diff options
Diffstat (limited to 'dom/promise/Promise.cpp')
| -rw-r--r-- | dom/promise/Promise.cpp | 2312 |
1 files changed, 1 insertions, 2311 deletions
diff --git a/dom/promise/Promise.cpp b/dom/promise/Promise.cpp index f636a91010..e5279345dc 100644 --- a/dom/promise/Promise.cpp +++ b/dom/promise/Promise.cpp @@ -30,7 +30,6 @@ #include "nsJSPrincipals.h" #include "nsJSUtils.h" #include "nsPIDOMWindow.h" -#include "PromiseCallback.h" #include "PromiseDebugging.h" #include "PromiseNativeHandler.h" #include "PromiseWorkerProxy.h" @@ -49,467 +48,45 @@ Atomic<uintptr_t> gIDGenerator(0); using namespace workers; -#ifndef SPIDERMONKEY_PROMISE -// This class processes the promise's callbacks with promise's result. -class PromiseReactionJob final : public Runnable -{ -public: - PromiseReactionJob(Promise* aPromise, - PromiseCallback* aCallback, - const JS::Value& aValue) - : mPromise(aPromise) - , mCallback(aCallback) - , mValue(CycleCollectedJSContext::Get()->Context(), aValue) - { - MOZ_ASSERT(aPromise); - MOZ_ASSERT(aCallback); - MOZ_COUNT_CTOR(PromiseReactionJob); - } - - virtual - ~PromiseReactionJob() - { - NS_ASSERT_OWNINGTHREAD(PromiseReactionJob); - MOZ_COUNT_DTOR(PromiseReactionJob); - } - -protected: - NS_IMETHOD - Run() override - { - NS_ASSERT_OWNINGTHREAD(PromiseReactionJob); - - MOZ_ASSERT(mPromise->GetWrapper()); // It was preserved! - - AutoJSAPI jsapi; - if (!jsapi.Init(mPromise->GetWrapper())) { - return NS_ERROR_FAILURE; - } - JSContext* cx = jsapi.cx(); - - JS::Rooted<JS::Value> value(cx, mValue); - if (!MaybeWrapValue(cx, &value)) { - NS_WARNING("Failed to wrap value into the right compartment."); - JS_ClearPendingException(cx); - return NS_OK; - } - - JS::Rooted<JSObject*> asyncStack(cx, mPromise->mAllocationStack); - - { - Maybe<JS::AutoSetAsyncStackForNewCalls> sas; - if (asyncStack) { - sas.emplace(cx, asyncStack, "Promise"); - } - mCallback->Call(cx, value); - } - - return NS_OK; - } - -private: - RefPtr<Promise> mPromise; - RefPtr<PromiseCallback> mCallback; - JS::PersistentRooted<JS::Value> mValue; - NS_DECL_OWNINGTHREAD; -}; - -/* - * Utilities for thenable callbacks. - * - * A thenable is a { then: function(resolve, reject) { } }. - * `then` is called with a resolve and reject callback pair. - * Since only one of these should be called at most once (first call wins), the - * two keep a reference to each other in SLOT_DATA. When either of them is - * called, the references are cleared. Further calls are ignored. - */ -namespace { -void -LinkThenableCallables(JSContext* aCx, JS::Handle<JSObject*> aResolveFunc, - JS::Handle<JSObject*> aRejectFunc) -{ - js::SetFunctionNativeReserved(aResolveFunc, Promise::SLOT_DATA, - JS::ObjectValue(*aRejectFunc)); - js::SetFunctionNativeReserved(aRejectFunc, Promise::SLOT_DATA, - JS::ObjectValue(*aResolveFunc)); -} - -/* - * Returns false if callback was already called before, otherwise breaks the - * links and returns true. - */ -bool -MarkAsCalledIfNotCalledBefore(JSContext* aCx, JS::Handle<JSObject*> aFunc) -{ - JS::Value otherFuncVal = - js::GetFunctionNativeReserved(aFunc, Promise::SLOT_DATA); - - if (!otherFuncVal.isObject()) { - return false; - } - - JSObject* otherFuncObj = &otherFuncVal.toObject(); - MOZ_ASSERT(js::GetFunctionNativeReserved(otherFuncObj, - Promise::SLOT_DATA).isObject()); - - // Break both references. - js::SetFunctionNativeReserved(aFunc, Promise::SLOT_DATA, - JS::UndefinedValue()); - js::SetFunctionNativeReserved(otherFuncObj, Promise::SLOT_DATA, - JS::UndefinedValue()); - - return true; -} - -Promise* -GetPromise(JSContext* aCx, JS::Handle<JSObject*> aFunc) -{ - JS::Value promiseVal = js::GetFunctionNativeReserved(aFunc, - Promise::SLOT_PROMISE); - - MOZ_ASSERT(promiseVal.isObject()); - - Promise* promise; - UNWRAP_OBJECT(Promise, &promiseVal.toObject(), promise); - return promise; -} -} // namespace - -// Runnable to resolve thenables. -// Equivalent to the specification's ResolvePromiseViaThenableTask. -class PromiseResolveThenableJob final : public Runnable -{ -public: - PromiseResolveThenableJob(Promise* aPromise, - JS::Handle<JSObject*> aThenable, - PromiseInit* aThen) - : mPromise(aPromise) - , mThenable(CycleCollectedJSContext::Get()->Context(), aThenable) - , mThen(aThen) - { - MOZ_ASSERT(aPromise); - MOZ_COUNT_CTOR(PromiseResolveThenableJob); - } - - virtual - ~PromiseResolveThenableJob() - { - NS_ASSERT_OWNINGTHREAD(PromiseResolveThenableJob); - MOZ_COUNT_DTOR(PromiseResolveThenableJob); - } - -protected: - NS_IMETHOD - Run() override - { - NS_ASSERT_OWNINGTHREAD(PromiseResolveThenableJob); - - MOZ_ASSERT(mPromise->GetWrapper()); // It was preserved! - - AutoJSAPI jsapi; - // If we ever change which compartment we're working in here, make sure to - // fix the fast-path for resolved-with-a-Promise in ResolveInternal. - if (!jsapi.Init(mPromise->GetWrapper())) { - return NS_ERROR_FAILURE; - } - JSContext* cx = jsapi.cx(); - - JS::Rooted<JSObject*> resolveFunc(cx, - mPromise->CreateThenableFunction(cx, mPromise, PromiseCallback::Resolve)); - - if (!resolveFunc) { - mPromise->HandleException(cx); - return NS_OK; - } - - JS::Rooted<JSObject*> rejectFunc(cx, - mPromise->CreateThenableFunction(cx, mPromise, PromiseCallback::Reject)); - if (!rejectFunc) { - mPromise->HandleException(cx); - return