gecko-dev/dom/base/CustomElementRegistry.h

540 строки
17 KiB
C++
Исходник Ответственный История

Этот файл содержит неоднозначные символы Юникода!

Этот файл содержит неоднозначные символы Юникода, которые могут быть перепутаны с другими в текущей локали. Если это намеренно, можете спокойно проигнорировать это предупреждение. Используйте кнопку Экранировать, чтобы подсветить эти символы.

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sw=2 sts=2 et cindent: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef mozilla_dom_CustomElementRegistry_h
#define mozilla_dom_CustomElementRegistry_h
#include "js/GCHashTable.h"
#include "js/TypeDecls.h"
#include "mozilla/Attributes.h"
#include "mozilla/ErrorResult.h"
#include "mozilla/dom/BindingDeclarations.h"
#include "mozilla/dom/Element.h"
#include "mozilla/dom/FunctionBinding.h"
#include "mozilla/dom/WebComponentsBinding.h"
#include "nsCycleCollectionParticipant.h"
#include "nsGenericHTMLElement.h"
#include "nsWrapperCache.h"
#include "nsContentUtils.h"
class nsDocument;
namespace mozilla {
namespace dom {
struct CustomElementData;
struct ElementDefinitionOptions;
class CallbackFunction;
class CustomElementReaction;
class Function;
class Promise;
struct LifecycleCallbackArgs
{
nsString name;
nsString oldValue;
nsString newValue;
nsString namespaceURI;
};
struct LifecycleAdoptedCallbackArgs
{
nsCOMPtr<nsIDocument> mOldDocument;
nsCOMPtr<nsIDocument> mNewDocument;
};
class CustomElementCallback
{
public:
CustomElementCallback(Element* aThisObject,
nsIDocument::ElementCallbackType aCallbackType,
CallbackFunction* aCallback,
CustomElementData* aOwnerData);
void Traverse(nsCycleCollectionTraversalCallback& aCb) const;
void Call();
void SetArgs(LifecycleCallbackArgs& aArgs)
{
MOZ_ASSERT(mType == nsIDocument::eAttributeChanged,
"Arguments are only used by attribute changed callback.");
mArgs = aArgs;
}
void SetAdoptedCallbackArgs(LifecycleAdoptedCallbackArgs& aAdoptedCallbackArgs)
{
MOZ_ASSERT(mType == nsIDocument::eAdopted,
"Arguments are only used by adopted callback.");
mAdoptedCallbackArgs = aAdoptedCallbackArgs;
}
private:
// The this value to use for invocation of the callback.
RefPtr<Element> mThisObject;
RefPtr<CallbackFunction> mCallback;
// The type of callback (eCreated, eAttached, etc.)
nsIDocument::ElementCallbackType mType;
// Arguments to be passed to the callback,
// used by the attribute changed callback.
LifecycleCallbackArgs mArgs;
LifecycleAdoptedCallbackArgs mAdoptedCallbackArgs;
// CustomElementData that contains this callback in the
// callback queue.
CustomElementData* mOwnerData;
};
class CustomElementConstructor final : public CallbackFunction
{
public:
explicit CustomElementConstructor(CallbackFunction* aOther)
: CallbackFunction(aOther)
{
MOZ_ASSERT(JS::IsConstructor(mCallback));
}
already_AddRefed<Element> Construct(const char* aExecutionReason, ErrorResult& aRv);
};
// Each custom element has an associated callback queue and an element is
// being created flag.
struct CustomElementData
{
NS_INLINE_DECL_REFCOUNTING(CustomElementData)
// https://dom.spec.whatwg.org/#concept-element-custom-element-state
// CustomElementData is only created on the element which is a custom element
// or an upgrade candidate, so the state of an element without
// CustomElementData is "uncustomized".
enum class State {
eUndefined,
eFailed,
eCustom
};
explicit CustomElementData(nsAtom* aType);
CustomElementData(nsAtom* aType, State aState);
// Custom element type, for <button is="x-button"> or <x-button>
// this would be x-button.
RefPtr<nsAtom> mType;
// Element is being created flag as described in the custom elements spec.
bool mElementIsBeingCreated;
// Flag to determine if the created callback has been invoked, thus it
// determines if other callbacks can be enqueued.
bool mCreatedCallbackInvoked;
// Custom element state as described in the custom element spec.
