Bug 395909. Should not require namespaces for ARIA role usage in text/html. r=surkov, a=dsicore

accessible/public/nsIAccessibilityService.idl

@@ -55,7 +55,7 @@ interface nsIAccessibilityService : nsIAccessibleRetrieval
   nsIAccessible createHyperTextAccessible(in nsISupports aFrame);
   nsIAccessible createHTMLBRAccessible(in nsISupports aFrame);
   nsIAccessible createHTMLButtonAccessible(in nsISupports aFrame);
-  nsIAccessible createHTMLAccessibleByMarkup(in nsIFrame aFrame, in nsIWeakReference aWeakShell, in nsIDOMNode aDOMNode, in AString aRole);
+  nsIAccessible createHTMLAccessibleByMarkup(in nsIFrame aFrame, in nsIWeakReference aWeakShell, in nsIDOMNode aDOMNode);
   nsIAccessible createHTMLLIAccessible(in nsISupports aFrame, in nsISupports aBulletFrame, in AString aBulletText);
   nsIAccessible createHTMLCheckboxAccessible(in nsISupports aFrame);
   nsIAccessible createHTMLComboboxAccessible(in nsIDOMNode aNode, in nsIWeakReference aPresShell);

accessible/src/base/nsAccessNode.cpp

@@ -47,12 +47,14 @@
 #include "nsIDocShellTreeItem.h"
 #include "nsIDocument.h"
 #include "nsIDocumentViewer.h"
+#include "nsIDOM3Node.h"
 #include "nsIDOMCSSStyleDeclaration.h"
 #include "nsIDOMCSSPrimitiveValue.h"
 #include "nsIDOMDocument.h"
 #include "nsIDOMElement.h"
 #include "nsIDOMHTMLDocument.h"
 #include "nsIDOMHTMLElement.h"
+#include "nsIDOMNSDocument.h"
 #include "nsIDOMNSHTMLElement.h"
 #include "nsIDOMViewCSS.h"
 #include "nsIDOMWindow.h"
@@ -890,3 +892,71 @@ nsAccessNode::GetLanguage(nsAString& aLanguage)
   return NS_OK;
 }
 
+PRBool
+nsAccessNode::GetARIARole(nsIContent *aContent, nsString& aRole)
+{
+  nsAutoString prefix;
+  PRBool strictPrefixChecking = PR_TRUE;
+  aRole.Truncate();
+
+  if (aContent->IsNodeOfType(nsINode::eHTML)) { // HTML node
+    // Allow non-namespaced role attribute in HTML
+    aContent->GetAttr(kNameSpaceID_None, nsAccessibilityAtoms::role, aRole);
+    // Find non-namespaced role attribute on HTML node
+    nsCOMPtr<nsIDOMNSDocument> doc(do_QueryInterface(aContent->GetDocument()));
+    if (doc) {
+      // In text/html we are hardcoded to allow the exact prefix "wairole:" to 
+      // always indicate that we are using the WAI roles.
+      // This allows ARIA to be used within text/html where namespaces cannot be defined.
+      // We also now relax the prefix checking, which means no prefix is required to use WAI Roles
+      nsAutoString mimeType;
+      doc->GetContentType(mimeType);
+      if (mimeType.EqualsLiteral("text/html")) {
+        prefix = NS_LITERAL_STRING("wairole:");
+        strictPrefixChecking = PR_FALSE;
+      }
+    }
+  }
+
+  // Try namespaced-role attribute (xhtml or xhtml2 namespace) -- allowed in any kind of content
+  if (aRole.IsEmpty() && !aContent->GetAttr(kNameSpaceID_XHTML, nsAccessibilityAtoms::role, aRole) &&
+      !aContent->GetAttr(kNameSpaceID_XHTML2_Unofficial, nsAccessibilityAtoms::role, aRole)) {
+    return PR_FALSE;
+  }
+
+  PRBool hasPrefix = (aRole.Find(":") >= 0);
+
+  if (!hasPrefix) {
+    // * No prefix* -- not a QName
+    // Just return entire string as long as prefix is not currently required
+    if (strictPrefixChecking) {
+      // Prefix was required and we didn't have one
+      aRole.Truncate();
+      return PR_FALSE;
+    }
+    return PR_TRUE;
+  }
+
+  // * Has prefix * -- is a QName (role="prefix:rolename")
+  if (strictPrefixChecking) {  // Not text/html, we need to actually find the WAIRole prefix
+    // QI to nsIDOM3Node causes some overhead. Unfortunately we need to do this each
+    // time there is a prefixed role attribute, because the prefix to namespace mappings
+    // can change within any subtree via the xmlns attribute
+    nsCOMPtr<nsIDOM3Node> dom3Node(do_QueryInterface(aContent));
+    if (dom3Node) {
+      // Look up exact prefix name for WAI Roles
+      NS_NAMED_LITERAL_STRING(kWAIRoles_Namespace, "http://www.w3.org/2005/01/wai-rdf/GUIRoleTaxonomy#");
+      dom3Node->LookupPrefix(kWAIRoles_Namespace, prefix);
+      prefix += ':';
+    }
+  }
+
+  PRUint32 length = prefix.Length();
+  if (length > 1 && StringBeginsWith(aRole, prefix)) {
+    // Is a QName (role="prefix:rolename"), and prefix matches WAI Role prefix
+    // Trim the WAI Role prefix off
+    aRole.Cut(0, length);
+  }
+
+  return PR_TRUE;
+}

