Fixed algorithms that compute bounding rectangles and word start offsets to take into account IA2 h…

content/browser/accessibility/browser_accessibility.cc

Index: content/browser/accessibility/browser_accessibility.cc
diff --git a/content/browser/accessibility/browser_accessibility.cc b/content/browser/accessibility/browser_accessibility.cc
index 9f528bd0de10cb7f8c7624574c6b619cce9a763e..73312dcc09dca2c2094b8842038b877a842ae04f 100644
--- a/content/browser/accessibility/browser_accessibility.cc
+++ b/content/browser/accessibility/browser_accessibility.cc
@@ -104,7 +104,7 @@ bool BrowserAccessibility::IsTextOnlyObject() const {
 
 BrowserAccessibility* BrowserAccessibility::PlatformGetChild(
     uint32_t child_index) const {
-  DCHECK(child_index < PlatformChildCount());
+  DCHECK_LT(child_index, PlatformChildCount());
   BrowserAccessibility* result = nullptr;
 
   if (HasIntAttribute(ui::AX_ATTR_CHILD_TREE_ID)) {
@@ -261,19 +261,25 @@ gfx::Rect BrowserAccessibility::GetGlobalBoundsRect() const {
 gfx::Rect BrowserAccessibility::GetLocalBoundsForRange(int start, int len)
     const {
   if (GetRole() != ui::AX_ROLE_STATIC_TEXT) {
-    // Apply recursively to all static text descendants. For example, if
-    // you call it on a div with two text node children, it just calls
-    // GetLocalBoundsForRange on each of the two children (adjusting
-    // |start| for each one) and unions the resulting rects.
     gfx::Rect bounds;
-    for (size_t i = 0; i < InternalChildCount(); ++i) {
+    for (size_t i = 0; i < InternalChildCount() && start >= 0; ++i) {
       BrowserAccessibility* child = InternalGetChild(i);
-      int child_len = child->GetInnerTextLength();
-      if (start < child_len && start + len > 0) {
-        gfx::Rect child_rect = child->GetLocalBoundsForRange(start, len);
+      // Embedded objects are of length one, since they are represented only by

[dmazzoni, 2016/01/20 01:10:43]

This comment confuses me. It talks about embedded objects, but the code checks
if the child is a text-only object, which is a static text or line break.

+      // a special character.
+      int child_length_in_parent =
+          child->IsTextOnlyObject() ? static_cast<int>(child->GetText().size())
+                                    : 1;
+      if (start < child_length_in_parent) {
+        gfx::Rect child_rect;
+        if (child->IsTextOnlyObject())
+          child_rect = child->GetLocalBoundsForRange(start, len);
+        else

[dmazzoni, 2016/01/20 01:10:43]

nit: Need braces around both blocks

+          child_rect = child->GetLocalBoundsForRange(
+              start, static_cast<int>(child->GetText().size()));
         bounds.Union(child_rect);
+        len -= child_length_in_parent;
       }
-      start -= child_len;
+      start -= child_length_in_parent;
     }
     return ElementBoundsToLocalBounds(bounds);
   }
@@ -291,9 +297,7 @@ gfx::Rect BrowserAccessibility::GetLocalBoundsForRange(int start, int len)
       continue;
     }
 
-    std::string child_text;
-    child->GetStringAttribute(ui::AX_ATTR_NAME, &child_text);
-    int child_len = static_cast<int>(child_text.size());
+    int child_len = static_cast<int>(GetText().size());
     child_start = child_end;
     child_end += child_len;
 