State mState;
// custom element reaction queue as described in the custom element spec.
// There is 1 reaction in reaction queue, when 1) it becomes disconnected,
// 2) its adopted into a new document, 3) its attributes are changed,
// appended, removed, or replaced.
// There are 3 reactions in reaction queue when doing upgrade operation,
// 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() {}
};
#define ALEADY_CONSTRUCTED_MARKER nullptr
// The required information for a custom element as defined in:
// 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(nsAtom* aType,
nsAtom* aLocalName,
Function* aConstructor,
nsTArray<RefPtr<nsAtom>>&& aObservedAttributes,
JSObject* aPrototype,
mozilla::dom::LifecycleCallbacks* aCallbacks,
uint32_t aDocOrder);
// The type (name) for this custom element.
RefPtr<nsAtom> mType;
// The localname to (e.g. <button is=type> -- this would be button).
RefPtr<nsAtom> mLocalName;
// The custom element constructor.
RefPtr<CustomElementConstructor> mConstructor;
// The list of attributes that this custom element observes.
nsTArray<RefPtr<nsAtom>> mObservedAttributes;
// The prototype to use for new custom elements of this type.
JS::Heap<JSObject *> mPrototype;
// The lifecycle callbacks to call for this custom element.
UniquePtr<mozilla::dom::LifecycleCallbacks> mCallbacks;
// A construction stack. Use nullptr to represent an "already constructed marker".
nsTArray<RefPtr<nsGenericHTMLElement>> mConstructionStack;
// The document custom element order.
uint32_t mDocOrder;
bool IsCustomBuiltIn()
{
return mType != mLocalName;
}
bool IsInObservedAttributeList(nsAtom* aName)
{
if (mObservedAttributes.IsEmpty()) {
return false;
}
return mObservedAttributes.Contains(aName);
}
private:
~CustomElementDefinition() {}
};
class CustomElementReaction
{
public:
explicit CustomElementReaction(CustomElementDefinition* aDefinition)
: mDefinition(aDefinition)
{
}
virtual ~CustomElementReaction() = default;
virtual void Invoke(Element* aElement, ErrorResult& aRv) = 0;
virtual void Traverse(nsCycleCollectionTraversalCallback& aCb) const
{
}
protected:
CustomElementDefinition* mDefinition;
};
class CustomElementUpgradeReaction final : public CustomElementReaction
{
public:
explicit CustomElementUpgradeReaction(CustomElementDefinition* aDefinition)
: CustomElementReaction(aDefinition)
{
}
private:
virtual void Invoke(Element* aElement, ErrorResult& aRv) override;
};
class CustomElementCallbackReaction final : public CustomElementReaction
{
public:
CustomElementCallbackReaction(CustomElementDefinition* aDefinition,
UniquePtr<CustomElementCallback> aCustomElementCallback)
: CustomElementReaction(aDefinition)
, mCustomElementCallback(Move(aCustomElementCallback))
{
}
virtual void Traverse(nsCycleCollectionTraversalCallback& aCb) const override
{
mCustomElementCallback->Traverse(aCb);
}
private:
virtual void Invoke(Element* aElement, ErrorResult& aRv) override;
UniquePtr<CustomElementCallback> mCustomElementCallback;
};
// https://html.spec.whatwg.org/multipage/scripting.html#custom-element-reactions-stack
class CustomElementReactionsStack
{
public:
NS_INLINE_DECL_REFCOUNTING(CustomElementReactionsStack)
CustomElementReactionsStack()
: mIsBackupQueueProcessing(false)
{
}
// Hold a strong reference of Element so that it does not get cycle collected
// before the reactions in its reaction queue are invoked.
// The element reaction queues are stored in CustomElementData.
// We need to lookup ElementReactionQueueMap again to get relevant reaction queue.
