The Tor Browser: dom/promise/Promise.h@6474c204b198

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

     1 /* -*- Mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; tab-width: 40 -*- */

     2 /* vim: set ts=2 et sw=2 tw=80: */

     3 /* This Source Code Form is subject to the terms of the Mozilla Public

     4  * License, v. 2.0. If a copy of the MPL was not distributed with this file,

     5  * You can obtain one at http://mozilla.org/MPL/2.0/. */

     7 #ifndef mozilla_dom_Promise_h

     8 #define mozilla_dom_Promise_h

    10 #include "mozilla/Attributes.h"

    11 #include "mozilla/ErrorResult.h"

    12 #include "mozilla/TypeTraits.h"

    13 #include "mozilla/dom/BindingDeclarations.h"

    14 #include "nsCycleCollectionParticipant.h"

    15 #include "mozilla/dom/PromiseBinding.h"

    16 #include "mozilla/dom/ToJSValue.h"

    17 #include "nsWrapperCache.h"

    18 #include "nsAutoPtr.h"

    19 #include "js/TypeDecls.h"

    21 #include "mozilla/dom/workers/bindings/WorkerFeature.h"

    23 class nsIGlobalObject;

    25 namespace mozilla {

    26 namespace dom {

    28 class AnyCallback;

    29 class PromiseCallback;

    30 class PromiseInit;

    31 class PromiseNativeHandler;

    33 class Promise;

    34 class PromiseReportRejectFeature : public workers::WorkerFeature

    35 {

    36   // The Promise that owns this feature.

    37   Promise* mPromise;

    39 public:

    40   PromiseReportRejectFeature(Promise* aPromise)

    41     : mPromise(aPromise)

    42   {

    43     MOZ_ASSERT(mPromise);

    44   }

    46   virtual bool

    47   Notify(JSContext* aCx, workers::Status aStatus) MOZ_OVERRIDE;

    48 };

    50 class Promise MOZ_FINAL : public nsISupports,

    51                           public nsWrapperCache

    52 {

    53   friend class NativePromiseCallback;

    54   friend class PromiseResolverMixin;

    55   friend class PromiseResolverTask;

    56   friend class PromiseTask;

    57   friend class PromiseReportRejectFeature;

    58   friend class RejectPromiseCallback;

    59   friend class ResolvePromiseCallback;

    60   friend class WorkerPromiseResolverTask;

    61   friend class WorkerPromiseTask;

    62   friend class WrapperPromiseCallback;

    64   ~Promise();

    66 public:

    67   NS_DECL_CYCLE_COLLECTING_ISUPPORTS

    68   NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS(Promise)

    70   Promise(nsIGlobalObject* aGlobal);

    72   typedef void (Promise::*MaybeFunc)(JSContext* aCx,

    73                                      JS::Handle<JS::Value> aValue);

    75   void MaybeResolve(JSContext* aCx,

    76                     JS::Handle<JS::Value> aValue);

    77   void MaybeReject(JSContext* aCx,

    78                    JS::Handle<JS::Value> aValue);

    80   // Helpers for using Promise from C++.

    81   // Most DOM objects are handled already.  To add a new type T, add a

    82   // ToJSValue overload in ToJSValue.h.

    83   // aArg is a const reference so we can pass rvalues like integer constants

    84   template <typename T>

    85   void MaybeResolve(const T& aArg) {

    86     MaybeSomething(aArg, &Promise::MaybeResolve);

    87   }

    89   // aArg is a const reference so we can pass rvalues like NS_ERROR_*

    90   template <typename T>

    91   void MaybeReject(const T& aArg) {

    92     MaybeSomething(aArg, &Promise::MaybeReject);

    93   }

    95   // WebIDL

    97   nsIGlobalObject* GetParentObject() const

    98   {

    99     return mGlobal;

   100   }

   102   virtual JSObject*

   103   WrapObject(JSContext* aCx) MOZ_OVERRIDE;

   105   static already_AddRefed<Promise>

   106   Constructor(const GlobalObject& aGlobal, PromiseInit& aInit,

   107               ErrorResult& aRv);

   109   static already_AddRefed<Promise>

   110   Resolve(const GlobalObject& aGlobal, JSContext* aCx,

   111           JS::Handle<JS::Value> aValue, ErrorResult& aRv);

   113   static already_AddRefed<Promise>

   114   Resolve(nsIGlobalObject* aGlobal, JSContext* aCx,

   115           JS::Handle<JS::Value> aValue, ErrorResult& aRv);

   117   static already_AddRefed<Promise>

   118   Reject(const GlobalObject& aGlobal, JSContext* aCx,

   119          JS::Handle<JS::Value> aValue, ErrorResult& aRv);

   121   static already_AddRefed<Promise>

   122   Reject(nsIGlobalObject* aGlobal, JSContext* aCx,

   123          JS::Handle<JS::Value> aValue, ErrorResult& aRv);

   125   already_AddRefed<Promise>

   126   Then(JSContext* aCx, AnyCallback* aResolveCallback,

   127        AnyCallback* aRejectCallback);

   129   already_AddRefed<Promise>

   130   Catch(JSContext* aCx, AnyCallback* aRejectCallback);

   132   static already_AddRefed<Promise>

   133   All(const GlobalObject& aGlobal, JSContext* aCx,

   134       const Sequence<JS::Value>& aIterable, ErrorResult& aRv);

