Bug 1392970 - Part 1: Make CustomElementDefinition ref-counted and put it in CustomElementData.

Tag UXP Issue #1344

7 files changed, 141 insertions, 50 deletions

diff --git a/dom/base/CustomElementRegistry.cpp b/dom/base/CustomElementRegistry.cpp
index 27e92a56a..b752fdda7 100644
--- a/dom/base/CustomElementRegistry.cpp
+++ b/dom/base/CustomElementRegistry.cpp
@@ -160,46 +160,15 @@ private:
 NS_IMPL_CYCLE_COLLECTION_CLASS(CustomElementRegistry)
 
 NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(CustomElementRegistry)
-  tmp->mCustomDefinitions.Clear();
   tmp->mConstructors.clear();
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mCustomDefinitions)
   NS_IMPL_CYCLE_COLLECTION_UNLINK(mWhenDefinedPromiseMap)
   NS_IMPL_CYCLE_COLLECTION_UNLINK(mWindow)
   NS_IMPL_CYCLE_COLLECTION_UNLINK_PRESERVED_WRAPPER
 NS_IMPL_CYCLE_COLLECTION_UNLINK_END
 
 NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(CustomElementRegistry)
-  for (auto iter = tmp->mCustomDefinitions.Iter(); !iter.Done(); iter.Next()) {
-    auto& callbacks = iter.UserData()->mCallbacks;
-
-    if (callbacks->mAttributeChangedCallback.WasPassed()) {
-      NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(cb,
-        "mCustomDefinitions->mCallbacks->mAttributeChangedCallback");
-      cb.NoteXPCOMChild(callbacks->mAttributeChangedCallback.Value());
-    }
-
-    if (callbacks->mCreatedCallback.WasPassed()) {
-      NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(cb,
-        "mCustomDefinitions->mCallbacks->mCreatedCallback");
-      cb.NoteXPCOMChild(callbacks->mCreatedCallback.Value());
-    }
-
-    if (callbacks->mAttachedCallback.WasPassed()) {
-      NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(cb,
-        "mCustomDefinitions->mCallbacks->mAttachedCallback");
-      cb.NoteXPCOMChild(callbacks->mAttachedCallback.Value());
-    }
-
-    if (callbacks->mDetachedCallback.WasPassed()) {
-      NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(cb,
-        "mCustomDefinitions->mCallbacks->mDetachedCallback");
-      cb.NoteXPCOMChild(callbacks->mDetachedCallback.Value());
-    }
-
-    NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(cb,
-      "mCustomDefinitions->mConstructor");
-    cb.NoteXPCOMChild(iter.UserData()->mConstructor);
-  }
-
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mCustomDefinitions)
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mWhenDefinedPromiseMap)
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mWindow)
 NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
@@ -256,7 +225,7 @@ CustomElementRegistry::LookupCustomElementDefinition(const nsAString& aLocalName
   nsCOMPtr<nsIAtom> localNameAtom = NS_Atomize(aLocalName);
   nsCOMPtr<nsIAtom> typeAtom = aIs ? NS_Atomize(*aIs) : localNameAtom;
 
-  CustomElementDefinition* data = mCustomDefinitions.Get(typeAtom);
+  CustomElementDefinition* data = mCustomDefinitions.GetWeak(typeAtom);
   if (data && data->mLocalName == localNameAtom) {
     return data;
   }
@@ -275,7 +244,7 @@ CustomElementRegistry::LookupCustomElementDefinition(JSContext* aCx,
     return nullptr;
   }
 
-  CustomElementDefinition* definition = mCustomDefinitions.Get(ptr->value());
+  CustomElementDefinition* definition = mCustomDefinitions.GetWeak(ptr->value());
   MOZ_ASSERT(definition, "Definition must be found in mCustomDefinitions");
 
   return definition;
@@ -294,7 +263,7 @@ CustomElementRegistry::RegisterUnresolvedElement(Element* aElement, nsIAtom* aTy
     typeName = info->NameAtom();
   }
 
