859133003

Cr-Commit-Position: refs/heads/master@{#314280}

content/browser/accessibility/browser_accessibility.h

@@ -58,14 +58,8 @@ class CONTENT_EXPORT BrowserAccessibility {
   // its data changes.
   virtual void OnDataChanged() {}
 
-  // Called after an atomic update to the tree finished and this object
-  // was created or changed in this update.
-  virtual void OnUpdateFinished() {}
-
   virtual void OnSubtreeWillBeDeleted() {}
 
-  virtual void OnSubtreeCreationFinished() {}
-
   // Called when the location changed.
   virtual void OnLocationChanged() {}
 

content/browser/accessibility/browser_accessibility_manager.cc

@@ -433,15 +433,6 @@ void BrowserAccessibilityManager::OnNodeChanged(ui::AXNode* node) {
 void BrowserAccessibilityManager::OnAtomicUpdateFinished(
     bool root_changed,
     const std::vector<ui::AXTreeDelegate::Change>& changes) {
-  for (size_t i = 0; i < changes.size(); ++i) {
-    BrowserAccessibility* obj = GetFromAXNode(changes[i].node);
-    if (!obj)
-      continue;
-
-    obj->OnUpdateFinished();
-    if (changes[i].type == AXTreeDelegate::SUBTREE_CREATED)
-      GetFromAXNode(changes[i].node)->OnSubtreeCreationFinished();
-  }
 }
 
 BrowserAccessibilityDelegate*

content/browser/accessibility/browser_accessibility_manager_win.cc

@@ -306,17 +306,39 @@ void BrowserAccessibilityManagerWin::OnAtomicUpdateFinished(
     OnWindowFocused();
   }
 
-  // BrowserAccessibilityManager::OnAtomicUpdateFinished calls
-  // OnUpdateFinished() on each node in |changes|. However, the
-  // IAccessibleText text for a node is a concatenatenation of all of its child
-  // text nodes, so we can't compute a node's IAccessibleText in
-  // OnUpdateFinished because its children may not have been updated yet.
-  //
-  // So we make a second pass here to update IAccessibleText.
+  // Do a sequence of Windows-specific updates on each node. Each one is
+  // done in a single pass that must complete before the next step starts.
+  // The first step moves win_attributes_ to old_win_attributes_ and then
+  // recomputes all of win_attributes_ other than IAccessibleText.
   for (size_t i = 0; i < changes.size(); ++i) {
     BrowserAccessibility* obj = GetFromAXNode(changes[i].node);
-    if (obj && obj->IsNative())
-      obj->ToBrowserAccessibilityWin()->UpdateIAccessibleText();
+    if (obj && obj->IsNative() && !obj->PlatformIsChildOfLeaf())
+      obj->ToBrowserAccessibilityWin()->UpdateStep1ComputeWinAttributes();
+  }
+
+  // The next step updates the hypertext of each node, which is a
+  // concatenation of all of its child text nodes, so it can't run until
+  // the text of all of the nodes was computed in the previous step.
+  for (size_t i = 0; i < changes.size(); ++i) {
+    BrowserAccessibility* obj = GetFromAXNode(changes[i].node);
+    if (obj && obj->IsNative() && !obj->PlatformIsChildOfLeaf())
+      obj->ToBrowserAccessibilityWin()->UpdateStep2ComputeHypertext();
+  }
+
+  // The third step fires events on nodes based on what's changed - like
+  // if the name, value, or description changed, or if the hypertext had
+  // text inserted or removed. It's able to figure out exactly what changed
+  // because we still have old_win_attributes_ populated.
+  // This step has to run after the previous two steps complete because the
+  // client may walk the tree when it receives any of these events.
+  // At the end, it deletes old_win_attributes_ since they're not needed
+  // anymore.
+  for (size_t i = 0; i < changes.size(); ++i) {
+    BrowserAccessibility* obj = GetFromAXNode(changes[i].node);
+    if (obj && obj->IsNative() && !obj->PlatformIsChildOfLeaf()) {
+      obj->ToBrowserAccessibilityWin()->UpdateStep3FireEvents(
+          changes[i].type == AXTreeDelegate::SUBTREE_CREATED);
+    }
   }
 }
 

content/browser/accessibility/browser_accessibility_win.h

@@ -82,7 +82,7 @@ BrowserAccessibilityWin
   // Represents a non-static text node in IAccessibleHypertext. This character
   // is embedded in the response to IAccessibleText::get_text, indicating the
   // position where a non-static text child object appears.
-  CONTENT_EXPORT static const base::char16 kEmbeddedCharacter[];
+  CONTENT_EXPORT static const base::char16 kEmbeddedCharacter;
 
