Bug 573469 - part1, add iterator for IDRefs elements, r=fherrera, sr=neil, a=blockingFinal+

accessible/src/base/nsCoreUtils.cpp

@@ -47,7 +47,6 @@
 #include "nsIDOM3Node.h"
 #include "nsIDOMDocument.h"
 #include "nsIDOMDocumentView.h"
-#include "nsIDOMDocumentXBL.h"
 #include "nsIDOMHTMLDocument.h"
 #include "nsIDOMHTMLElement.h"
 #include "nsIDOMNodeList.h"
@@ -805,67 +804,6 @@ nsCoreUtils::GetLanguageFor(nsIContent *aContent, nsIContent *aRootContent,
     walkUp = walkUp->GetParent();
 }
 
-void
-nsCoreUtils::GetElementsByIDRefsAttr(nsIContent *aContent, nsIAtom *aAttr,
-                                     nsIArray **aRefElements)
-{
-  *aRefElements = nsnull;
-
-  nsAutoString ids;
-  if (!aContent->GetAttr(kNameSpaceID_None, aAttr, ids))
-    return;
-
-  ids.CompressWhitespace(PR_TRUE, PR_TRUE);
-
-  nsCOMPtr<nsIDOMDocument> document = do_QueryInterface(aContent->GetOwnerDoc());
-  NS_ASSERTION(document, "The given node is not in document!");
-  if (!document)
-    return;
-
-  nsCOMPtr<nsIDOMDocumentXBL> xblDocument;
-  if (aContent->IsInAnonymousSubtree())
-    xblDocument = do_QueryInterface(document);
-
-  nsCOMPtr<nsIMutableArray> refElms = do_CreateInstance(NS_ARRAY_CONTRACTID);
-
-  while (!ids.IsEmpty()) {
-    nsAutoString id;
-    PRInt32 idLength = ids.FindChar(' ');
-    NS_ASSERTION(idLength != 0,
-                 "Should not be 0 because of CompressWhitespace() call above");
-
-    if (idLength == kNotFound) {
-      id = ids;
-      ids.Truncate();
-    } else {
-      id = Substring(ids, 0, idLength);
-      ids.Cut(0, idLength + 1);
-    }
-
-    // If content is anonymous subtree then use "anonid" attribute to get
-    // elements, otherwise search elements in DOM by ID attribute.
-    nsCOMPtr<nsIDOMElement> refElement;
-    if (xblDocument) {
-      nsCOMPtr<nsIDOMElement> elm =
-        do_QueryInterface(aContent->GetBindingParent());
-      xblDocument->GetAnonymousElementByAttribute(elm,
-                                                  NS_LITERAL_STRING("anonid"),
-                                                  id,
-                                                  getter_AddRefs(refElement));
-    } else {
-      document->GetElementById(id, getter_AddRefs(refElement));
-    }
-
-    if (!refElement)
-      continue;
-
-    refElms->AppendElement(refElement, PR_FALSE);
-  }
-
-  NS_ADDREF(*aRefElements = refElms);
-  return;
-}
-
 void
 nsCoreUtils::GetElementsHavingIDRefsAttr(nsIContent *aRootContent,
                                          nsIContent *aContent,
@@ -1165,3 +1103,74 @@ nsAccessibleDOMStringList::Contains(const nsAString& aString, PRBool *aResult)
 