-  if (mCustomDefinitions.Get(typeName)) {
+  if (mCustomDefinitions.GetWeak(typeName)) {
     return;
   }
 
@@ -368,7 +337,7 @@ CustomElementRegistry::CreateCustomElementCallback(
     nsCOMPtr<nsIAtom> typeAtom = elementData ?
       elementData->mType.get() : info->NameAtom();
 
-    definition = mCustomDefinitions.Get(typeAtom);
+    definition = mCustomDefinitions.GetWeak(typeAtom);
     if (!definition || definition->mLocalName != info->NameAtom()) {
       // Trying to enqueue a callback for an element that is not
       // a custom element. We are done, nothing to do.
@@ -447,7 +416,7 @@ CustomElementRegistry::EnqueueLifecycleCallback(nsIDocument::ElementCallbackType
     nsCOMPtr<nsIAtom> typeAtom = elementData ?
       elementData->mType.get() : info->NameAtom();
 
-    definition = mCustomDefinitions.Get(typeAtom);
+    definition = mCustomDefinitions.GetWeak(typeAtom);
     if (!definition || definition->mLocalName != info->NameAtom()) {
       return;
     }
@@ -482,7 +451,8 @@ void
 CustomElementRegistry::GetCustomPrototype(nsIAtom* aAtom,
                                           JS::MutableHandle<JSObject*> aPrototype)
 {
-  mozilla::dom::CustomElementDefinition* definition = mCustomDefinitions.Get(aAtom);
+  mozilla::dom::CustomElementDefinition* definition =
+    mCustomDefinitions.GetWeak(aAtom);
   if (definition) {
     aPrototype.set(definition->mPrototype);
   } else {
@@ -617,7 +587,7 @@ CustomElementRegistry::Define(const nsAString& aName,
    * 3. If this CustomElementRegistry contains an entry with name name, then
    *    throw a "NotSupportedError" DOMException and abort these steps.
    */
-  if (mCustomDefinitions.Get(nameAtom)) {
+  if (mCustomDefinitions.GetWeak(nameAtom)) {
     aRv.Throw(NS_ERROR_DOM_NOT_SUPPORTED_ERR);
     return;
   }
@@ -628,7 +598,7 @@ CustomElementRegistry::Define(const nsAString& aName,
    */
   const auto& ptr = mConstructors.lookup(constructorUnwrapped);
   if (ptr) {
-    MOZ_ASSERT(mCustomDefinitions.Get(ptr->value()),
+    MOZ_ASSERT(mCustomDefinitions.GetWeak(ptr->value()),
                "Definition must be found in mCustomDefinitions");
     aRv.Throw(NS_ERROR_DOM_NOT_SUPPORTED_ERR);
     return;
@@ -826,7 +796,7 @@ CustomElementRegistry::Define(const nsAString& aName,
     return;
   }
 
-  CustomElementDefinition* definition =
+  RefPtr<CustomElementDefinition> definition =
     new CustomElementDefinition(nameAtom,
                                 localNameAtom,
                                 &aFunctionConstructor,
@@ -835,7 +805,8 @@ CustomElementRegistry::Define(const nsAString& aName,
                                 callbacks,
                                 0 /* TODO dependent on HTML imports. Bug 877072 */);
 
-  mCustomDefinitions.Put(nameAtom, definition);
+  CustomElementDefinition* def = definition.get();
+  mCustomDefinitions.Put(nameAtom, definition.forget());
 
   MOZ_ASSERT(mCustomDefinitions.Count() == mConstructors.count(),
              "Number of entries should be the same");
@@ -843,7 +814,7 @@ CustomElementRegistry::Define(const nsAString& aName,
   /**
    * 13. 14. 15. Upgrade candidates
    */
-  UpgradeCandidates(nameAtom, definition, aRv);
+  UpgradeCandidates(nameAtom, def, aRv);
 