@@ -382,7 +386,7 @@ int BrowserAccessibility::GetWordStartBoundary(
     int start, ui::TextBoundaryDirection direction) const {
   DCHECK_GE(start, -1);
   // Special offset that indicates that a word boundary has not been found.
-  int word_start_not_found = GetInnerTextLength();
+  int word_start_not_found = static_cast<int>(GetText().size());
   int word_start = word_start_not_found;
 
   switch (GetRole()) {
@@ -397,9 +401,7 @@ int BrowserAccessibility::GetWordStartBoundary(
         child_start = child_end;
         BrowserAccessibility* child = InternalGetChild(i);
         DCHECK_EQ(child->GetRole(), ui::AX_ROLE_INLINE_TEXT_BOX);
-        const std::string& child_text = child->GetStringAttribute(
-            ui::AX_ATTR_NAME);
-        int child_len = static_cast<int>(child_text.size());
+        int child_len = static_cast<int>(GetText().size());
         child_end += child_len; // End is one past the last character.
 
         const std::vector<int32_t>& word_starts =
@@ -455,19 +457,23 @@ int BrowserAccessibility::GetWordStartBoundary(
       int child_start = 0;
       for (size_t i = 0; i < InternalChildCount(); ++i) {
         BrowserAccessibility* child = InternalGetChild(i);
-        int child_len = child->GetInnerTextLength();
-        int child_word_start = child->GetWordStartBoundary(start, direction);
-        if (child_word_start < child_len) {
-          // We have found a possible word boundary.
-          word_start = child_start + child_word_start;
-        }
+        // An embedded object is always represented by a single special
+        // character.
+        int child_len = 1;
+        if (child->IsTextOnlyObject()) {
+          child_len = static_cast<int>(child->GetText().size());
+          int child_word_start = child->GetWordStartBoundary(start, direction);
+          if (child_word_start < child_len) {
+            // We have found a possible word boundary.
+            word_start = child_start + child_word_start;
+          }
 
-        // Decide when to stop searching.
-        if ((word_start != word_start_not_found &&
-            direction == ui::FORWARDS_DIRECTION) ||
-            (start < child_len &&
-            direction == ui::BACKWARDS_DIRECTION)) {
-          break;
+          // Decide when to stop searching.
+          if ((word_start != word_start_not_found &&
+               direction == ui::FORWARDS_DIRECTION) ||
+              (start < child_len && direction == ui::BACKWARDS_DIRECTION)) {
+            break;
+          }
         }
 
         child_start += child_len;
@@ -656,7 +662,7 @@ bool BrowserAccessibility::GetAriaTristate(
   if (base::EqualsASCII(value, "mixed"))
     *is_mixed = true;
 
-  return false;  // Not set
+  return false;  // Not set.
 }
 
 bool BrowserAccessibility::HasState(ui::AXState state_enum) const {
@@ -670,7 +676,8 @@ bool BrowserAccessibility::IsCellOrTableHeaderRole() const {
 }
 
 bool BrowserAccessibility::HasCaret() const {
-  if (IsEditableText() && !HasState(ui::AX_STATE_RICHLY_EDITABLE) &&
+  if (HasState(ui::AX_STATE_EDITABLE) &&
+      !HasState(ui::AX_STATE_RICHLY_EDITABLE) &&
       HasIntAttribute(ui::AX_ATTR_TEXT_SEL_START) &&
       HasIntAttribute(ui::AX_ATTR_TEXT_SEL_END)) {
     return true;
@@ -688,10 +695,6 @@ bool BrowserAccessibility::HasCaret() const {
   return true;
 }
 
-bool BrowserAccessibility::IsEditableText() const {
-  return HasState(ui::AX_STATE_EDITABLE);
-}
-
 bool BrowserAccessibility::IsWebAreaForPresentationalIframe() const {
   if (GetRole() != ui::AX_ROLE_WEB_AREA &&
       GetRole() != ui::AX_ROLE_ROOT_WEB_AREA) {
@@ -792,10 +795,6 @@ base::string16 BrowserAccessibility::GetInnerText() const {
   return text;
 }
 
-int BrowserAccessibility::GetInnerTextLength() const {
-  return static_cast<int>(GetInnerText().size());
-}
-
 void BrowserAccessibility::FixEmptyBounds(gfx::Rect* bounds) const
 {
   if (bounds->width() > 0 && bounds->height() > 0)