accessible/src/base/nsAccessNode.h

@@ -71,6 +71,16 @@ class nsApplicationAccessibleWrap;
 typedef nsInterfaceHashtable<nsVoidPtrHashKey, nsIAccessNode>
         nsAccessNodeHashtable;
 
+/**
+ * Does the current content have this ARIA role? 
+ * Implemented as a compiler macro so that length can be computed at compile time.
+ * @param aContent  Node to get role string from
+ * @param aRoleName Role string to compare with -- literal const char*
+ * @return PR_TRUE if there is a match
+ */
+#define ARIARoleEquals(aContent, aRoleName) \
+  nsAccessNode::ARIARoleEqualsImpl(aContent, aRoleName, NS_ARRAY_LENGTH(aRoleName) - 1)
+
 class nsAccessNode: public nsIAccessNode, public nsPIAccessNode
 {
   public: // construction, destruction
@@ -114,14 +124,16 @@ class nsAccessNode: public nsIAccessNode, public nsPIAccessNode
               aContent->HasAttr(kNameSpaceID_XHTML2_Unofficial, nsAccessibilityAtoms::role);
     }
 
-    // Return PR_TRUE if there is a role attribute, and fill it into aRole
-    static PRBool GetRoleAttribute(nsIContent *aContent, nsAString& aRole)
-    {
-      aRole.Truncate();
-      return (aContent->IsNodeOfType(nsINode::eHTML) && aContent->GetAttr(kNameSpaceID_None, nsAccessibilityAtoms::role, aRole)) ||
-              aContent->GetAttr(kNameSpaceID_XHTML, nsAccessibilityAtoms::role, aRole) ||
-              aContent->GetAttr(kNameSpaceID_XHTML2_Unofficial, nsAccessibilityAtoms::role, aRole);
-    }
+    /**
+     * Provide the role string if there is one
+     * @param aContent Node to get role string from
+     * @param aRole String to fill role into
+     * @return PR_TRUE if there is a role attribute, and fill it into aRole
+     */
+    static PRBool GetARIARole(nsIContent *aContent, nsString& aRole);
+
+    static PRBool ARIARoleEqualsImpl(nsIContent* aContent, const char* aRoleName, PRUint32 aLen)
+      { nsAutoString role; return GetARIARole(aContent, role) && role.EqualsASCII(aRoleName, aLen); }
 