   /**
    * 16. If this CustomElementRegistry's when-defined promise map contains an
@@ -866,7 +837,7 @@ CustomElementRegistry::Get(JSContext* aCx, const nsAString& aName,
                            JS::MutableHandle<JS::Value> aRetVal)
 {
   nsCOMPtr<nsIAtom> nameAtom(NS_Atomize(aName));
-  CustomElementDefinition* data = mCustomDefinitions.Get(nameAtom);
+  CustomElementDefinition* data = mCustomDefinitions.GetWeak(nameAtom);
 
   if (!data) {
     aRetVal.setUndefined();
@@ -893,7 +864,7 @@ CustomElementRegistry::WhenDefined(const nsAString& aName, ErrorResult& aRv)
     return promise.forget();
   }
 
-  if (mCustomDefinitions.Get(nameAtom)) {
+  if (mCustomDefinitions.GetWeak(nameAtom)) {
     promise->MaybeResolve(JS::UndefinedHandleValue);
     return promise.forget();
   }
@@ -996,6 +967,9 @@ CustomElementRegistry::Upgrade(Element* aElement,
   // Step 8.
   data->mState = CustomElementData::State::eCustom;
 
+  // Step 9.
+  aElement->SetCustomElementDefinition(aDefinition);
+
   // This is for old spec.
   nsContentUtils::EnqueueLifecycleCallback(aElement->OwnerDoc(),
                                            nsIDocument::eCreated,
@@ -1148,6 +1122,49 @@ CustomElementReactionsStack::InvokeReactions(ElementQueue* aElementQueue,
 //-----------------------------------------------------
 // CustomElementDefinition
 
+NS_IMPL_CYCLE_COLLECTION_CLASS(CustomElementDefinition)
+
+NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(CustomElementDefinition)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mConstructor)
+  tmp->mPrototype = nullptr;
+  tmp->mCallbacks = nullptr;
+NS_IMPL_CYCLE_COLLECTION_UNLINK_END
+
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(CustomElementDefinition)
+  mozilla::dom::LifecycleCallbacks* callbacks = tmp->mCallbacks.get();
+
+  if (callbacks->mAttributeChangedCallback.WasPassed()) {
+    NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(cb,
+      "mCallbacks->mAttributeChangedCallback");
+    cb.NoteXPCOMChild(callbacks->mAttributeChangedCallback.Value());
+  }
+
+  if (callbacks->mCreatedCallback.WasPassed()) {
+    NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(cb, "mCallbacks->mCreatedCallback");
+    cb.NoteXPCOMChild(callbacks->mCreatedCallback.Value());
+  }
+
+  if (callbacks->mAttachedCallback.WasPassed()) {
+    NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(cb, "mCallbacks->mAttachedCallback");
+    cb.NoteXPCOMChild(callbacks->mAttachedCallback.Value());
+  }
+
+  if (callbacks->mDetachedCallback.WasPassed()) {
+    NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(cb, "mCallbacks->mDetachedCallback");
+    cb.NoteXPCOMChild(callbacks->mDetachedCallback.Value());
+  }
+
+  NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(cb, "mConstructor");
+  cb.NoteXPCOMChild(tmp->mConstructor);
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
+
+NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN(CustomElementDefinition)
+  NS_IMPL_CYCLE_COLLECTION_TRACE_JS_MEMBER_CALLBACK(mPrototype)
+NS_IMPL_CYCLE_COLLECTION_TRACE_END
+
+NS_IMPL_CYCLE_COLLECTION_ROOT_NATIVE(CustomElementDefinition, AddRef)
+NS_IMPL_CYCLE_COLLECTION_UNROOT_NATIVE(CustomElementDefinition, Release)
+
 CustomElementDefinition::CustomElementDefinition(nsIAtom* aType,
                                                  nsIAtom* aLocalName,
                                                  Function* aConstructor,
diff --git a/dom/base/CustomElementRegistry.h b/dom/base/CustomElementRegistry.h
index b731a1858..89e754365 100644
--- a/dom/base/CustomElementRegistry.h
+++ b/dom/base/CustomElementRegistry.h
@@ -13,7 +13,9 @@
 #include "mozilla/ErrorResult.h"
 #include "mozilla/dom/BindingDeclarations.h"
 #include "mozilla/dom/FunctionBinding.h"
+#include "mozilla/dom/WebComponentsBinding.h"
 #include "nsCycleCollectionParticipant.h"
+#include "nsGenericHTMLElement.h"
 #include "nsWrapperCache.h"
 