NS_OK; - } - - LinkThenableCallables(cx, resolveFunc, rejectFunc); - - ErrorResult rv; - - JS::Rooted<JSObject*> rootedThenable(cx, mThenable); - - mThen->Call(rootedThenable, resolveFunc, rejectFunc, rv, - "promise thenable", CallbackObject::eRethrowExceptions, - mPromise->Compartment()); - - rv.WouldReportJSException(); - if (rv.Failed()) { - JS::Rooted<JS::Value> exn(cx); - { // Scope for JSAutoCompartment - - // Convert the ErrorResult to a JS exception object that we can reject - // ourselves with. This will be exactly the exception that would get - // thrown from a binding method whose ErrorResult ended up with - // whatever is on "rv" right now. - JSAutoCompartment ac(cx, mPromise->GlobalJSObject()); - DebugOnly<bool> conversionResult = ToJSValue(cx, rv, &exn); - MOZ_ASSERT(conversionResult); - } - - bool couldMarkAsCalled = MarkAsCalledIfNotCalledBefore(cx, resolveFunc); - - // If we could mark as called, neither of the callbacks had been called - // when the exception was thrown. So we can reject the Promise. - if (couldMarkAsCalled) { - bool ok = JS_WrapValue(cx, &exn); - MOZ_ASSERT(ok); - if (!ok) { - NS_WARNING("Failed to wrap value into the right compartment."); - } - - mPromise->RejectInternal(cx, exn); - } - // At least one of resolveFunc or rejectFunc have been called, so ignore - // the exception. FIXME(nsm): This should be reported to the error - // console though, for debugging. - } - - return rv.StealNSResult(); - } - -private: - RefPtr<Promise> mPromise; - JS::PersistentRooted<JSObject*> mThenable; - RefPtr<PromiseInit> mThen; - NS_DECL_OWNINGTHREAD; -}; - -// A struct implementing -// <http://www.ecma-international.org/ecma-262/6.0/#sec-promisecapability-records>. -// While the spec holds on to these in some places, in practice those places -// don't actually need everything from this struct, so we explicitly grab -// members from it as needed in those situations. That allows us to make this a -// stack-only struct and keep the rooting simple. -// -// We also add an optimization for the (common) case when we discover that the -// Promise constructor we're supposed to use is in fact the canonical Promise -// constructor. In that case we will just set mNativePromise in our -// PromiseCapability and not set mPromise/mResolve/mReject; the correct -// callbacks will be the standard Promise ones, and we don't really want to -// synthesize JSFunctions for them in that situation. -struct MOZ_STACK_CLASS Promise::PromiseCapability -{ - explicit PromiseCapability(JSContext* aCx) - : mPromise(aCx) - , mResolve(aCx) - , mReject(aCx) - {} - - // Take an exception on aCx and try to convert it into a promise rejection. - // Note that this can result in a new exception being thrown on aCx, or an - // exception getting thrown on aRv. On entry to this method, aRv is assumed - // to not be a failure. This should only be called if NewPromiseCapability - // succeeded on this PromiseCapability. - void RejectWithException(JSContext* aCx, ErrorResult& aRv); - - // Return a JS::Value representing the promise. This should only be called if - // NewPromiseCapability succeeded on this PromiseCapability. It makes no - // guarantees about compartments (e.g. in the mNativePromise case it's in the - // compartment of the reflector, but in the mPromise case it might be in the - // compartment of some cross-compartment wrapper for a reflector). - JS::Value PromiseValue() const; - - // All the JS::Value fields of this struct are actually objects, but for our - // purposes it's simpler to store them as JS::Value. - - // [[Promise]]. - JS::Rooted<JSObject*> mPromise; - // [[Resolve]]. Value in the context compartment. - JS::Rooted<JS::Value> mResolve; - // [[Reject]]. Value in the context compartment. - JS::Rooted<JS::Value> mReject; - // If mNativePromise is non-null, we should use it, not mPromise. - RefPtr<Promise> mNativePromise; - -private: - // We don't want to allow creation of temporaries of this type, ever. - PromiseCapability(const PromiseCapability&) = delete; - PromiseCapability(PromiseCapability&&) = delete; -}; - -void -Promise::PromiseCapability::RejectWithException(JSContext* aCx, - ErrorResult& aRv) -{ - // This method basically implements - // http://www.ecma-international.org/ecma-262/6.0/#sec-ifabruptrejectpromise - // or at least the parts of it that happen if we have an abrupt completion. - - MOZ_ASSERT(!aRv.Failed()); - MOZ_ASSERT(mNativePromise || mPromise, - "NewPromiseCapability didn't succeed"); - - JS::Rooted<JS::Value> exn(aCx); - if (!JS_GetPendingException(aCx, &exn)) { - // This is an uncatchable exception, so can't be converted into a rejection. - // Just rethrow that on aRv. - aRv.ThrowUncatchableException(); - return; - } - - JS_ClearPendingException(aCx); - - // If we have a native promise, just reject it without trying to call out into - // JS. - if (mNativePromise) { - mNativePromise->MaybeRejectInternal(aCx, exn); - return; - } - - JS::Rooted<JS::Value> ignored(aCx); - if (!JS::Call(aCx, JS::UndefinedHandleValue, mReject, JS::HandleValueArray(exn), - &ignored)) { - aRv.NoteJSContextException(aCx); - } -} - -JS::Value -Promise::PromiseCapability::PromiseValue() const -{ - MOZ_ASSERT(mNativePromise || mPromise, - "NewPromiseCapability didn't succeed"); - - if (mNativePromise) { - return JS::ObjectValue(*mNativePromise->GetWrapper()); - } - - return