// The choice of 1 for the auto size here is based on gut feeling.
typedef AutoTArray<RefPtr<Element>, 1> ElementQueue;
/**
* Enqueue a custom element upgrade reaction
* https://html.spec.whatwg.org/multipage/scripting.html#enqueue-a-custom-element-upgrade-reaction
*/
void EnqueueUpgradeReaction(Element* aElement,
CustomElementDefinition* aDefinition);
/**
* Enqueue a custom element callback reaction
* https://html.spec.whatwg.org/multipage/scripting.html#enqueue-a-custom-element-callback-reaction
*/
void EnqueueCallbackReaction(Element* aElement,
CustomElementDefinition* aDefinition,
UniquePtr<CustomElementCallback> aCustomElementCallback);
// [CEReactions] Before executing the algorithm's steps
// Push a new element queue onto the custom element reactions stack.
void CreateAndPushElementQueue();
// [CEReactions] After executing the algorithm's steps
// Pop the element queue from the custom element reactions stack,
// and invoke custom element reactions in that queue.
void PopAndInvokeElementQueue();
private:
~CustomElementReactionsStack() {};
// The choice of 8 for the auto size here is based on gut feeling.
AutoTArray<UniquePtr<ElementQueue>, 8> mReactionsStack;
ElementQueue mBackupQueue;
// https://html.spec.whatwg.org/#enqueue-an-element-on-the-appropriate-element-queue
bool mIsBackupQueueProcessing;
void InvokeBackupQueue();
/**
* Invoke custom element reactions
* https://html.spec.whatwg.org/multipage/scripting.html#invoke-custom-element-reactions
*/
void InvokeReactions(ElementQueue* aElementQueue, nsIGlobalObject* aGlobal);
void Enqueue(Element* aElement, CustomElementReaction* aReaction);
private:
class ProcessBackupQueueRunnable : public mozilla::Runnable {
public:
explicit ProcessBackupQueueRunnable(
CustomElementReactionsStack* aReactionStack)
: Runnable(
"dom::CustomElementReactionsStack::ProcessBackupQueueRunnable")
, mReactionStack(aReactionStack)
{
MOZ_ASSERT(!mReactionStack->mIsBackupQueueProcessing,
"mIsBackupQueueProcessing should be initially false");
mReactionStack->mIsBackupQueueProcessing = true;
}
NS_IMETHOD Run() override
{
mReactionStack->InvokeBackupQueue();
mReactionStack->mIsBackupQueueProcessing = false;
return NS_OK;
}
private:
RefPtr<CustomElementReactionsStack> mReactionStack;
};
};
class CustomElementRegistry final : public nsISupports,
public nsWrapperCache
{
// Allow nsDocument to access mCustomDefinitions and mCandidatesMap.
friend class ::nsDocument;
public:
NS_DECL_CYCLE_COLLECTING_ISUPPORTS
NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS(CustomElementRegistry)
public:
static bool IsCustomElementEnabled(JSContext* aCx = nullptr,
JSObject* aObject = nullptr)
{
return nsContentUtils::IsCustomElementsEnabled() ||
nsContentUtils::IsWebComponentsEnabled();
}
explicit CustomElementRegistry(nsPIDOMWindowInner* aWindow);
/**
* Looking up a custom element definition.
* https://html.spec.whatwg.org/#look-up-a-custom-element-definition
*/
CustomElementDefinition* LookupCustomElementDefinition(
const nsAString& aLocalName, const nsAString* aIs = nullptr) const;
CustomElementDefinition* LookupCustomElementDefinition(
JSContext* aCx, JSObject *aConstructor) const;
/**
* Enqueue created callback or register upgrade candidate for
* newly created custom elements, possibly extending an existing type.
* ex. <x-button>, <button is="x-button> (type extension)
*/
void SetupCustomElement(Element* aElement, const nsAString* aTypeExtension);
static void EnqueueLifecycleCallback(nsIDocument::ElementCallbackType aType,
Element* aCustomElement,
LifecycleCallbackArgs* aArgs,
LifecycleAdoptedCallbackArgs* aAdoptedCallbackArgs,
CustomElementDefinition* aDefinition);
void GetCustomPrototype(nsAtom* aAtom,
JS::MutableHandle<JSObject*> aPrototype);
void SyncInvokeReactions(nsIDocument::ElementCallbackType aType,
Element* aCustomElement,
CustomElementDefinition* aDefinition);
/**
* Upgrade an element.
* https://html.spec.whatwg.org/multipage/scripting.html#upgrades
*/
static void Upgrade(Element* aElement, CustomElementDefinition* aDefinition, ErrorResult& aRv);
private:
~CustomElementRegistry();
static UniquePtr<CustomElementCallback> CreateCustomElementCallback(
nsIDocument::ElementCallbackType aType, Element* aCustomElement,
LifecycleCallbackArgs* aArgs,
LifecycleAdoptedCallbackArgs* aAdoptedCallbackArgs,
CustomElementDefinition* aDefinition);
/**
* Registers an unresolved custom element that is a candidate for
* upgrade when the definition is registered via registerElement.