   // Mappings from roles and states to human readable strings. Initialize
   // with |InitializeStringMaps|.
@@ -97,15 +97,18 @@ BrowserAccessibilityWin
   // like NotifyWinEvent, and as the unique ID for IAccessible2 and ISimpleDOM.
   LONG unique_id_win() const { return unique_id_win_; }
 
-  CONTENT_EXPORT void UpdateIAccessibleText();
+  // Called after an atomic tree update completes. See
+  // BrowserAccessibilityManagerWin::OnAtomicUpdateFinished for more
+  // details on what these do.
+  CONTENT_EXPORT void UpdateStep1ComputeWinAttributes();
+  CONTENT_EXPORT void UpdateStep2ComputeHypertext();
+  CONTENT_EXPORT void UpdateStep3FireEvents(bool is_subtree_creation);
+  CONTENT_EXPORT void UpdateStep4DeleteOldWinAttributes();
 
   //
   // BrowserAccessibility methods.
   //
-  CONTENT_EXPORT virtual void OnDataChanged() override;
-  CONTENT_EXPORT virtual void OnUpdateFinished() override;
   CONTENT_EXPORT virtual void OnSubtreeWillBeDeleted() override;
-  CONTENT_EXPORT virtual void OnSubtreeCreationFinished() override;
   CONTENT_EXPORT virtual void NativeAddReference() override;
   CONTENT_EXPORT virtual void NativeReleaseReference() override;
   CONTENT_EXPORT virtual bool IsNative() const override;
@@ -791,6 +794,11 @@ BrowserAccessibilityWin
   base::string16 description() const { return win_attributes_->description; }
   base::string16 help() const { return win_attributes_->help; }
   base::string16 value() const { return win_attributes_->value; }
+  base::string16 hypertext() const { return win_attributes_->hypertext; }
+  std::map<int32, int32>& hyperlink_offset_to_index() const {
+    return win_attributes_->hyperlink_offset_to_index;
+  }
+  std::vector<int32>& hyperlinks() const { return win_attributes_->hyperlinks; }
 
  private:
   // Add one to the reference count and return the same object. Always
@@ -842,6 +850,7 @@ BrowserAccessibilityWin
   // be the name, it may be the value, etc. depending on the role.
   base::string16 TextForIAccessibleText();
 
+  bool IsSameHypertextCharacter(size_t old_char_index, size_t new_char_index);
   void ComputeHypertextRemovedAndInserted(
       int* start, int* old_len, int* new_len);
 
@@ -889,6 +898,16 @@ BrowserAccessibilityWin
 
     // IAccessible2 attributes.
     std::vector<base::string16> ia2_attributes;
+
+    // Hypertext.
+    base::string16 hypertext;
+
+    // Maps the |hypertext_| embedded character offset to an index in
+    // |hyperlinks_|.
+    std::map<int32, int32> hyperlink_offset_to_index;
+
+    // The id of a BrowserAccessibilityWin for each hyperlink.
+    std::vector<int32> hyperlinks;
   };
 
   scoped_ptr<WinAttributes> win_attributes_;
@@ -900,19 +919,6 @@ BrowserAccessibilityWin
   // Relationships between this node and other nodes.
   std::vector<BrowserAccessibilityRelation*> relations_;
 