JS::ObjectValue(*mPromise); -} - -#endif // SPIDERMONKEY_PROMISE - // Promise NS_IMPL_CYCLE_COLLECTION_CLASS(Promise) NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(Promise) -#ifndef SPIDERMONKEY_PROMISE -#if defined(DOM_PROMISE_DEPRECATED_REPORTING) - tmp->MaybeReportRejectedOnce(); -#else - tmp->mResult = JS::UndefinedValue(); -#endif // defined(DOM_PROMISE_DEPRECATED_REPORTING) -#endif // SPIDERMONKEY_PROMISE NS_IMPL_CYCLE_COLLECTION_UNLINK(mGlobal) -#ifndef SPIDERMONKEY_PROMISE - NS_IMPL_CYCLE_COLLECTION_UNLINK(mResolveCallbacks) - NS_IMPL_CYCLE_COLLECTION_UNLINK(mRejectCallbacks) - NS_IMPL_CYCLE_COLLECTION_UNLINK_PRESERVED_WRAPPER -#else // SPIDERMONKEY_PROMISE tmp->mPromiseObj = nullptr; -#endif // SPIDERMONKEY_PROMISE NS_IMPL_CYCLE_COLLECTION_UNLINK_END NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(Promise) NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mGlobal) -#ifndef SPIDERMONKEY_PROMISE - NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mResolveCallbacks) - NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mRejectCallbacks) -#endif // SPIDERMONKEY_PROMISE NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN(Promise) -#ifndef SPIDERMONKEY_PROMISE - NS_IMPL_CYCLE_COLLECTION_TRACE_JS_MEMBER_CALLBACK(mResult) - NS_IMPL_CYCLE_COLLECTION_TRACE_JS_MEMBER_CALLBACK(mAllocationStack) - NS_IMPL_CYCLE_COLLECTION_TRACE_JS_MEMBER_CALLBACK(mRejectionStack) - NS_IMPL_CYCLE_COLLECTION_TRACE_JS_MEMBER_CALLBACK(mFullfillmentStack) - NS_IMPL_CYCLE_COLLECTION_TRACE_PRESERVED_WRAPPER -#else // SPIDERMONKEY_PROMISE NS_IMPL_CYCLE_COLLECTION_TRACE_JS_MEMBER_CALLBACK(mPromiseObj); -#endif // SPIDERMONKEY_PROMISE NS_IMPL_CYCLE_COLLECTION_TRACE_END -#ifndef SPIDERMONKEY_PROMISE -NS_IMPL_CYCLE_COLLECTION_CAN_SKIP_BEGIN(Promise) - if (tmp->IsBlack()) { - tmp->mResult.exposeToActiveJS(); - tmp->mAllocationStack.exposeToActiveJS(); - tmp->mRejectionStack.exposeToActiveJS(); - tmp->mFullfillmentStack.exposeToActiveJS(); - return true; - } -NS_IMPL_CYCLE_COLLECTION_CAN_SKIP_END - -NS_IMPL_CYCLE_COLLECTION_CAN_SKIP_IN_CC_BEGIN(Promise) - return tmp->IsBlackAndDoesNotNeedTracing(tmp); -NS_IMPL_CYCLE_COLLECTION_CAN_SKIP_IN_CC_END - -NS_IMPL_CYCLE_COLLECTION_CAN_SKIP_THIS_BEGIN(Promise) - return tmp->IsBlack(); -NS_IMPL_CYCLE_COLLECTION_CAN_SKIP_THIS_END -#endif // SPIDERMONKEY_PROMISE - NS_IMPL_CYCLE_COLLECTING_ADDREF(Promise) NS_IMPL_CYCLE_COLLECTING_RELEASE(Promise) NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(Promise) -#ifndef SPIDERMONKEY_PROMISE - NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY -#endif // SPIDERMONKEY_PROMISE NS_INTERFACE_MAP_ENTRY(nsISupports) NS_INTERFACE_MAP_ENTRY(Promise) NS_INTERFACE_MAP_END Promise::Promise(nsIGlobalObject* aGlobal) : mGlobal(aGlobal) -#ifndef SPIDERMONKEY_PROMISE - , mResult(JS::UndefinedValue()) - , mAllocationStack(nullptr) - , mRejectionStack(nullptr) - , mFullfillmentStack(nullptr) - , mState(Pending) -#if defined(DOM_PROMISE_DEPRECATED_REPORTING) - , mHadRejectCallback(false) -#endif // defined(DOM_PROMISE_DEPRECATED_REPORTING) - , mTaskPending(false) - , mResolvePending(false) - , mIsLastInChain(true) - , mWasNotifiedAsUncaught(false) - , mID(0) -#else // SPIDERMONKEY_PROMISE , mPromiseObj(nullptr) -#endif // SPIDERMONKEY_PROMISE { MOZ_ASSERT(mGlobal); mozilla::HoldJSObjects(this); - -#ifndef SPIDERMONKEY_PROMISE - mCreationTimestamp = TimeStamp::Now(); -#endif // SPIDERMONKEY_PROMISE } Promise::~Promise() { -#ifndef SPIDERMONKEY_PROMISE -#if defined(DOM_PROMISE_DEPRECATED_REPORTING) - MaybeReportRejectedOnce(); -#endif // defined(DOM_PROMISE_DEPRECATED_REPORTING) -#endif // SPIDERMONKEY_PROMISE mozilla::DropJSObjects(this); } -#ifdef SPIDERMONKEY_PROMISE - -bool -Promise::WrapObject(JSContext* aCx, JS::Handle<JSObject*> aGivenProto, - JS::MutableHandle<JSObject*> aWrapper) -{ -#ifdef DEBUG - binding_detail::AssertReflectorHasGivenProto(aCx, mPromiseObj, aGivenProto); -#endif // DEBUG - aWrapper.set(mPromiseObj); - return true; -} - // static already_AddRefed<Promise> Promise::Create(nsIGlobalObject* aGlobal, ErrorResult& aRv) @@ -884,8 +461,7 @@ Promise::HandleException(JSContext* aCx) JS::Rooted<JS::Value> exn(aCx); if (JS_GetPendingException(aCx, &exn)) { JS_ClearPendingException(aCx); - // This is only called from MaybeSomething, so it's OK to MaybeReject here, - // unlike in the version that's used when !SPIDERMONKEY_PROMISE. + // This is only called from MaybeSomething, so it's OK to MaybeReject here. MaybeReject(aCx, exn); } } @@ -902,80 +478,6 @@ Promise::CreateFromExisting(nsIGlobalObject* aGlobal, return p.forget(); } -#else // SPIDERMONKEY_PROMISE - -JSObject* -Promise::WrapObject(JSContext* aCx, JS::Handle<JSObject*> aGivenProto) -{ - return PromiseBinding::Wrap(aCx, this, aGivenProto); -} - -already_AddRefed<Promise> -Promise::Create(nsIGlobalObject* aGlobal, ErrorResult& aRv, - JS::Handle<JSObject*> aDesiredProto) -{ - if (!aGlobal) { - aRv.Throw(NS_ERROR_UNEXPECTED); - return nullptr; - } - RefPtr<Promise> p = new Promise(aGlobal); - p->CreateWrapper(aDesiredProto, aRv); - if (aRv.Failed()) { - return nullptr; - } - return p.forget(); -} - -void -Promise::CreateWrapper(JS::Handle<JSObject*> aDesiredProto, ErrorResult& aRv) -{ - AutoJSAPI jsapi; - if (!jsapi.Init(mGlobal)) { - aRv.Throw(NS_ERROR_UNEXPECTED); - return; - } - JSContext* cx = jsapi.cx(); - - JS::Rooted<JS::Value> wrapper(cx); - if (!GetOrCreateDOMReflector(cx, this, &wrapper, aDesiredProto)) { - JS_ClearPendingException(cx); - aRv.Throw(NS_ERROR_OUT_OF_MEMORY); - return; - } - - dom::PreserveWrapper(this); - - // Now grab our allocation stack - if (!CaptureStack(cx, mAllocationStack)) { - JS_ClearPendingException(cx); - aRv.Throw(NS_ERROR_OUT_OF_MEMORY); - return; - } - - JS::RootedObject obj(cx, &wrapper.toObject()); - JS::dbg::onNewPromise(cx, obj); -} - -void -Promise::MaybeResolve(JSContext* aCx, - JS::Handle<JS::Value> aValue) -{ - NS_ASSERT_OWNINGTHREAD(Promise); - - MaybeResolveInternal(aCx, aValue); -} - -void -Promise::MaybeReject(JSContext* aCx, - JS::Handle<JS::Value> aValue) -{ - NS_ASSERT_OWNINGTHREAD(Promise); - - MaybeRejectInternal(aCx, aValue); -} - -#endif // SPIDERMONKEY_PROMISE - void Promise::MaybeResolveWithUndefined() { @@ -999,7 +501,6 @@ Promise::MaybeRejectWithUndefined() MaybeSomething(JS::UndefinedHandleValue, &Promise::MaybeReject); } -#ifdef SPIDERMONKEY_PROMISE void Promise::ReportRejectedPromise(JSContext* aCx, JS::HandleObject aPromise) { @@ -1026,7 +527,6 @@ Promise::ReportRejectedPromise(JSContext* aCx, JS::HandleObject aPromise) // Now post an event to do the real reporting async NS_DispatchToMainThread(new AsyncErrorReporter(xpcReport)); } -#endif // defined(SPIDERMONKEY_PROMISE) bool Promise::PerformMicroTaskCheckpoint() @@ -1132,1422 +632,6 @@ Promise::PerformWorkerDebuggerMicroTaskCheckpoint() } } -#ifndef SPIDERMONKEY_PROMISE - -/* static */ bool -Promise::JSCallback(JSContext* aCx, unsigned aArgc, JS::Value* aVp) -{ - JS::CallArgs args = CallArgsFromVp(aArgc, aVp); - - JS::Rooted<JS::Value> v(aCx, - js::GetFunctionNativeReserved(&args.callee(), - SLOT_PROMISE)); - MOZ_ASSERT(v.isObject()); - - Promise* promise; - if (NS_FAILED(UNWRAP_OBJECT(Promise, &v.toObject(), promise))) { - return Throw(aCx, NS_ERROR_UNEXPECTED); - } - - v = js::GetFunctionNativeReserved(&args.callee(), SLOT_DATA); - PromiseCallback::Task task = static_cast<PromiseCallback::Task>(v.toInt32()); - - if (task == PromiseCallback::Resolve) { - if (!promise->CaptureStack(aCx, promise->mFullfillmentStack)) { - return false; - } - promise->MaybeResolveInternal(aCx, args.get(0)); - } else { - promise->MaybeRejectInternal(aCx, args.get(0)); - if (!promise->CaptureStack(aCx, promise->mRejectionStack)) { - return false; - } - } - - args.rval().setUndefined(); - return true; -} - -/* - * Common bits of (JSCallbackThenableResolver/JSCallbackThenableRejecter). - * Resolves/rejects the Promise if it is ok to do so, based on whether either of - * the callbacks have been called before or not. - */ -/* static */ bool -Promise::ThenableResolverCommon(JSContext* aCx, uint32_t aTask, - unsigned aArgc, JS::Value* aVp) -{ - JS::CallArgs args = CallArgsFromVp(aArgc, aVp); - JS::Rooted<JSObject*> thisFunc(aCx, &args.callee()); - if (!MarkAsCalledIfNotCalledBefore(aCx, thisFunc)) { - // A function from this pair has been called before. - args.rval().setUndefined(); - return true; - } - - Promise* promise = GetPromise(aCx, thisFunc); - MOZ_ASSERT(promise); - - if (aTask == PromiseCallback::Resolve) { - promise->ResolveInternal(aCx, args.get(0)); - } else { - promise->RejectInternal(aCx, args.get(0)); - } - - args.rval().setUndefined(); - return true; -} - -/* static */ bool -Promise::JSCallbackThenableResolver(JSContext* aCx, - unsigned aArgc, JS::Value* aVp) -{ - return ThenableResolverCommon(aCx, PromiseCallback::Resolve, aArgc, aVp); -} - -/* static */ bool -Promise::JSCallbackThenableRejecter(JSContext* aCx, - unsigned aArgc, JS::Value* aVp) -{ - return ThenableResolverCommon(aCx, PromiseCallback::Reject, aArgc, aVp); -} - -/* static */ JSObject* -Promise::CreateFunction(JSContext* aCx, Promise* aPromise, int32_t aTask) -{ - // If this function ever changes, make sure to update - // WrapperPromiseCallback::GetDependentPromise. - JSFunction* func = js::NewFunctionWithReserved(aCx, JSCallback, - 1 /* nargs */, 0 /* flags */, - nullptr); - if (!func) { - return nullptr; - } - - JS::Rooted<JSObject*> obj(aCx, JS_GetFunctionObject(func)); - - JS::Rooted<JS::Value> promiseObj(aCx); - if (!dom::GetOrCreateDOMReflector(aCx, aPromise, &promiseObj)) { - return nullptr; - } - - JS::ExposeValueToActiveJS(promiseObj); - js::SetFunctionNativeReserved(obj, SLOT_PROMISE, promiseObj); - js::SetFunctionNativeReserved(obj, SLOT_DATA, JS::Int32Value(aTask)); - - return obj; -} - -/* static */ JSObject* -Promise::CreateThenableFunction(JSContext* aCx, Promise* aPromise, uint32_t aTask) -{ - JSNative whichFunc = - aTask == PromiseCallback::Resolve ? JSCallbackThenableResolver : - JSCallbackThenableRejecter ; - - JSFunction* func = js::NewFunctionWithReserved(aCx, whichFunc, - 1 /* nargs */, 0 /* flags */, - nullptr); - if (!func) { - return nullptr; - } - - JS::Rooted<JSObject*> obj(aCx, JS_GetFunctionObject(func)); - - JS::Rooted<JS::Value> promiseObj(aCx); - if (!dom::GetOrCreateDOMReflector(aCx, aPromise, &promiseObj)) { - return nullptr; - } - - JS::ExposeValueToActiveJS(promiseObj); - js::SetFunctionNativeReserved(obj, SLOT_PROMISE, promiseObj); - - return obj; -} - -/* static */ already_AddRefed<Promise> -Promise::Constructor(const