* |aTypeName| is the name of the custom element type, if it is not
* provided, then element name is used. |aTypeName| should be provided
* when registering a custom element that extends an existing
* element. e.g. <button is="x-button">.
*/
void RegisterUnresolvedElement(Element* aElement,
nsAtom* aTypeName = nullptr);
void UpgradeCandidates(nsAtom* aKey,
CustomElementDefinition* aDefinition,
ErrorResult& aRv);
typedef nsRefPtrHashtable<nsRefPtrHashKey<nsAtom>, CustomElementDefinition>
DefinitionMap;
typedef nsClassHashtable<nsRefPtrHashKey<nsAtom>, nsTArray<nsWeakPtr>>
CandidateMap;
typedef JS::GCHashMap<JS::Heap<JSObject*>,
RefPtr<nsAtom>,
js::MovableCellHasher<JS::Heap<JSObject*>>,
js::SystemAllocPolicy> ConstructorMap;
// Hashtable for custom element definitions in web components.
// Custom prototypes are stored in the compartment where
// registerElement was called.
DefinitionMap mCustomDefinitions;
// Hashtable for looking up definitions by using constructor as key.
// Custom elements' name are stored here and we need to lookup
// mCustomDefinitions again to get definitions.
ConstructorMap mConstructors;
typedef nsRefPtrHashtable<nsRefPtrHashKey<nsAtom>, Promise>
WhenDefinedPromiseMap;
WhenDefinedPromiseMap mWhenDefinedPromiseMap;
// The "upgrade candidates map" from the web components spec. Maps from a
// namespace id and local name to a list of elements to upgrade if that
// element is registered as a custom element.
CandidateMap mCandidatesMap;
nsCOMPtr<nsPIDOMWindowInner> mWindow;
// It is used to prevent reentrant invocations of element definition.
bool mIsCustomDefinitionRunning;
private:
class MOZ_RAII AutoSetRunningFlag final {
public:
explicit AutoSetRunningFlag(CustomElementRegistry* aRegistry)
: mRegistry(aRegistry)
{
MOZ_ASSERT(!mRegistry->mIsCustomDefinitionRunning,
"IsCustomDefinitionRunning flag should be initially false");
mRegistry->mIsCustomDefinitionRunning = true;
}
~AutoSetRunningFlag() {
mRegistry->mIsCustomDefinitionRunning = false;
}
private:
CustomElementRegistry* mRegistry;
};
class SyncInvokeReactionRunnable : public mozilla::Runnable {
public:
SyncInvokeReactionRunnable(
UniquePtr<CustomElementReaction> aReaction, Element* aCustomElement)
: Runnable(
"dom::CustomElementRegistry::SyncInvokeReactionRunnable")
, mReaction(Move(aReaction))
, mCustomElement(aCustomElement)
{
}
NS_IMETHOD Run() override
{
// It'll never throw exceptions, because all the exceptions are handled
// by Lifecycle*Callback::Call function.
ErrorResult rv;
mReaction->Invoke(mCustomElement, rv);
return NS_OK;
}
private:
UniquePtr<CustomElementReaction> mReaction;
Element* mCustomElement;
};
public:
nsISupports* GetParentObject() const;
virtual JSObject* WrapObject(JSContext* aCx, JS::Handle<JSObject*> aGivenProto) override;
void Define(const nsAString& aName, Function& aFunctionConstructor,
const ElementDefinitionOptions& aOptions, ErrorResult& aRv);
void Get(JSContext* cx, const nsAString& name,
JS::MutableHandle<JS::Value> aRetVal);
already_AddRefed<Promise> WhenDefined(const nsAString& aName, ErrorResult& aRv);
};
class MOZ_RAII AutoCEReaction final {
public:
explicit AutoCEReaction(CustomElementReactionsStack* aReactionsStack)
: mReactionsStack(aReactionsStack) {
mReactionsStack->CreateAndPushElementQueue();
}
~AutoCEReaction() {
mReactionsStack->PopAndInvokeElementQueue();
}
private:
RefPtr<CustomElementReactionsStack> mReactionsStack;
};
} // namespace dom
} // namespace mozilla
#endif // mozilla_dom_CustomElementRegistry_h