 class nsDocument;
@@ -23,7 +25,6 @@ namespace dom {
 
 struct CustomElementData;
 struct ElementDefinitionOptions;
-struct LifecycleCallbacks;
 class CallbackFunction;
 class CustomElementReaction;
 class Function;
@@ -115,6 +116,22 @@ struct CustomElementData
   // e.g., create an element, insert a node.
   AutoTArray<UniquePtr<CustomElementReaction>, 3> mReactionQueue;
 
+  RefPtr<CustomElementDefinition> mCustomElementDefinition;
+
+  void
+  SetCustomElementDefinition(CustomElementDefinition* aDefinition)
+  {
+    MOZ_ASSERT(!mCustomElementDefinition);
+
+    mCustomElementDefinition = aDefinition;
+  }
+
+  CustomElementDefinition*
+  GetCustomElementDefinition()
+  {
+    return mCustomElementDefinition;
+  }
+
 private:
   virtual ~CustomElementData() {}
 };
@@ -125,6 +142,9 @@ private:
 // https://html.spec.whatwg.org/multipage/scripting.html#custom-element-definition
 struct CustomElementDefinition
 {
+  NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_NATIVE_CLASS(CustomElementDefinition)
+  NS_INLINE_DECL_CYCLE_COLLECTING_NATIVE_REFCOUNTING(CustomElementDefinition)
+
   CustomElementDefinition(nsIAtom* aType,
                           nsIAtom* aLocalName,
                           Function* aConstructor,
@@ -170,6 +190,9 @@ struct CustomElementDefinition
 
     return mObservedAttributes.Contains(aName);
   }
+
+private:
+  ~CustomElementDefinition() {}
 };
 
 class CustomElementReaction
@@ -381,7 +404,7 @@ private:
                          CustomElementDefinition* aDefinition,
                          ErrorResult& aRv);
 
-  typedef nsClassHashtable<nsISupportsHashKey, CustomElementDefinition>
+  typedef nsRefPtrHashtable<nsISupportsHashKey, CustomElementDefinition>
     DefinitionMap;
   typedef nsClassHashtable<nsISupportsHashKey, nsTArray<nsWeakPtr>>
     CandidateMap;
diff --git a/dom/base/Element.cpp b/dom/base/Element.cpp
index 5719b423d..e90d44476 100644
--- a/dom/base/Element.cpp
+++ b/dom/base/Element.cpp
@@ -4065,3 +4065,23 @@ Element::SetCustomElementData(CustomElementData* aData)
   MOZ_ASSERT(!slots->mCustomElementData, "Custom element data may not be changed once set.");
   slots->mCustomElementData = aData;
 }
+
+CustomElementDefinition*
+Element::GetCustomElementDefinition() const
+{
+  CustomElementData* data = GetCustomElementData();
+  if (!data) {
+    return nullptr;
+  }
+
+  return data->GetCustomElementDefinition();
+}
+
+void
+Element::SetCustomElementDefinition(CustomElementDefinition* aDefinition)
+{
+  CustomElementData* data = GetCustomElementData();
+  MOZ_ASSERT(data);
+
+  data->SetCustomElementDefinition(aDefinition);
+}
diff --git a/dom/base/Element.h b/dom/base/Element.h
index e7218ee93..782004703 100644
--- a/dom/base/Element.h
+++ b/dom/base/Element.h
@@ -413,6 +413,22 @@ public:
    */
   void SetCustomElementData(CustomElementData* aData);
 
+  /**
+   * Gets the custom element definition used by web components custom element.
+   *
+   * @return The custom element definition or null if element is not a custom
+   *         element or custom element is not defined yet.
+   */
+  CustomElementDefinition* GetCustomElementDefinition() const;
+
+  /**
+   * Sets the custom element definition, called when custom element is created
+   * or upgraded.
+   *
+   * @param aDefinition The custom element definition.
+   */
+  void SetCustomElementDefinition(CustomElementDefinition* aDefinition);
+
 protected:
   /**
    * Method to get the _intrinsic_ content state of this element.  This is the
diff --git a/dom/base/FragmentOrElement.cpp b/dom/base/FragmentOrElement.cpp
index e341ae315..a851190ff 100644
--- a/dom/base/FragmentOrElement.cpp
+++ b/dom/base/FragmentOrElement.cpp
@@ -589,6 +589,13 @@ FragmentOrElement::nsDOMSlots::Traverse(nsCycleCollectionTraversalCallback &cb)
         mExtendedSlots->mCustomElementData->mReactionQueue[i]->Traverse(cb);
       }
     }
+
+    if (mExtendedSlots->mCustomElementData->mCustomElementDefinition) {
+      NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(cb,
+        "mExtendedSlots->mCustomElementData->mCustomElementDefinition");
+      cb.NoteNativeChild(mExtendedSlots->mCustomElementData->mCustomElementDefinition,
+        NS_CYCLE_COLLECTION_PARTICIPANT(CustomElementDefinition));
+    }
   }
 
   for (auto iter = mExtendedSlots->mRegisteredIntersectionObservers.Iter();
@@ -625,7 +632,12 @@ FragmentOrElement::nsDOMSlots::Unlink()
   mExtendedSlots->mContainingShadow = nullptr;
   MOZ_ASSERT(!(mExtendedSlots->mXBLBinding));
   mExtendedSlots->mXBLInsertionParent = nullptr;
-  mExtendedSlots->mCustomElementData = nullptr;
+  if (mExtendedSlots->mCustomElementData) {
+    if (mExtendedSlots->mCustomElementData->mCustomElementDefinition) {
+      mExtendedSlots->mCustomElementData->mCustomElementDefinition = nullptr;
+    }
+    mExtendedSlots->mCustomElementData = nullptr;
+  }
   mExtendedSlots->mRegisteredIntersectionObservers.Clear();
   nsCOMPtr<nsIFrameLoader> frameLoader =
     do_QueryInterface(mExtendedSlots->mFrameLoaderOrOpener);
diff --git a/dom/base/nsDocument.cpp b/dom/base/nsDocument.cpp
index 99f922c98..6c97750b9 100644
--- a/dom/base/nsDocument.cpp
+++ b/dom/base/nsDocument.cpp
@@ -5673,7 +5673,8 @@ nsDocument::CustomElementConstructor(JSContext* aCx, unsigned aArgc, JS::Value*
   }
 
   nsCOMPtr<nsIAtom> typeAtom(NS_Atomize(elemName));
-  CustomElementDefinition* definition = registry->mCustomDefinitions.Get(typeAtom);
+  CustomElementDefinition* definition =
+    registry->mCustomDefinitions.GetWeak(typeAtom);
   if (!definition) {
     return true;
   }
diff --git a/dom/bindings/BindingUtils.cpp b/dom/bindings/BindingUtils.cpp
index 3c31ec0e6..f76f14d95 100644
--- a/dom/bindings/BindingUtils.cpp
+++ b/dom/bindings/BindingUtils.cpp
@@ -3554,6 +3554,8 @@ CreateHTMLElement(const GlobalObject& aGlobal, const JS::CallArgs& aCallArgs,
     newElement->SetCustomElementData(
       new CustomElementData(definition->mType, CustomElementData::State::eCustom));
 
+    newElement->SetCustomElementDefinition(definition);
+
     return newElement.forget();
   }