Fixed IAccessibleText::TextAtOffset with IA2_TEXT_BOUNDARY_WORD to return text that spans from the …

content/browser/accessibility/browser_accessibility_win.cc

 // Copyright (c) 2012 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 "content/browser/accessibility/browser_accessibility_win.h"
 
 #include <UIAutomationClient.h>
 #include <UIAutomationCoreApi.h>
 
 #include "base/strings/string_number_conversions.h"
@@ skipping 2073 matching lines @@
     enum IA2TextBoundaryType boundary_type,
     LONG* start_offset,
     LONG* end_offset,
     BSTR* text) {
   if (!instance_active())
     return E_FAIL;
 
   if (!start_offset || !end_offset || !text)
     return E_INVALIDARG;
 
+  const base::string16& text_str = TextForIAccessibleText();
+  HandleSpecialTextOffset(text_str, &offset);
+  if (offset < 0)
+    return E_INVALIDARG;
+
+  LONG text_len = text_str.length();
+  if (offset > text_len)
+    return E_INVALIDARG;
+
   // The IAccessible2 spec says we don't have to implement the "sentence"
   // boundary type, we can just let the screenreader handle it.
   if (boundary_type == IA2_TEXT_BOUNDARY_SENTENCE) {
     *start_offset = 0;
     *end_offset = 0;
     *text = NULL;
     return S_FALSE;
   }
 
-  const base::string16& text_str = TextForIAccessibleText();
+  // According to the IA2 Spec, only line boundaries should succeed when
+  // the offset is one past the end of the text.
+  if (offset == text_len && boundary_type != IA2_TEXT_BOUNDARY_LINE) {
+    *start_offset = 0;
+    *end_offset = 0;
+    *text = nullptr;
+    return S_FALSE;
+  }
 
   *start_offset = FindBoundary(
       text_str, boundary_type, offset, ui::BACKWARDS_DIRECTION);
   *end_offset = FindBoundary(
       text_str, boundary_type, offset, ui::FORWARDS_DIRECTION);
   return get_text(*start_offset, *end_offset, text);
 }
 
 STDMETHODIMP BrowserAccessibilityWin::get_textBeforeOffset(
     LONG offset,
@@ skipping 1439 matching lines @@
   }
   return ui::CHAR_BOUNDARY;
 }
 
 LONG BrowserAccessibilityWin::FindBoundary(
     const base::string16& text,
     IA2TextBoundaryType ia2_boundary,
     LONG start_offset,
     ui::TextBoundaryDirection direction) {
   HandleSpecialTextOffset(text, &start_offset);
+  if (ia2_boundary == IA2_TEXT_BOUNDARY_WORD &&
+      GetRole() == ui::AX_ROLE_TEXT_FIELD) {
+    return GetWordStartBoundary(static_cast<int>(start_offset), direction);
+  }
+
   ui::TextBoundaryType boundary = IA2TextBoundaryToTextBoundary(ia2_boundary);
   const std::vector<int32>& line_breaks = GetIntListAttribute(
       ui::AX_ATTR_LINE_BREAKS);
   return ui::FindAccessibleTextBoundary(
       text, line_breaks, boundary, start_offset, direction);
 }
 
 BrowserAccessibilityWin* BrowserAccessibilityWin::GetFromID(int32 id) {
   return manager()->GetFromID(id)->ToBrowserAccessibilityWin();
 }
@@ skipping 538 matching lines @@
     ia2_role = ia_role;
 
   win_attributes_->ia_role = ia_role;
   win_attributes_->ia_state = ia_state;
   win_attributes_->role_name = role_name;
   win_attributes_->ia2_role = ia2_role;
   win_attributes_->ia2_state = ia2_state;
 }
 
 }  // namespace content