Try harder to return accessible names

Always check if there is another accessible set as title for the one
queried. For text fields also return the placeholder property if nothing
else is set.

Change-Id: I3f10ff04338a405ad8de00e75e15dded4aaeed3b
Reviewed-by: Jocelyn Turcotte <jocelyn.turcotte@digia.com>

1 files changed, 81 insertions, 1 deletions

diff --git a/src/core/browser_accessibility_qt.cpp b/src/core/browser_accessibility_qt.cpp
index d2710b0ea..405bafb94 100644
--- a/src/core/browser_accessibility_qt.cpp
+++ b/src/core/browser_accessibility_qt.cpp
@@ -34,6 +34,10 @@
 **
 ****************************************************************************/
 
+// 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 "browser_accessibility_qt.h"
 
 #include "third_party/WebKit/public/web/WebAXEnums.h"
@@ -52,6 +56,82 @@ BrowserAccessibilityQt::BrowserAccessibilityQt()
     QAccessible::registerAccessibleInterface(this);
 }
 
+// This function is taken from chromium/content/browser/accessibility/browser_accessibility_win.cc
+// see also http://www.w3.org/TR/html-aapi
+void BrowserAccessibilityQt::OnDataChanged()
+{
+    BrowserAccessibility::OnDataChanged();
+
+    // The calculation of the accessible name of an element has been
+    // standardized in the HTML to Platform Accessibility APIs Implementation
+    // Guide (http://www.w3.org/TR/html-aapi/). In order to return the
+    // appropriate accessible name on Windows, we need to apply some logic
+    // to the fields we get from WebKit.
+    //
+    // TODO(dmazzoni): move most of this logic into WebKit.
+    //
+    // WebKit gives us:
+    //
+    //   name: the default name, e.g. inner text
+    //   title ui element: a reference to a <label> element on the same
+    //       page that labels this node.
+    //   description: accessible labels that override the default name:
+    //       aria-label or aria-labelledby or aria-describedby
+    //   help: the value of the "title" attribute
+    //
+    // On Windows, the logic we apply lets some fields take precedence and
+    // always returns the primary name in "name" and the secondary name,
+    // if any, in "description".
+
+    int title_elem_id = GetIntAttribute(
+                ui::AX_ATTR_TITLE_UI_ELEMENT);
+    std::string help = GetStringAttribute(ui::AX_ATTR_HELP);
+    std::string description = GetStringAttribute(
+                ui::AX_ATTR_DESCRIPTION);
+
+    // WebKit annoyingly puts the title in the description if there's no other
+    // description, which just confuses the rest of the logic. Put it back.
+    // Now "help" is always the value of the "title" attribute, if present.
+    std::string title_attr;
+    if (GetHtmlAttribute("title", &title_attr) &&
+            description == title_attr &&
+            help.empty()) {
+        help = description;
+        description.clear();
+    }
+
+    // Now implement the main logic: the descripion should become the name if
+    // it's nonempty, and the help should become the description if
+    // there's no description - or the name if there's no name or description.
+    if (!description.empty()) {
+        set_name(description);
+        description.clear();
+    }
+    if (!help.empty() && description.empty()) {
+        description = help;
+        help.clear();
+    }
+    if (!description.empty() && name().empty() && !title_elem_id) {
+        set_name(description);
+        description.clear();
+    }
+
+    // If it's a text field, also consider the placeholder.
+    std::string placeholder;
+    if (GetRole() == ui::AX_ROLE_TEXT_FIELD &&
+            HasState(ui::AX_STATE_FOCUSABLE) &&
+            GetHtmlAttribute("placeholder", &placeholder)) {
+        if (name().empty() && !title_elem_id) {
+            set_name(placeholder);
+        } else if (description.empty()) {
+            description = placeholder;
+        }
+    }
+
+    SetStringAttribute(ui::AX_ATTR_DESCRIPTION, description);
+    SetStringAttribute(ui::AX_ATTR_HELP, help);
+}
+
 bool BrowserAccessibilityQt::isValid() const
 {
     return true;
@@ -128,7 +208,7 @@ QString BrowserAccessibilityQt::text(QAccessible::Text t) const
 {
     switch (t) {
     case QAccessible::Name:
-        return toQt(GetStringAttribute(ui::AX_ATTR_NAME));
+        return toQt(name());
     case QAccessible::Description:
         return toQt(GetStringAttribute(ui::AX_ATTR_DESCRIPTION));
     case QAccessible::Help: