Bug 288392, DOMSubtreeModified event, r=peterv, sr=jst

content/base/public/nsIDocument.h

@@ -90,11 +90,12 @@ template<class E> class nsCOMArray;
 class nsIDocumentObserver;
 class nsBindingManager;
 class nsIDOMNodeList;
+class mozAutoSubtreeModified;
 
 // IID for the nsIDocument interface
 #define NS_IDOCUMENT_IID      \
-{ 0x0b8acf09, 0x7877, 0x4928, \
- { 0x8b, 0xfb, 0x6d, 0x7c, 0x6d, 0x53, 0xff, 0x32 } }
+{ 0x1b8ed19c, 0xb87d, 0x4058, \
+  { 0x92, 0x2a, 0xff, 0xbc, 0x36, 0x29, 0x3b, 0xd7 } }
 
 // Flag for AddStyleSheet().
 #define NS_STYLESHEET_FROM_CATALOG                (1 << 0)
@@ -846,6 +847,11 @@ public:
    */
   virtual void FlushSkinBindings() = 0;
 
+  /**
+   * Returns PR_TRUE if one or more mutation events are being dispatched.
+   */
+  virtual PRBool MutationEventBeingDispatched() = 0;
+
 protected:
   ~nsIDocument()
   {
@@ -856,6 +862,15 @@ protected:
     // XXX Same thing applies to mBindingManager
   }
 
+  /**
+   * These methods should be called before and after dispatching
+   * a mutation event.
+   * To make this easy and painless, use the mozAutoSubtreeModified helper class.
+   */
+  virtual void WillDispatchMutationEvent(nsINode* aTarget) = 0;
+  virtual void MutationEventDispatched(nsINode* aTarget) = 0;
+  friend class mozAutoSubtreeModified;
+
   nsString mDocumentTitle;
   nsCOMPtr<nsIURI> mDocumentURI;
   nsCOMPtr<nsIURI> mDocumentBaseURI;
@@ -952,6 +967,48 @@ private:
   mozAutoDocUpdate MOZ_AUTO_DOC_UPDATE_PASTE(_autoDocUpdater_, __LINE__) \
   (doc,type,notify)
 
+/**
+ * mozAutoSubtreeModified batches DOM mutations so that a DOMSubtreeModified
+ * event is dispatched, if necessary, when the outermost mozAutoSubtreeModified
+ * object is deleted.
+ */
+class mozAutoSubtreeModified
+{
+public:
+  /**
+   * @param aSubTreeOwner The document in which a subtree will be modified.
+   * @param aTarget       The target of the possible DOMSubtreeModified event.
+   *                      Can be nsnull, in which case mozAutoSubtreeModified
+   *                      is just used to batch DOM mutations.
+   */
+  mozAutoSubtreeModified(nsIDocument* aSubtreeOwner, nsINode* aTarget)
+  {
+    UpdateTarget(aSubtreeOwner, aTarget);
+  }
+
+  ~mozAutoSubtreeModified()
+  {
+    UpdateTarget(nsnull, nsnull);
+  }
+
+  void UpdateTarget(nsIDocument* aSubtreeOwner, nsINode* aTarget)
+  {
+    if (mSubtreeOwner) {
+      mSubtreeOwner->MutationEventDispatched(mTarget);
+    }
+
+    mTarget = aTarget;
+    mSubtreeOwner = aSubtreeOwner;
+    if (mSubtreeOwner) {
+      mSubtreeOwner->WillDispatchMutationEvent(mTarget);
+    }
+  }
+
+private:
+  nsCOMPtr<nsINode>     mTarget;
+  nsCOMPtr<nsIDocument> mSubtreeOwner;
+};
+
 // XXX These belong somewhere else
 nsresult
 NS_NewHTMLDocument(nsIDocument** aInstancePtrResult);

content/base/src/nsContentUtils.cpp

@@ -2820,6 +2820,12 @@ nsContentUtils::HasMutationListeners(nsINode* aNode,
     return PR_FALSE;
   }
 