-  // IAccessibleText text of this node including
-  // embedded hyperlink characters.
-  base::string16 old_hypertext_;
-  base::string16 hypertext_;
-
-  // Maps the |hypertext_| embedded character offset to an index in
-  // |hyperlinks_|.
-  std::map<int32, int32> hyperlink_offset_to_index_;
-
-  // Collection of non-static text child indicies, each of which corresponds to
-  // a hyperlink.
-  std::vector<int32> hyperlinks_;
-
   // The previous scroll position, so we can tell if this object scrolled.
   int previous_scroll_x_;
   int previous_scroll_y_;

content/browser/accessibility/browser_accessibility_win_unittest.cc

@@ -442,7 +442,7 @@ TEST_F(BrowserAccessibilityTest, TestSimpleHypertext) {
   CountedBrowserAccessibility::reset();
   scoped_ptr<BrowserAccessibilityManager> manager(
       BrowserAccessibilityManager::Create(
-          MakeAXTreeUpdate(root, root, text1, text2),
+          MakeAXTreeUpdate(root, text1, text2),
           NULL, new CountedBrowserAccessibilityFactory()));
   ASSERT_EQ(3, CountedBrowserAccessibility::num_instances());
 
@@ -547,7 +547,7 @@ TEST_F(BrowserAccessibilityTest, TestComplexHypertext) {
   base::win::ScopedBstr text;
   ASSERT_EQ(S_OK, root_obj->get_text(0, text_len, text.Receive()));
   const std::string embed = base::UTF16ToUTF8(
-      BrowserAccessibilityWin::kEmbeddedCharacter);
+      base::string16(1, BrowserAccessibilityWin::kEmbeddedCharacter));
   EXPECT_EQ(text1_name + embed + text2_name + embed,
             base::UTF16ToUTF8(base::string16(text)));
   text.Reset();

content/browser/accessibility/dump_accessibility_events_browsertest.cc

@@ -194,6 +194,11 @@ IN_PROC_BROWSER_TEST_F(DumpAccessibilityEventsTest,
   RunEventTest(FILE_PATH_LITERAL("description-change.html"));
 }
 
+IN_PROC_BROWSER_TEST_F(DumpAccessibilityEventsTest,
+                       AccessibilityEventsInnerHtmlChange) {
+  RunEventTest(FILE_PATH_LITERAL("inner-html-change.html"));
+}
+
 IN_PROC_BROWSER_TEST_F(DumpAccessibilityEventsTest,
                        AccessibilityEventsInputTypeTextValueChanged) {
   RunEventTest(FILE_PATH_LITERAL("input-type-text-value-changed.html"));

content/test/data/accessibility/event/add-child-expected-win.txt

-EVENT_OBJECT_SHOW on role=ROLE_SYSTEM_LISTITEM name="Item 3"
 IA2_EVENT_TEXT_INSERTED on role=ROLE_SYSTEM_LIST new_text={'<obj>' start=2 end=3}
+EVENT_OBJECT_SHOW on role=ROLE_SYSTEM_LISTITEM name="Item 3"
 EVENT_OBJECT_REORDER on role=ROLE_SYSTEM_LIST

content/test/data/accessibility/event/add-subtree-expected-win.txt

-EVENT_OBJECT_SHOW on role=ROLE_SYSTEM_LISTITEM name="Item 3"
 IA2_EVENT_TEXT_INSERTED on role=ROLE_SYSTEM_LIST new_text={'<obj>' start=2 end=3}
-IA2_EVENT_TEXT_INSERTED on role=ROLE_SYSTEM_LISTITEM name="Item 3" new_text={'<obj>Item 3' start=0 end=7}
+EVENT_OBJECT_SHOW on role=ROLE_SYSTEM_LISTITEM name="Item 3"
 EVENT_OBJECT_REORDER on role=ROLE_SYSTEM_LIST

content/test/data/accessibility/event/css-display-expected-win.txt

 EVENT_OBJECT_HIDE on role=div name="Heading"
+IA2_EVENT_TEXT_REMOVED on role=ROLE_SYSTEM_TOOLBAR old_text={'<obj>' start=0 end=1}
+IA2_EVENT_TEXT_INSERTED on role=ROLE_SYSTEM_TOOLBAR new_text={'<obj>' start=0 end=1}
 EVENT_OBJECT_SHOW on role=ROLE_SYSTEM_GROUPING name="Banner"
 EVENT_OBJECT_REORDER on role=ROLE_SYSTEM_TOOLBAR