GlobalObject& aGlobal, PromiseInit& aInit, - ErrorResult& aRv, JS::Handle<JSObject*> aDesiredProto) -{ - nsCOMPtr<nsIGlobalObject> global; - global = do_QueryInterface(aGlobal.GetAsSupports()); - if (!global) { - aRv.Throw(NS_ERROR_UNEXPECTED); - return nullptr; - } - - RefPtr<Promise> promise = Create(global, aRv, aDesiredProto); - if (aRv.Failed()) { - return nullptr; - } - - promise->CallInitFunction(aGlobal, aInit, aRv); - if (aRv.Failed()) { - return nullptr; - } - - return promise.forget(); -} - -void -Promise::CallInitFunction(const GlobalObject& aGlobal, - PromiseInit& aInit, ErrorResult& aRv) -{ - JSContext* cx = aGlobal.Context(); - - JS::Rooted<JSObject*> resolveFunc(cx, - CreateFunction(cx, this, - PromiseCallback::Resolve)); - if (!resolveFunc) { - aRv.Throw(NS_ERROR_UNEXPECTED); - return; - } - - JS::Rooted<JSObject*> rejectFunc(cx, - CreateFunction(cx, this, - PromiseCallback::Reject)); - if (!rejectFunc) { - aRv.Throw(NS_ERROR_UNEXPECTED); - return; - } - - aInit.Call(resolveFunc, rejectFunc, aRv, "promise initializer", - CallbackObject::eRethrowExceptions, Compartment()); - aRv.WouldReportJSException(); - - if (aRv.Failed()) { - if (aRv.IsUncatchableException()) { - // Just propagate this to the caller. - return; - } - - // There are two possibilities here. Either we've got a rethrown exception, - // or we reported that already and synthesized a generic NS_ERROR_FAILURE on - // the ErrorResult. In the former case, it doesn't much matter how we get - // the exception JS::Value from the ErrorResult to us, since we'll just end - // up wrapping it into the right compartment as needed if we hand it to - // someone. But in the latter case we have to ensure that the new exception - // object we create is created in our reflector compartment, not in our - // current compartment, because in the case when we're a Promise constructor - // called over Xrays creating it in the current compartment would mean - // rejecting with a value that can't be accessed by code that can call - // then() on this Promise. - // - // Luckily, MaybeReject(aRv) does exactly what we want here: it enters our - // reflector compartment before trying to produce a JS::Value from the - // ErrorResult. - MaybeReject(aRv); - } -} - -#define GET_CAPABILITIES_EXECUTOR_RESOLVE_SLOT 0 -#define GET_CAPABILITIES_EXECUTOR_REJECT_SLOT 1 - -namespace { -bool -GetCapabilitiesExecutor(JSContext* aCx, unsigned aArgc, JS::Value* aVp) -{ - // Implements - // http://www.ecma-international.org/ecma-262/6.0/#sec-getcapabilitiesexecutor-functions - // except we store the [[Resolve]] and [[Reject]] in our own internal slots, - // not in a PromiseCapability. The PromiseCapability will then read them from - // us. - JS::CallArgs args = CallArgsFromVp(aArgc, aVp); - - // Step 1 is an assert. - - // Step 2 doesn't need to be done, because it's just giving a name to the - // PromiseCapability record which is supposed to be stored in an internal - // slot. But we don't store that at all, per the comment above; we just - // directly store its [[Resolve]] and [[Reject]] members. - - // Steps 3 and 4. - if (!js::GetFunctionNativeReserved(&args.callee(), - GET_CAPABILITIES_EXECUTOR_RESOLVE_SLOT).isUndefined() || - !js::GetFunctionNativeReserved(&args.callee(), - GET_CAPABILITIES_EXECUTOR_REJECT_SLOT).isUndefined()) { - ErrorResult rv; - rv.ThrowTypeError<MSG_PROMISE_CAPABILITY_HAS_SOMETHING_ALREADY>(); - return !rv.MaybeSetPendingException(aCx); - } - - // Step 5. - js::SetFunctionNativeReserved(&args.callee(), - GET_CAPABILITIES_EXECUTOR_RESOLVE_SLOT, - args.get(0)); - - // Step 6. - js::SetFunctionNativeReserved(&args.callee(), - GET_CAPABILITIES_EXECUTOR_REJECT_SLOT, - args.get(1)); - - // Step 7. - args.rval().setUndefined(); - return true; -} -} // anonymous namespace - -/* static */ void -Promise::NewPromiseCapability(JSContext* aCx, nsIGlobalObject* aGlobal, - JS::Handle<JS::Value> aConstructor, - bool aForceCallbackCreation, - PromiseCapability& aCapability, - ErrorResult& aRv) -{ - // Implements - // http://www.ecma-international.org/ecma-262/6.0/#sec-newpromisecapability - - if (!aConstructor.isObject() || - !JS::IsConstructor(&aConstructor.toObject())) { - aRv.ThrowTypeError<MSG_ILLEGAL_PROMISE_CONSTRUCTOR>(); - return; - } - - // Step 2 is a note. - // Step 3 is already done because we got the PromiseCapability passed in. - - // Optimization: Check whether constructor is in fact the canonical - // Promise constructor for aGlobal. - JS::Rooted<JSObject*> global(aCx, aGlobal->GetGlobalJSObject()); - { - // Scope for the JSAutoCompartment, since we need to enter the compartment - // of global to get constructors from it. Save the compartment we used to - // be in, though; we'll need it later. - JS::Rooted<JSObject*> callerGlobal(aCx, JS::CurrentGlobalOrNull(aCx)); - JSAutoCompartment ac(aCx, global); - - // Now wrap aConstructor into the compartment of aGlobal, so comparing it to - // the canonical Promise for that compartment actually makes sense. - JS::Rooted<JS::Value> constructorValue(aCx, aConstructor); - if (!MaybeWrapObjectValue(aCx, &constructorValue)) { - aRv.NoteJSContextException(aCx); - return; - } - - JSObject* defaultCtor = PromiseBinding::GetConstructorObject(aCx); - if (!defaultCtor) { - aRv.NoteJSContextException(aCx); - return; - } - if (defaultCtor == &constructorValue.toObject()) { - // This is the canonical Promise constructor. - aCapability.mNativePromise = Promise::Create(aGlobal, aRv); - if (aForceCallbackCreation) { - // We have to be a bit careful here. We want to create these functions - // in the compartment in which they would be created if we actually - // invoked the constructor via JS::Construct below. That means our - // callerGlobal compartment if aConstructor is an Xray and the reflector - // compartment of the promise we're creating otherwise. But note that - // our callerGlobal compartment is precisely the reflector compartment - // unless the call was done over Xrays, because the reflector - // compartment comes from xpc::XrayAwareCalleeGlobal. So we really just - // want to create these functions in the callerGlobal compartment. - MOZ_ASSERT(xpc::WrapperFactory::IsXrayWrapper(&aConstructor.toObject()) || - callerGlobal == global); - JSAutoCompartment ac2(aCx, callerGlobal); - - JSObject* resolveFuncObj = - CreateFunction(aCx, aCapability.mNativePromise, - PromiseCallback::Resolve); - if (!resolveFuncObj) { - aRv.NoteJSContextException(aCx); - return; - } - aCapability.mResolve.setObject(*resolveFuncObj); - - JSObject* rejectFuncObj = - CreateFunction(aCx, aCapability.mNativePromise, - PromiseCallback::Reject); - if (!rejectFuncObj) { - aRv.NoteJSContextException(aCx); - return; - } - aCapability.mReject.setObject(*rejectFuncObj); - } - return; - } - } - - // Step 4. - // We can create our get-capabilities function in the calling compartment. It - // will work just as if we did |new promiseConstructor(function(a,b){}). - // Notably, if we're called over Xrays that's all fine, because we will end up - // creating the callbacks in the caller compartment in that case. - JSFunction* getCapabilitiesFunc = - js::NewFunctionWithReserved(aCx, GetCapabilitiesExecutor, - 2 /* nargs */, - 0 /* flags */, - nullptr); - if (!getCapabilitiesFunc) { - aRv.Throw(NS_ERROR_OUT_OF_MEMORY); - return; - } - - JS::Rooted<JSObject*> getCapabilitiesObj(aCx); - getCapabilitiesObj = JS_GetFunctionObject(getCapabilitiesFunc); - - // Step 5 doesn't need to be done, since we're not actually storing a - // PromiseCapability in the executor; see the comments in - // GetCapabilitiesExecutor above. - - // Step 6 and step 7. - JS::Rooted<JS::Value> getCapabilities(aCx, - JS::ObjectValue(*getCapabilitiesObj)); - JS::Rooted<JSObject*> promiseObj(aCx); - if (!JS::Construct(aCx, aConstructor, - JS::HandleValueArray(getCapabilities), - &promiseObj)) { - aRv.NoteJSContextException(aCx); - return; - } - - // Step 8 plus copying over the value to the PromiseCapability. - JS::Rooted<JS::Value> v(aCx); - v = js::GetFunctionNativeReserved(getCapabilitiesObj, - GET_CAPABILITIES_EXECUTOR_RESOLVE_SLOT); - if (!v.isObject() || !JS::IsCallable(&v.toObject())) { - aRv.ThrowTypeError<MSG_PROMISE_RESOLVE_FUNCTION_NOT_CALLABLE>(); - return; - } - aCapability.mResolve = v; - - // Step 9 plus copying over the value to the PromiseCapability. - v = js::GetFunctionNativeReserved(getCapabilitiesObj, - GET_CAPABILITIES_EXECUTOR_REJECT_SLOT); - if (!v.isObject() || !JS::IsCallable(&v.toObject())) { - aRv.ThrowTypeError<MSG_PROMISE_REJECT_FUNCTION_NOT_CALLABLE>(); - return; - } - aCapability.mReject = v; - - // Step 10. - aCapability.mPromise = promiseObj; - - // Step 11 doesn't need anything, since the PromiseCapability was passed in. -} - -/* static */ void -Promise::Resolve(const GlobalObject& aGlobal, JS::Handle<JS::Value> aThisv, - JS::Handle<JS::Value> aValue, - JS::MutableHandle<JS::Value> aRetval, ErrorResult& aRv) -{ - // Implementation of - // http://www.ecma-international.org/ecma-262/6.0/#sec-promise.resolve - - JSContext* cx = aGlobal.Context(); - - nsCOMPtr<nsIGlobalObject> global = - do_QueryInterface(aGlobal.GetAsSupports()); - if (!global) { - aRv.Throw(NS_ERROR_UNEXPECTED); - return; - } - - // Steps 1 and 2. - if (!aThisv.isObject()) { - aRv.ThrowTypeError<MSG_ILLEGAL_PROMISE_CONSTRUCTOR>(); - return; - } - - // Step 3. If a Promise was passed and matches our constructor, just return it. - if (aValue.isObject()) { - JS::Rooted<JSObject*> valueObj(cx, &aValue.toObject()); - Promise* nextPromise; - nsresult rv = UNWRAP_OBJECT(Promise, valueObj, nextPromise); - - if (NS_SUCCEEDED(rv)) { - JS::Rooted<JS::Value> constructor(cx); - if (!JS_GetProperty(cx, valueObj, "constructor", &constructor)) { - aRv.NoteJSContextException(cx); - return; - } - - // Cheat instead of calling JS_SameValue, since we know one's an object. - if (aThisv == constructor) { - aRetval.setObject(*valueObj); - return; - } - } - } - - // Step 4. - PromiseCapability capability(cx); - NewPromiseCapability(cx, global, aThisv, false, capability, aRv); - // Step 5. - if (aRv.Failed()) { - return; - } - - // Step 6. - Promise* p = capability.mNativePromise; - if (p) { - p->MaybeResolveInternal(cx, aValue); - p->mFullfillmentStack = p->mAllocationStack; - } else { - JS::Rooted<JS::Value> value(cx, aValue); - JS::Rooted<JS::Value> ignored(cx); - if (!JS::Call(cx, JS::UndefinedHandleValue /* thisVal */, - capability.mResolve, JS::HandleValueArray(value), - &ignored)) { - // Step 7. - aRv.NoteJSContextException(cx); - return; - } - } - - // Step 8. - aRetval.set(capability.PromiseValue()); -} - -/* static */ already_AddRefed<Promise> -Promise::Resolve(nsIGlobalObject* aGlobal, JSContext* aCx, - JS::Handle<JS::Value> aValue, ErrorResult& aRv) -{ - RefPtr<Promise> promise = Create(aGlobal, aRv); - if (aRv.Failed()) { - return nullptr; - } - - promise->MaybeResolveInternal(aCx, aValue); - return promise.forget(); -} - -/* static */ void -Promise::Reject(const GlobalObject& aGlobal, JS::Handle<JS::Value> aThisv, - JS::Handle<JS::Value> aValue, - JS::MutableHandle<JS::Value> aRetval, ErrorResult& aRv) -{ - // Implementation of - // http://www.ecma-international.org/ecma-262/6.0/#sec-promise.reject - - JSContext* cx = aGlobal.Context(); - - nsCOMPtr<nsIGlobalObject> global = - do_QueryInterface(aGlobal.GetAsSupports()); - if (!global) { - aRv.Throw(NS_ERROR_UNEXPECTED); - return; - } - - // Steps 1 and 2. - if (!aThisv.isObject()) { - aRv.ThrowTypeError<MSG_ILLEGAL_PROMISE_CONSTRUCTOR>(); - return; - } - - // Step 3. - PromiseCapability capability(cx); - NewPromiseCapability(cx, global, aThisv, false, capability, aRv); - // Step 4. - if (aRv.Failed()) { - return; - } - - // Step 5. - Promise* p = capability.mNativePromise; - if (p) { - p->MaybeRejectInternal(cx, aValue); - p->mRejectionStack = p->mAllocationStack; - } else { - JS::Rooted<JS::Value> value(cx, aValue); - JS::Rooted<JS::Value> ignored(cx); - if (!JS::Call(cx, JS::UndefinedHandleValue /* thisVal */, - capability.mReject, JS::HandleValueArray(value), - &ignored)) { - // Step 6. - aRv.NoteJSContextException(cx); - return; - } - } - - // Step 7. - aRetval.set(capability.PromiseValue()); -} - -/* static */ already_AddRefed<Promise> -Promise::Reject(nsIGlobalObject* aGlobal, JSContext* aCx, - JS::Handle<JS::Value> aValue, ErrorResult& aRv) -{ - RefPtr<Promise> promise = Create(aGlobal, aRv); - if (aRv.Failed()) { - return nullptr; - } - - promise->MaybeRejectInternal(aCx, aValue); - return promise.forget(); -} - -namespace { -void -SpeciesConstructor(JSContext* aCx, - JS::Handle<JSObject*> promise, - JS::Handle<JS::Value> defaultCtor, - JS::MutableHandle<JS::Value> ctor, - ErrorResult& aRv) -{ - // Implements - // http://www.ecma-international.org/ecma-262/6.0/#sec-speciesconstructor - - // Step 1. - MOZ_ASSERT(promise); - - // Step 2. - JS::Rooted<JS::Value> constructorVal(aCx); - if (!JS_GetProperty(aCx, promise, "constructor", &constructorVal)) { - // Step 3. - aRv.NoteJSContextException(aCx); - return; - } - - // Step 4. - if (constructorVal.isUndefined()) { - ctor.set(defaultCtor); - return; - } - - // Step 5. - if (!constructorVal.isObject()) { - aRv.ThrowTypeError<MSG_ILLEGAL_PROMISE_CONSTRUCTOR>(); - return; - } - - // Step 6. - JS::Rooted<jsid> species(aCx, - SYMBOL_TO_JSID(JS::GetWellKnownSymbol(aCx, JS::SymbolCode::species))); - JS::Rooted<JS::Value> speciesVal(aCx); - JS::Rooted<JSObject*> constructorObj(aCx, &constructorVal.toObject()); - if (!JS_GetPropertyById(aCx, constructorObj, species, &speciesVal)) { - // Step 7. - aRv.NoteJSContextException(aCx); - return; - } - - // Step 8. - if (speciesVal.isNullOrUndefined()) { - ctor.set(defaultCtor); - return; - } - - // Step 9. - if (speciesVal.isObject() && JS::IsConstructor(&speciesVal.toObject())) { - ctor.set(speciesVal); - return; - } - - // Step 10. - aRv.ThrowTypeError<MSG_ILLEGAL_PROMISE_CONSTRUCTOR>(); -} -} // anonymous namespace - -void -Promise::Then(JSContext* aCx, JS::Handle<JSObject*> aCalleeGlobal, - AnyCallback* aResolveCallback, AnyCallback* aRejectCallback, - JS::MutableHandle<JS::Value> aRetval, ErrorResult& aRv) -{ - NS_ASSERT_OWNINGTHREAD(Promise); - - // Implements - // http://www.ecma-international.org/ecma-262/6.0/#sec-promise.prototype.then - - // Step 1. - JS::Rooted<JS::Value> promiseVal(aCx, JS::ObjectValue(*GetWrapper())); - if (!MaybeWrapObjectValue(aCx, &promiseVal)) { - aRv.NoteJSContextException(aCx); - return; - } - JS::Rooted<JSObject*> promiseObj(aCx, &promiseVal.toObject()); - MOZ_ASSERT(promiseObj); - - // Step 2 was done by the bindings. - - // Step 3. We want to use aCalleeGlobal here because it will do the - // right thing for us via Xrays (where we won't find @@species on - // our promise constructor for now). - JS::Rooted<JS::Value> defaultCtorVal(aCx); - { // Scope for JSAutoCompartment - JSAutoCompartment ac(aCx, aCalleeGlobal); - JSObject* defaultCtor = PromiseBinding::GetConstructorObject(aCx); - if (!defaultCtor) { - aRv.NoteJSContextException(aCx); - return; - } - defaultCtorVal.setObject(*defaultCtor); - } - if (!MaybeWrapObjectValue(aCx, &defaultCtorVal)) { - aRv.NoteJSContextException(aCx); - return; - } - - JS::Rooted<JS::Value> constructor(aCx); - SpeciesConstructor(aCx, promiseObj, defaultCtorVal, &constructor, aRv); - if (aRv.Failed()) { - // Step 4. - return; - } - - // Step 5. - GlobalObject globalObj(aCx, GetWrapper()); - if (globalObj.Failed()) { - aRv.NoteJSContextException(aCx); - return; - } - nsCOMPtr<nsIGlobalObject> globalObject = - do_QueryInterface(globalObj.GetAsSupports()); - if (!globalObject) { - aRv.Throw(NS_ERROR_UNEXPECTED); - return; - } - PromiseCapability capability(aCx); - NewPromiseCapability(aCx, globalObject, constructor, false, capability, aRv); - if (aRv.Failed()) { - // Step 6. - return; - } - - // Now step 7: start - // http://www.ecma-international.org/ecma-262/6.0/#sec-performpromisethen - - // Step 1 and step 2 are just assertions. - - // Step 3 