bug 431615 - HTML 4.01 MAP element prevents links from displaying using a screen reader, patch by Alexander Surkov <surkov.alexander@gmail.com>, r=me, r=aaronlev, sr=jst

accessible/src/base/nsAccessibilityService.cpp

@@ -1328,15 +1328,6 @@ NS_IMETHODIMP nsAccessibilityService::GetAccessible(nsIDOMNode *aNode,
   }
 #endif
 
-  nsCOMPtr<nsIContent> content(do_QueryInterface(aNode));
-  if (content && content->Tag() == nsAccessibilityAtoms::map) {
-    // Don't walk into maps, they take up no space.
-    // The nsHTMLAreaAccessible's they contain are attached as
-    // children of the appropriate nsHTMLImageAccessible.
-    *aIsHidden = PR_TRUE;
-    return NS_OK;
-  }
-
   // Check to see if we already have an accessible for this
   // node in the cache
   nsCOMPtr<nsIAccessNode> accessNode;
@@ -1351,6 +1342,8 @@ NS_IMETHODIMP nsAccessibilityService::GetAccessible(nsIDOMNode *aNode,
     return NS_OK;
   }
 
+  nsCOMPtr<nsIContent> content(do_QueryInterface(aNode));
+
   // No cache entry, so we must create the accessible
   // Check to see if hidden first
   nsCOMPtr<nsIDocument> nodeIsDoc;
@@ -1461,6 +1454,27 @@ NS_IMETHODIMP nsAccessibilityService::GetAccessible(nsIDOMNode *aNode,
     return InitAccessible(newAcc, aAccessible, nsnull);
   }
 
+  PRBool isHTML = content->IsNodeOfType(nsINode::eHTML);
+  if (isHTML && content->Tag() == nsAccessibilityAtoms::map) {
+    // Create hyper text accessible for HTML map if it is used to group links
+    // (see http://www.w3.org/TR/WCAG10-HTML-TECHS/#group-bypass). If the HTML
+    // map doesn't have 'name' attribute (or has empty name attribute) then we
+    // suppose it is used for links grouping. Otherwise we think it is used in
+    // conjuction with HTML image element and in this case we don't create any
+    // accessible for it and don't walk into it. The accessibles for HTML area
+    // (nsHTMLAreaAccessible) the map contains are attached as children of the
+    // appropriate accessible for HTML image (nsHTMLImageAccessible).
+    nsAutoString name;
+    content->GetAttr(kNameSpaceID_None, nsAccessibilityAtoms::name, name);
+    if (!name.IsEmpty()) {
+      *aIsHidden = PR_TRUE;
+      return NS_OK;
+    }
+    
+    nsresult rv = CreateHyperTextAccessible(frame, getter_AddRefs(newAcc));
+    NS_ENSURE_SUCCESS(rv, rv);
+  }
+
   nsRoleMapEntry *roleMapEntry = nsAccUtils::GetRoleMapEntry(aNode);
   if (roleMapEntry && !nsCRT::strcmp(roleMapEntry->roleString, "presentation") &&
       !content->IsFocusable()) { // For presentation only
@@ -1474,8 +1488,7 @@ NS_IMETHODIMP nsAccessibilityService::GetAccessible(nsIDOMNode *aNode,
   // say what kind of accessible to create.
   nsresult rv = GetAccessibleByType(aNode, getter_AddRefs(newAcc));
   NS_ENSURE_SUCCESS(rv, rv);
-  
-  PRBool isHTML = content->IsNodeOfType(nsINode::eHTML);
+
   if (!newAcc && !isHTML) {
     if (content->GetNameSpaceID() == kNameSpaceID_SVG &&
              content->Tag() == nsAccessibilityAtoms::svg) {

accessible/tests/mochitest/test_nsIAccessibleHyperLink.html

@@ -255,6 +255,15 @@ https://bugzilla.mozilla.org/show_bug.cgi?id=418368
                  (state_selectable),
                  (ext_state_horizontal), (state_focusable | state_linked));
 
+      //////////////////////////////////////////////////////////////////////////
+      // Maps to group links (bug 431615).
+      var linksMapElement = document.getElementById("linksmap");
+      var linksMapAcc;
+      try {
+        linksMapAcc = accService.getAccessibleFor(linksMapElement);
+      } catch(e) { }
+    
+      ok(linksMapAcc, "no accessible for map grouping links!");
       SimpleTest.finish();
     }
 
@@ -299,5 +308,15 @@ https://bugzilla.mozilla.org/show_bug.cgi?id=418368
   <a id="LinkWithSpan" href="http://www.heise.de/"><span lang="de">Heise Online</span></a>
   <br>Named anchor, must not have "linked" state for it to be exposed correctly:<br>
   <a id="namedAnchor" name="named_anchor">This should never be of state_linked</a>
+
+  <br>Map that is used to group links (www.w3.org/TR/WCAG10-HTML-TECHS/#group-bypass),
+   also see the bug 431615:<br>
+  <map id="linksmap" title="Site navigation">
+    <ul>
+      <li><a href="http://mozilla.org">About the project</a></li>
+      <li><a href="http://mozilla.org">Sites and sounds</a></li>
+    </ul>
+  </map>
+
 </body>
 </html>