   return NS_OK;
 }
+
+
+////////////////////////////////////////////////////////////////////////////////
+// IDRefsIterator
+////////////////////////////////////////////////////////////////////////////////
+
+IDRefsIterator::IDRefsIterator(nsIContent* aContent, nsIAtom* aIDRefsAttr) :
+  mCurrIdx(0)
+{
+  if (!aContent->IsInDoc() ||
+      !aContent->GetAttr(kNameSpaceID_None, aIDRefsAttr, mIDs))
+    return;
+
+  if (aContent->IsInAnonymousSubtree()) {
+    mXBLDocument = do_QueryInterface(aContent->GetOwnerDoc());
+    mBindingParent = do_QueryInterface(aContent->GetBindingParent());
+  } else {
+    mDocument = aContent->GetOwnerDoc();
+  }
+}
+
+const nsDependentSubstring
+IDRefsIterator::NextID()
+{
+  for (; mCurrIdx < mIDs.Length(); mCurrIdx++) {
+    if (!NS_IsAsciiWhitespace(mIDs[mCurrIdx]))
+      break;
+  }
+
+  if (mCurrIdx >= mIDs.Length())
+    return nsDependentSubstring();
+
+  nsAString::index_type idStartIdx = mCurrIdx;
+  while (++mCurrIdx < mIDs.Length()) {
+    if (NS_IsAsciiWhitespace(mIDs[mCurrIdx]))
+      break;
+  }
+
+  return Substring(mIDs, idStartIdx, mCurrIdx++ - idStartIdx);
+}
+
+nsIContent*
+IDRefsIterator::NextElem()
+{
+  while (true) {
+    const nsDependentSubstring id = NextID();
+    if (id.IsEmpty())
+      break;
+
+    if (mXBLDocument) {
+      // If content is anonymous subtree then use "anonid" attribute to get
+      // elements, otherwise search elements in DOM by ID attribute.
+
+      nsCOMPtr<nsIDOMElement> refElm;
+      mXBLDocument->GetAnonymousElementByAttribute(mBindingParent,
+                                                   NS_LITERAL_STRING("anonid"),
+                                                   id,
+                                                   getter_AddRefs(refElm));
+      nsCOMPtr<nsIContent> refContent = do_QueryInterface(refElm);
+      if (refContent)
+        return refContent;
+
+    } else {
+      nsIContent* refContent = mDocument->GetElementById(id);
+      if (refContent)
+        return refContent;
+    }
+  }
+
+  return nsnull;
+}

accessible/src/base/nsCoreUtils.h

@@ -41,6 +41,7 @@
 
 #include "nsAccessibilityAtoms.h"
 
+#include "nsIDOMDocumentXBL.h"
 #include "nsIDOMNode.h"
 #include "nsIContent.h"
 #include "nsIBoxObject.h"
@@ -304,17 +305,6 @@ public:
   static void GetLanguageFor(nsIContent *aContent, nsIContent *aRootContent,
                              nsAString& aLanguage);
 
-  /**
-   * Return the array of elements the given node is referred to by its
-   * IDRefs attribute.
-   *
-   * @param aContent     [in] the given node
-   * @param aAttr        [in] IDRefs attribute on the given node
-   * @param aRefElements [out] result array of elements
-   */
-  static void GetElementsByIDRefsAttr(nsIContent *aContent, nsIAtom *aAttr,
-                                      nsIArray **aRefElements);
-
   /**
    * Return the array of elements having IDRefs that points to the given node.
    *
@@ -515,5 +505,34 @@ private:
   nsTArray<nsString> mNames;
 };
 
+/**
+ * Used to iterate through IDs or elements pointed by IDRefs attribute. Note,
+ * any method used to iterate through IDs or elements moves iterator to next
+ * position.
+ */
+class IDRefsIterator
+{
+public:
+  IDRefsIterator(nsIContent* aContent, nsIAtom* aIDRefsAttr);
+
+  /**
+   * Return next ID.
+   */
+  const nsDependentSubstring NextID();
+
+  /**
+   * Return next element.
+   */
+  nsIContent* NextElem();
+
+private:
+  nsString mIDs;
+  nsAString::index_type mCurrIdx;
+
+  nsIDocument* mDocument;
+  nsCOMPtr<nsIDOMDocumentXBL> mXBLDocument;
+  nsCOMPtr<nsIDOMElement> mBindingParent;
+};
+
 #endif
 

accessible/src/base/nsRelUtils.cpp

@@ -134,27 +134,16 @@ nsRelUtils::AddTargetFromIDRefsAttr(PRUint32 aRelationType,
                                     nsIAccessibleRelation **aRelation,
                                     nsIContent *aContent, nsIAtom *aAttr)
 {
-  nsCOMPtr<nsIArray> refElms;
-  nsCoreUtils::GetElementsByIDRefsAttr(aContent, aAttr, getter_AddRefs(refElms));
+  nsresult rv = NS_OK_NO_RELATION_TARGET;
 
-  if (!refElms)
-    return NS_OK_NO_RELATION_TARGET;
-
-  PRUint32 count = 0;
-  nsresult rv = refElms->GetLength(&count);
-  if (NS_FAILED(rv) || count == 0)
-    return NS_OK_NO_RELATION_TARGET;
-
-  nsCOMPtr<nsIContent> content;
-  for (PRUint32 idx = 0; idx < count; idx++) {
-    content = do_QueryElementAt(refElms, idx, &rv);
-    NS_ENSURE_SUCCESS(rv, rv);
-
-    rv = AddTargetFromContent(aRelationType, aRelation, content);
+  nsIContent* refElm = nsnull;
+  IDRefsIterator iter(aContent, aAttr);
+  while ((refElm = iter.NextElem())) {
+    rv = AddTargetFromContent(aRelationType, aRelation, refElm);
     NS_ENSURE_SUCCESS(rv, rv);
   }
 