+  // To batch DOMSubtreeModified properly, all mutation events should be
+  // processed if one is being processed already.
+  if (doc->MutationEventBeingDispatched()) {
+    return PR_TRUE;
+  }
+
   // global object will be null for documents that don't have windows.
   nsCOMPtr<nsPIDOMWindow> window;
   window = do_QueryInterface(doc->GetScriptGlobalObject());

content/base/src/nsDocument.cpp

@@ -145,6 +145,7 @@ static NS_DEFINE_CID(kDOMEventGroupCID, NS_DOMEVENTGROUP_CID);
 #include "nsDateTimeFormatCID.h"
 #include "nsIDateTimeFormat.h"
 #include "nsEventDispatcher.h"
+#include "nsMutationEvent.h"
 #include "nsIDOMXPathEvaluator.h"
 #include "nsDOMCID.h"
 
@@ -5704,6 +5705,72 @@ nsDocument::OnPageHide(PRBool aPersisted)
   mVisible = PR_FALSE;
 }
 
+void
+nsDocument::WillDispatchMutationEvent(nsINode* aTarget)
+{
+  NS_ASSERTION(mSubtreeModifiedDepth != 0 ||
+               mSubtreeModifiedTargets.Count() == 0,
+               "mSubtreeModifiedTargets not cleared after dispatching?");
+  ++mSubtreeModifiedDepth;
+  if (aTarget) {
+    mSubtreeModifiedTargets.AppendObject(aTarget);
+  }
+}
+
+void
+nsDocument::MutationEventDispatched(nsINode* aTarget)
+{
+  --mSubtreeModifiedDepth;
+  if (mSubtreeModifiedDepth == 0) {
+    PRInt32 count = mSubtreeModifiedTargets.Count();
+    if (!count) {
+      return;
+    }
+
+    nsCOMPtr<nsPIDOMWindow> window;
+    window = do_QueryInterface(GetScriptGlobalObject());
+    if (window &&
+        !window->HasMutationListeners(NS_EVENT_BITS_MUTATION_SUBTREEMODIFIED)) {
+      mSubtreeModifiedTargets.Clear();
+      return;
+    }
+
+    nsCOMArray<nsINode> realTargets;
+    for (PRInt32 i = 0; i < count; ++i) {
+      nsINode* possibleTarget = mSubtreeModifiedTargets[i];
+      nsCOMPtr<nsIContent> content = do_QueryInterface(possibleTarget);
+      if (content && content->IsAnonymousForEvents()) {
+        if (realTargets.IndexOf(possibleTarget) == -1) {
+          realTargets.AppendObject(possibleTarget);
+        }
+        continue;
+      }
+
+      nsINode* commonAncestor = nsnull;
+      PRInt32 realTargetCount = realTargets.Count();
+      for (PRInt32 j = 0; j < realTargetCount; ++j) {
+        commonAncestor =
+          nsContentUtils::GetCommonAncestor(possibleTarget, realTargets[j]);
+        if (commonAncestor) {
+          realTargets.ReplaceObjectAt(commonAncestor, j);
+          break;
+        }
+      }
+      if (!commonAncestor) {
+        realTargets.AppendObject(possibleTarget);
+      }
+    }
+
+    mSubtreeModifiedTargets.Clear();
+
+    PRInt32 realTargetCount = realTargets.Count();
+    for (PRInt32 k = 0; k < realTargetCount; ++k) {
+      nsMutationEvent mutation(PR_TRUE, NS_MUTATION_SUBTREEMODIFIED);
+      nsEventDispatcher::Dispatch(realTargets[k], nsnull, &mutation);
+    }
+  }
+}
+
 static PRUint32 GetURIHash(nsIURI* aURI)
 {
   nsCAutoString str;

content/base/src/nsDocument.h

@@ -510,6 +510,13 @@ public:
   virtual void OnPageShow(PRBool aPersisted);
   virtual void OnPageHide(PRBool aPersisted);
   