     static void GetComputedStyleDeclaration(const nsAString& aPseudoElt,
                                             nsIDOMElement *aElement,

accessible/src/base/nsAccessibilityService.cpp

@@ -434,7 +434,6 @@ nsresult
 nsAccessibilityService::CreateHTMLAccessibleByMarkup(nsIFrame *aFrame,
                                                      nsIWeakReference *aWeakShell,
                                                      nsIDOMNode *aNode,
-                                                     const nsAString& aRole,
                                                      nsIAccessible **aAccessible)
 {
   // This method assumes we're in an HTML namespace.
@@ -1337,9 +1336,7 @@ NS_IMETHODIMP nsAccessibilityService::GetAccessible(nsIDOMNode *aNode,
   }
 
   nsAutoString role;
-  if (nsAccessNode::GetRoleAttribute(content, role) &&
-      StringEndsWith(role, NS_LITERAL_STRING(":presentation")) &&
-      !content->IsFocusable()) {
+  if (nsAccessNode::GetARIARole(content, role) && role.EqualsLiteral("presentation") && !content->IsFocusable()) {
     // Only create accessible for role=":presentation" if it is focusable --
     // in that case we need an accessible in case it gets focused, we
     // don't want focus ever to be 'lost'
@@ -1366,7 +1363,7 @@ NS_IMETHODIMP nsAccessibilityService::GetAccessible(nsIDOMNode *aNode,
   } else if (!newAcc) {  // HTML accessibles
     // Prefer to use markup (mostly tag name, perhaps attributes) to
     // decide if and what kind of accessible to create.
-    CreateHTMLAccessibleByMarkup(frame, aWeakShell, aNode, role, getter_AddRefs(newAcc));
+    CreateHTMLAccessibleByMarkup(frame, aWeakShell, aNode, getter_AddRefs(newAcc));
 
     PRBool tryFrame = (newAcc == nsnull);
     if (!content->IsFocusable()) { 

accessible/src/base/nsAccessible.cpp

@@ -45,7 +45,6 @@
 #include "nsIAccessibleHyperText.h"
 #include "nsAccessibleTreeWalker.h"
 
-#include "nsIDOM3Node.h"
 #include "nsIDOMElement.h"
 #include "nsIDOMDocument.h"
 #include "nsIDOMDocumentXBL.h"
@@ -53,7 +52,6 @@
 #include "nsIDOMHTMLDocument.h"
 #include "nsIDOMHTMLFormElement.h"
 #include "nsIDOMNodeFilter.h"
-#include "nsIDOMNSDocument.h"
 #include "nsIDOMNSHTMLElement.h"
 #include "nsIDOMTreeWalker.h"
 #include "nsIDOMXULButtonElement.h"
@@ -475,32 +473,7 @@ NS_IMETHODIMP nsAccessible::Init()
 {
   nsIContent *content = GetRoleContent(mDOMNode);
   nsAutoString roleString;
-  if (content && GetRoleAttribute(content, roleString)) {
-    // QI to nsIDOM3Node causes some overhead. Unfortunately we need to do this each
-    // time there is a role attribute, because the prefixe to namespace mappings
-    // can change within any subtree via the xmlns attribute
-    nsCOMPtr<nsIDOM3Node> dom3Node(do_QueryInterface(content));
-    if (dom3Node) {
-      nsAutoString prefix;
-      NS_NAMED_LITERAL_STRING(kWAIRoles_Namespace, "http://www.w3.org/2005/01/wai-rdf/GUIRoleTaxonomy#");
-      dom3Node->LookupPrefix(kWAIRoles_Namespace, prefix);
-      if (prefix.IsEmpty()) {
-        // In HTML we are hardcoded to allow the exact prefix "wairole:" to 
-        // always indicate that we are using the WAI roles. This allows DHTML accessibility
-        // to be used within HTML
-        nsCOMPtr<nsIDOMNSDocument> doc(do_QueryInterface(content->GetDocument()));
-        if (doc) {
-          nsAutoString mimeType;
-          doc->GetContentType(mimeType);
-          if (mimeType.EqualsLiteral("text/html")) {
-            prefix = NS_LITERAL_STRING("wairole");
-          }
-        }
-      }
-      prefix += ':';
-      PRUint32 length = prefix.Length();
-      if (length > 1 && StringBeginsWith(roleString, prefix)) {
-        roleString.Cut(0, length);
+  if (content && GetARIARole(content, roleString)) {
     nsCString utf8Role = NS_ConvertUTF16toUTF8(roleString); // For easy comparison
     ToLowerCase(utf8Role);
     PRUint32 index;
@@ -513,8 +486,6 @@ NS_IMETHODIMP nsAccessible::Init()
     // If no match, we use the last entry which maps to ROLE_NOTHING
     mRoleMapEntry = &nsARIAMap::gWAIRoleMap[index];
   }
-    }
-  }
 