-  return NS_OK;
+  return rv;
 }
 
 nsresult

accessible/src/base/nsTextEquivUtils.cpp

@@ -92,26 +92,14 @@ nsTextEquivUtils::GetTextEquivFromIDRefs(nsAccessible *aAccessible,
   if (!content)
     return NS_OK;
 
-  nsCOMPtr<nsIArray> refElms;
-  nsCoreUtils::GetElementsByIDRefsAttr(content, aIDRefsAttr,
-                                       getter_AddRefs(refElms));
-
-  if (!refElms)
-    return NS_OK;
-
-  PRUint32 count = 0;
-  nsresult rv = refElms->GetLength(&count);
-  NS_ENSURE_SUCCESS(rv, rv);
-
-  nsCOMPtr<nsIContent> refContent;
-  for (PRUint32 idx = 0; idx < count; idx++) {
-    refContent = do_QueryElementAt(refElms, idx, &rv);
-    NS_ENSURE_SUCCESS(rv, rv);
-
+  nsIContent* refContent = nsnull;
+  IDRefsIterator iter(content, aIDRefsAttr);
+  while ((refContent = iter.NextElem())) {
     if (!aTextEquiv.IsEmpty())
       aTextEquiv += ' ';
 
-    rv = AppendTextEquivFromContent(aAccessible, refContent, &aTextEquiv);
+    nsresult rv = AppendTextEquivFromContent(aAccessible, refContent,
+                                             &aTextEquiv);
     NS_ENSURE_SUCCESS(rv, rv);
   }
 

accessible/src/html/nsHTMLTableAccessible.cpp

@@ -308,34 +308,27 @@ nsHTMLTableCellAccessible::GetHeaderCells(PRInt32 aRowOrColumnHeaderCell,
                                           nsIArray **aHeaderCells)
 {
   // Get header cells from @header attribute.
-  nsCOMPtr<nsIArray> headerCellElms;
-  nsCoreUtils::GetElementsByIDRefsAttr(mContent, nsAccessibilityAtoms::headers,
-                                       getter_AddRefs(headerCellElms));
-
-  if (headerCellElms) {
+  IDRefsIterator iter(mContent, nsAccessibilityAtoms::headers);
+  nsIContent* headerCellElm = iter.NextElem();
+  if (headerCellElm) {
     nsresult rv = NS_OK;
     nsCOMPtr<nsIMutableArray> headerCells =
       do_CreateInstance(NS_ARRAY_CONTRACTID, &rv);
     NS_ENSURE_SUCCESS(rv, rv);
 
-    PRUint32 count = 0;
-    rv = headerCellElms->GetLength(&count);
-    if (NS_SUCCEEDED(rv) && count > 0) {
-      nsCOMPtr<nsIContent> headerCellContent;
-      for (PRUint32 idx = 0; idx < count; idx++) {
-        headerCellContent = do_QueryElementAt(headerCellElms, idx, &rv);
-        nsAccessible *headerCell =
-          GetAccService()->GetAccessibleInWeakShell(headerCellContent, mWeakShell);
+    do {
+      nsAccessible* headerCell =
+        GetAccService()->GetAccessibleInWeakShell(headerCellElm, mWeakShell);
 
-        if (headerCell &&
-            (aRowOrColumnHeaderCell == nsAccUtils::eRowHeaderCells &&
-             headerCell->Role() == nsIAccessibleRole::ROLE_ROWHEADER ||
-             aRowOrColumnHeaderCell == nsAccUtils::eColumnHeaderCells &&
-             headerCell->Role() == nsIAccessibleRole::ROLE_COLUMNHEADER))
-          headerCells->AppendElement(static_cast<nsIAccessible*>(headerCell),
-                                     PR_FALSE);
+      if (headerCell &&
+          (aRowOrColumnHeaderCell == nsAccUtils::eRowHeaderCells &&
+              headerCell->Role() == nsIAccessibleRole::ROLE_ROWHEADER ||
+              aRowOrColumnHeaderCell == nsAccUtils::eColumnHeaderCells &&
+              headerCell->Role() == nsIAccessibleRole::ROLE_COLUMNHEADER)) {
+        headerCells->AppendElement(static_cast<nsIAccessible*>(headerCell),
+                                   PR_FALSE);
       }
-    }
+    } while ((headerCellElm = iter.NextElem()));
 
     NS_ADDREF(*aHeaderCells = headerCells);
     return NS_OK;