+  virtual void WillDispatchMutationEvent(nsINode* aTarget);
+  virtual void MutationEventDispatched(nsINode* aTarget);
+  virtual PRBool MutationEventBeingDispatched()
+  {
+    return (mSubtreeModifiedDepth > 0);
+  }
+
   // nsINode
   virtual PRBool IsNodeOfType(PRUint32 aFlags) const;
   virtual nsIContent *GetChildAt(PRUint32 aIndex) const;
@@ -827,6 +834,9 @@ private:
   // Member to store out last-selected stylesheet set.
   nsString mLastStyleSheetSet;
 
+  nsCOMArray<nsINode> mSubtreeModifiedTargets;
+  PRUint32            mSubtreeModifiedDepth;
+
   // Our update nesting level
   PRUint32 mUpdateNestLevel;
 };

content/base/src/nsGenericDOMDataNode.cpp

@@ -470,6 +470,7 @@ nsGenericDOMDataNode::SetTextInternal(PRUint32 aOffset, PRUint32 aCount,
         mutation.mNewAttrValue = do_GetAtom(val);
       }
 
+      mozAutoSubtreeModified subtree(GetOwnerDoc(), this);
       nsEventDispatcher::Dispatch(this, nsnull, &mutation);
     }
 

content/base/src/nsGenericElement.cpp

@@ -346,6 +346,9 @@ nsNode3Tearoff::GetTextContent(nsAString &aTextContent)
 NS_IMETHODIMP
 nsNode3Tearoff::SetTextContent(const nsAString &aTextContent)
 {
+  // Batch possible DOMSubtreeModified events.
+  mozAutoSubtreeModified subtree(mContent->GetOwnerDoc(), nsnull);
+
   nsCOMPtr<nsIDOMNode> node(do_QueryInterface(mContent));
   NS_ASSERTION(node, "We have an nsIContent which doesn't support nsIDOMNode");
 
@@ -1667,6 +1670,9 @@ nsGenericElement::JoinTextNodes(nsIContent* aFirst,
 nsresult
 nsGenericElement::Normalize()
 {
+  // Batch possible DOMSubtreeModified events.
+  mozAutoSubtreeModified subtree(GetOwnerDoc(), nsnull);
+
   nsresult result = NS_OK;
   PRUint32 index, count = GetChildCount();
 
@@ -2343,6 +2349,7 @@ nsGenericElement::doInsertChildAt(nsIContent* aKid, PRUint32 aIndex,
           NS_EVENT_BITS_MUTATION_NODEINSERTED)) {
       nsMutationEvent mutation(PR_TRUE, NS_MUTATION_NODEINSERTED);
       mutation.mRelatedNode = do_QueryInterface(container);
+      mozAutoSubtreeModified subtree(container->GetOwnerDoc(), container);
       nsEventDispatcher::Dispatch(aKid, nsnull, &mutation);
     }
   }
@@ -2387,11 +2394,13 @@ nsGenericElement::doRemoveChildAt(PRUint32 aIndex, PRBool aNotify,
 
   nsMutationGuard guard;
 
+  mozAutoSubtreeModified subtree(nsnull, nsnull);
   if (aNotify &&
       nsContentUtils::HasMutationListeners(aKid,
         NS_EVENT_BITS_MUTATION_NODEREMOVED)) {
     nsMutationEvent mutation(PR_TRUE, NS_MUTATION_NODEREMOVED);
     mutation.mRelatedNode = do_QueryInterface(container);
+    subtree.UpdateTarget(container->GetOwnerDoc(), container);
     nsEventDispatcher::Dispatch(aKid, nsnull, &mutation);
   }
 
@@ -3326,6 +3335,7 @@ nsGenericElement::SetAttrAndNotify(PRInt32 aNamespaceID,
       mutation.mPrevAttrValue = do_GetAtom(aOldValue);
     }
     mutation.mAttrChange = modType;
+    mozAutoSubtreeModified subtree(GetOwnerDoc(), this);
     nsEventDispatcher::Dispatch(this, nsnull, &mutation);
   }
 
@@ -3553,6 +3563,7 @@ nsGenericElement::UnsetAttr(PRInt32 aNameSpaceID, nsIAtom* aName,
       mutation.mPrevAttrValue = do_GetAtom(value);
     mutation.mAttrChange = nsIDOMMutationEvent::REMOVAL;
 