content/test/data/accessibility/event/css-visibility-expected-win.txt

 EVENT_OBJECT_HIDE on role=div name="Heading"
+IA2_EVENT_TEXT_REMOVED on role=ROLE_SYSTEM_TOOLBAR old_text={'<obj>' start=0 end=1}
+IA2_EVENT_TEXT_INSERTED on role=ROLE_SYSTEM_TOOLBAR new_text={'<obj>' start=0 end=1}
 EVENT_OBJECT_SHOW on role=ROLE_SYSTEM_GROUPING name="Banner"
 EVENT_OBJECT_REORDER on role=ROLE_SYSTEM_TOOLBAR

content/test/data/accessibility/event/inner-html-change-expected-mac.txt

+#<skip -- need to generate>

content/test/data/accessibility/event/inner-html-change-expected-win.txt

+EVENT_OBJECT_HIDE on role=h1 name="A"
+EVENT_OBJECT_HIDE on role=P
+IA2_EVENT_TEXT_REMOVED on role=ROLE_SYSTEM_GROUPING old_text={'<obj><obj>' start=0 end=2}
+IA2_EVENT_TEXT_INSERTED on role=ROLE_SYSTEM_GROUPING new_text={'<obj><obj>' start=0 end=2}
+EVENT_OBJECT_SHOW on role=h1 name="C"
+EVENT_OBJECT_SHOW on role=P

content/test/data/accessibility/event/inner-html-change.html

+<!--
+The children changed / reorder event is fired an unpredictable number of times.
+@WIN-DENY:EVENT_OBJECT_REORDER*
+-->
+<!DOCTYPE html>
+<html>
+<body>
+<div role="group" id="main"><h1>A</h1><p>B</p></div>
+<script>
+  function go() {
+    document.querySelector('#main').innerHTML = '<h1>C</h1><p>D</p>';
+  }
+</script>
+</body>
+</html>

content/test/data/accessibility/event/remove-hidden-attribute-expected-win.txt

-EVENT_OBJECT_SHOW on role=ROLE_SYSTEM_LISTITEM name="Item 3"
 IA2_EVENT_TEXT_INSERTED on role=ROLE_SYSTEM_LIST new_text={'<obj>' start=2 end=3}
+EVENT_OBJECT_SHOW on role=ROLE_SYSTEM_LISTITEM name="Item 3"
 EVENT_OBJECT_REORDER on role=ROLE_SYSTEM_LIST

content/test/data/accessibility/event/remove-hidden-attribute-subtree-expected-win.txt

-EVENT_OBJECT_SHOW on role=ROLE_SYSTEM_LISTITEM name="Item 3"
 IA2_EVENT_TEXT_INSERTED on role=ROLE_SYSTEM_LIST new_text={'<obj>' start=2 end=3}
-IA2_EVENT_TEXT_INSERTED on role=ROLE_SYSTEM_LISTITEM name="Item 3" new_text={'<obj>Item 3' start=0 end=7}
+EVENT_OBJECT_SHOW on role=ROLE_SYSTEM_LISTITEM name="Item 3"
 EVENT_OBJECT_REORDER on role=ROLE_SYSTEM_LIST

content/test/data/accessibility/event/text-changed-expected-win.txt

 EVENT_OBJECT_HIDE on role=ROLE_SYSTEM_STATICTEXT name="Para"
-EVENT_OBJECT_SHOW on role=ROLE_SYSTEM_STATICTEXT name="Modified Para"
 IA2_EVENT_TEXT_INSERTED on role=P new_text={'Modified ' start=0 end=9}
+EVENT_OBJECT_SHOW on role=ROLE_SYSTEM_STATICTEXT name="Modified Para"
 EVENT_OBJECT_NAMECHANGE on role=ROLE_SYSTEM_STATICTEXT name="Modified Heading"
 IA2_EVENT_TEXT_INSERTED on role=h2 name="Heading" new_text={'Modified ' start=0 end=9}