   return nsAccessNodeWrap::Init();
 }
@@ -2067,7 +2038,7 @@ nsAccessible::GetAttributes(nsIPersistentProperties **aAttributes)
     // XXX In the future we may need to expose the dynamic content role inheritance chain
     // through this attribute
     nsAutoString xmlRole;
-    if (GetRoleAttribute(content, xmlRole)) {
+    if (GetARIARole(content, xmlRole)) {
       attributes->SetStringProperty(NS_LITERAL_CSTRING("xml-roles"), xmlRole, oldValueUnused);          
     }
 

accessible/src/base/nsDocAccessible.cpp

@@ -1807,9 +1807,7 @@ NS_IMETHODIMP nsDocAccessible::InvalidateCacheSubtree(nsIContent *aChild,
                             eCoalesceFromSameSubtree, isAsynch);
 
     // Check to see change occured in an ARIA menu, and fire an EVENT_MENUPOPUP_START if it did
-    nsAutoString role;
-    if (GetRoleAttribute(aChild, role) &&
-        StringEndsWith(role, NS_LITERAL_STRING(":menu"), nsCaseInsensitiveStringComparator())) {
+    if (ARIARoleEquals(aChild, "menu")) {
       FireDelayedToolkitEvent(nsIAccessibleEvent::EVENT_MENUPOPUP_START,
                               childNode, nsnull, eAllowDupes, isAsynch);
     }
@@ -1817,8 +1815,7 @@ NS_IMETHODIMP nsDocAccessible::InvalidateCacheSubtree(nsIContent *aChild,
     // Check to see if change occured inside an alert, and fire an EVENT_ALERT if it did
     nsIContent *ancestor = aChild;
     while (ancestor) {
-      if (GetRoleAttribute(ancestor, role) &&
-          StringEndsWith(role, NS_LITERAL_STRING(":alert"), nsCaseInsensitiveStringComparator())) {
+      if (ARIARoleEquals(ancestor, "alert")) {
         nsCOMPtr<nsIDOMNode> alertNode(do_QueryInterface(ancestor));
         FireDelayedToolkitEvent(nsIAccessibleEvent::EVENT_ALERT, alertNode, nsnull,
                                 eRemoveDupes, isAsynch);

accessible/src/msaa/nsAccessibleWrap.cpp

@@ -466,7 +466,7 @@ STDMETHODIMP nsAccessibleWrap::get_accRole(
 
   if (content->IsNodeOfType(nsINode::eELEMENT)) {
     nsAutoString roleString;
-    if (msaaRole != ROLE_SYSTEM_CLIENT && !GetRoleAttribute(content, roleString)) {
+    if (msaaRole != ROLE_SYSTEM_CLIENT && !GetARIARole(content, roleString)) {
       nsINodeInfo *nodeInfo = content->NodeInfo();
       nodeInfo->GetName(roleString);
       nsAutoString nameSpaceURI;