+    mozAutoSubtreeModified subtree(GetOwnerDoc(), this);
     nsEventDispatcher::Dispatch(this, nsnull, &mutation);
   }
 

content/base/src/nsRange.cpp

@@ -1087,6 +1087,9 @@ nsresult nsRange::DeleteContents()
   if(IsDetached())
     return NS_ERROR_DOM_INVALID_STATE_ERR;
 
+  // Batch possible DOMSubtreeModified events.
+  mozAutoSubtreeModified subtree(mRoot ? mRoot->GetOwnerDoc(): nsnull, nsnull);
+
   // Save the range end points locally to avoid interference
   // of Range gravity during our edits!
 
@@ -1276,6 +1279,9 @@ nsresult nsRange::ExtractContents(nsIDOMDocumentFragment** aReturn)
   if(mIsDetached)
     return NS_ERROR_DOM_INVALID_STATE_ERR;
 
+  // Batch possible DOMSubtreeModified events.
+  mozAutoSubtreeModified subtree(mRoot ? mRoot->GetOwnerDoc(): nsnull, nsnull);
+
   // XXX_kin: The spec says that nodes that are completely in the
   // XXX_kin: range should be moved into the document fragment, not
   // XXX_kin: copied. This method will have to be rewritten using

content/events/public/nsIEventListenerManager.h

@@ -179,7 +179,8 @@ public:
    * Returns the mutation bits depending on which mutation listeners are
    * registered to this listener manager.
    * @note If a listener is an nsIDOMMutationListener, all possible mutation
-   *       event bits are returned.
+   *       event bits are returned. All bits are also returned if one of the
+   *       event listeners is registered to handle DOMSubtreeModified events.
    */
   virtual PRUint32 MutationListenerBits() = 0;
 };

content/events/src/nsEventListenerManager.cpp

@@ -527,7 +527,11 @@ nsEventListenerManager::AddEventListener(nsIDOMEventListener *aListener,
     if (window) {
       NS_ASSERTION(window->IsInnerWindow(),
                    "Setting mutation listener bits on outer window?");
-      window->SetMutationListeners(MutationBitForEventType(aType));
+      // If aType is NS_MUTATION_SUBTREEMODIFIED, we need to listen all
+      // mutations.
+      window->SetMutationListeners((aType == NS_MUTATION_SUBTREEMODIFIED) ?
+                                   kAllMutationBits :
+                                   MutationBitForEventType(aType));
     }
   }
 
@@ -1868,6 +1872,9 @@ nsEventListenerManager::MutationListenerBits()
       if (ls &&
           (ls->mEventType >= NS_MUTATION_START &&
            ls->mEventType <= NS_MUTATION_END)) {
+        if (ls->mEventType == NS_MUTATION_SUBTREEMODIFIED) {
+          return kAllMutationBits;
+        }
         bits |= MutationBitForEventType(ls->mEventType);
       }
     }

content/html/content/src/nsGenericHTMLElement.cpp

@@ -762,6 +762,9 @@ nsGenericHTMLElement::SetInnerHTML(const nsAString& aInnerHTML)
   // scriptloader before the last EndUpdate call.
   mozAutoDocUpdate updateBatch(GetCurrentDoc(), UPDATE_CONTENT_MODEL, PR_TRUE);
 
+  // Batch possible DOMSubtreeModified events.
+  mozAutoSubtreeModified subtree(GetOwnerDoc(), nsnull);
+
   // Remove childnodes
   nsContentUtils::SetNodeTextContent(this, EmptyString(), PR_FALSE);
 

content/xul/content/src/nsXULElement.cpp

@@ -1498,6 +1498,7 @@ nsXULElement::UnsetAttr(PRInt32 aNameSpaceID, nsIAtom* aName, PRBool aNotify)
           mutation.mPrevAttrValue = do_GetAtom(oldValue);
         mutation.mAttrChange = nsIDOMMutationEvent::REMOVAL;
 
+        mozAutoSubtreeModified subtree(GetOwnerDoc(), this);
         nsEventDispatcher::Dispatch(NS_STATIC_CAST(nsIContent*, this),
                                     nsnull, &mutation);
     }