   136   static already_AddRefed<Promise>

   137   Race(const GlobalObject& aGlobal, JSContext* aCx,

   138        const Sequence<JS::Value>& aIterable, ErrorResult& aRv);

   140   void AppendNativeHandler(PromiseNativeHandler* aRunnable);

   142 private:

   143   enum PromiseState {

   144     Pending,

   145     Resolved,

   146     Rejected

   147   };

   149   enum PromiseTaskSync {

   150     SyncTask,

   151     AsyncTask

   152   };

   154   void SetState(PromiseState aState)

   155   {

   156     MOZ_ASSERT(mState == Pending);

   157     MOZ_ASSERT(aState != Pending);

   158     mState = aState;

   159   }

   161   void SetResult(JS::Handle<JS::Value> aValue)

   162   {

   163     mResult = aValue;

   164   }

   166   // This method processes promise's resolve/reject callbacks with promise's

   167   // result. It's executed when the resolver.resolve() or resolver.reject() is

   168   // called or when the promise already has a result and new callbacks are

   169   // appended by then(), catch() or done().

   170   void RunTask();

   172   void RunResolveTask(JS::Handle<JS::Value> aValue,

   173                       Promise::PromiseState aState,

   174                       PromiseTaskSync aAsynchronous);

   176   void AppendCallbacks(PromiseCallback* aResolveCallback,

   177                        PromiseCallback* aRejectCallback);

   179   // If we have been rejected and our mResult is a JS exception,

   180   // report it to the error console.

   181   // Use MaybeReportRejectedOnce() for actual calls.

   182   void MaybeReportRejected();

   184   void MaybeReportRejectedOnce() {

   185     MaybeReportRejected();

   186     RemoveFeature();

   187     mResult = JS::UndefinedValue();

   188   }

   190   void MaybeResolveInternal(JSContext* aCx,

   191                             JS::Handle<JS::Value> aValue,

   192                             PromiseTaskSync aSync = AsyncTask);

   193   void MaybeRejectInternal(JSContext* aCx,

   194                            JS::Handle<JS::Value> aValue,

   195                            PromiseTaskSync aSync = AsyncTask);

   197   void ResolveInternal(JSContext* aCx,

   198                        JS::Handle<JS::Value> aValue,

   199                        PromiseTaskSync aSync = AsyncTask);

   201   void RejectInternal(JSContext* aCx,

   202                       JS::Handle<JS::Value> aValue,

   203                       PromiseTaskSync aSync = AsyncTask);

   205   // Helper methods for using Promises from C++

   206   JSObject* GetOrCreateWrapper(JSContext* aCx);

   208   template <typename T>

   209   void MaybeSomething(T& aArgument, MaybeFunc aFunc) {

   210     ThreadsafeAutoJSContext cx;

   212     JSObject* wrapper = GetOrCreateWrapper(cx);

   213     if (!wrapper) {

   214       HandleException(cx);

   215       return;

   216     }

   218     JSAutoCompartment ac(cx, wrapper);

   219     JS::Rooted<JS::Value> val(cx);

   220     if (!ToJSValue(cx, aArgument, &val)) {

   221       HandleException(cx);

   222       return;

   223     }

   225     (this->*aFunc)(cx, val);

   226   }

   228   // Static methods for the PromiseInit functions.

   229   static bool

   230   JSCallback(JSContext *aCx, unsigned aArgc, JS::Value *aVp);

   232   static bool

   233   ThenableResolverCommon(JSContext* aCx, uint32_t /* PromiseCallback::Task */ aTask,

   234                          unsigned aArgc, JS::Value* aVp);

   235   static bool

   236   JSCallbackThenableResolver(JSContext *aCx, unsigned aArgc, JS::Value *aVp);

   237   static bool

   238   JSCallbackThenableRejecter(JSContext *aCx, unsigned aArgc, JS::Value *aVp);

   240   static JSObject*

   241   CreateFunction(JSContext* aCx, JSObject* aParent, Promise* aPromise,

   242                 int32_t aTask);

   244   static JSObject*

   245   CreateThenableFunction(JSContext* aCx, Promise* aPromise, uint32_t aTask);

   247   void HandleException(JSContext* aCx);

   249   void RemoveFeature();

   251   nsRefPtr<nsIGlobalObject> mGlobal;

   253   nsTArray<nsRefPtr<PromiseCallback> > mResolveCallbacks;

   254   nsTArray<nsRefPtr<PromiseCallback> > mRejectCallbacks;

   256   JS::Heap<JS::Value> mResult;

   257   PromiseState mState;

   258   bool mTaskPending;

   259   bool mHadRejectCallback;

   261   bool mResolvePending;

   263   // If a rejected promise on a worker has no reject callbacks attached, it

   264   // needs to know when the worker is shutting down, to report the error on the

   265   // console before the worker's context is deleted. This feature is used for

   266   // that purpose.

   267   nsAutoPtr<PromiseReportRejectFeature> mFeature;

   268 };

   270 } // namespace dom

   271 } // namespace mozilla

   273 #endif // mozilla_dom_Promise_h

The Tor Browser / file revision

dom/promise/Promise.h@6474c204b198

dom/promise/Promise.h