and step 4 are kinda handled for us already; we use null - // to represent "Identity" and "Thrower". - - // Steps 5 and 6. These branch based on whether we know we have a - // vanilla Promise or not. - JS::Rooted<JSObject*> global(aCx, JS::CurrentGlobalOrNull(aCx)); - if (capability.mNativePromise) { - Promise* promise = capability.mNativePromise; - - RefPtr<PromiseCallback> resolveCb = - PromiseCallback::Factory(promise, global, aResolveCallback, - PromiseCallback::Resolve); - - RefPtr<PromiseCallback> rejectCb = - PromiseCallback::Factory(promise, global, aRejectCallback, - PromiseCallback::Reject); - - AppendCallbacks(resolveCb, rejectCb); - } else { - JS::Rooted<JSObject*> resolveObj(aCx, &capability.mResolve.toObject()); - RefPtr<AnyCallback> resolveFunc = - new AnyCallback(aCx, resolveObj, GetIncumbentGlobal()); - - JS::Rooted<JSObject*> rejectObj(aCx, &capability.mReject.toObject()); - RefPtr<AnyCallback> rejectFunc = - new AnyCallback(aCx, rejectObj, GetIncumbentGlobal()); - - if (!capability.mPromise) { - aRv.ThrowTypeError<MSG_ILLEGAL_PROMISE_CONSTRUCTOR>(); - return; - } - JS::Rooted<JSObject*> newPromiseObj(aCx, capability.mPromise); - // We want to store the reflector itself. - newPromiseObj = js::CheckedUnwrap(newPromiseObj); - if (!newPromiseObj) { - // Just throw something. - aRv.ThrowTypeError<MSG_ILLEGAL_PROMISE_CONSTRUCTOR>(); - return; - } - - RefPtr<PromiseCallback> resolveCb; - if (aResolveCallback) { - resolveCb = new WrapperPromiseCallback(global, aResolveCallback, - newPromiseObj, - resolveFunc, rejectFunc); - } else { - resolveCb = new InvokePromiseFuncCallback(global, newPromiseObj, - resolveFunc); - } - - RefPtr<PromiseCallback> rejectCb; - if (aRejectCallback) { - rejectCb = new WrapperPromiseCallback(global, aRejectCallback, - newPromiseObj, - resolveFunc, rejectFunc); - } else { - rejectCb = new InvokePromiseFuncCallback(global, newPromiseObj, - rejectFunc); - } - - AppendCallbacks(resolveCb, rejectCb); - } - - aRetval.set(capability.PromiseValue()); -} - -void -Promise::Catch(JSContext* aCx, AnyCallback* aRejectCallback, - JS::MutableHandle<JS::Value> aRetval, - ErrorResult& aRv) -{ - NS_ASSERT_OWNINGTHREAD(Promise); - - // Implements - // http://www.ecma-international.org/ecma-262/6.0/#sec-promise.prototype.catch - - // We can't call Promise::Then directly, because someone might have - // overridden Promise.prototype.then. - JS::Rooted<JS::Value> promiseVal(aCx, JS::ObjectValue(*GetWrapper())); - if (!MaybeWrapObjectValue(aCx, &promiseVal)) { - aRv.NoteJSContextException(aCx); - return; - } - JS::Rooted<JSObject*> promiseObj(aCx, &promiseVal.toObject()); - MOZ_ASSERT(promiseObj); - JS::AutoValueArray<2> callbacks(aCx); - callbacks[0].setUndefined(); - if (aRejectCallback) { - callbacks[1].setObject(*aRejectCallback->Callable()); - // It could be in any compartment, so put it in ours. - if (!MaybeWrapObjectValue(aCx, callbacks[1])) { - aRv.NoteJSContextException(aCx); - return; - } - } else { - callbacks[1].setNull(); - } - if (!JS_CallFunctionName(aCx, promiseObj, "then", callbacks, aRetval)) { - aRv.NoteJSContextException(aCx); - } -} - -/** - * The CountdownHolder class encapsulates Promise.all countdown functions and - * the countdown holder parts of the Promises spec. It maintains the result - * array and AllResolveElementFunctions use SetValue() to set the array indices. - */ -class CountdownHolder final : public nsISupports -{ -public: - NS_DECL_CYCLE_COLLECTING_ISUPPORTS - NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS(CountdownHolder) - - CountdownHolder(const GlobalObject& aGlobal, Promise* aPromise, - uint32_t aCountdown) - : mPromise(aPromise), mCountdown(aCountdown) - { - MOZ_ASSERT(aCountdown != 0); - JSContext* cx = aGlobal.Context(); - - // The only time aGlobal.Context() and aGlobal.Get() are not - // same-compartment is when we're called via Xrays, and in that situation we - // in fact want to create the array in the callee compartment - - JSAutoCompartment ac(cx, aGlobal.Get()); - mValues = JS_NewArrayObject(cx, aCountdown); - mozilla::HoldJSObjects(this); - } - -private: - ~CountdownHolder() - { - mozilla::DropJSObjects(this); - } - -public: - void SetValue(uint32_t index, const JS::Handle<JS::Value> aValue) - { - MOZ_ASSERT(mCountdown > 0); - - AutoJSAPI jsapi; - if (!jsapi.Init(mValues)) { - return; - } - JSContext* cx = jsapi.cx(); - - JS::Rooted<JS::Value> value(cx, aValue); - JS::Rooted<JSObject*> values(cx, mValues); - if (!JS_WrapValue(cx, &value) || - !JS_DefineElement(cx, values, index, value, JSPROP_ENUMERATE)) { - MOZ_ASSERT(JS_IsExceptionPending(cx)); - JS::Rooted<JS::Value> exn(cx); - if (!jsapi.StealException(&exn)) { - mPromise->MaybeReject(NS_ERROR_OUT_OF_MEMORY); - } else { - mPromise->MaybeReject(cx, exn); - } - } - - --mCountdown; - if (mCountdown == 0) { - JS::Rooted<JS::Value> result(cx, JS::ObjectValue(*mValues)); - mPromise->MaybeResolve(cx, result); - } - } - -private: - RefPtr<Promise> mPromise; - uint32_t mCountdown; - JS::Heap<JSObject*> mValues; -}; - -NS_IMPL_CYCLE_COLLECTING_ADDREF(CountdownHolder) -NS_IMPL_CYCLE_COLLECTING_RELEASE(CountdownHolder) -NS_IMPL_CYCLE_COLLECTION_CLASS(CountdownHolder) - -NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(CountdownHolder) - NS_INTERFACE_MAP_ENTRY(nsISupports) -NS_INTERFACE_MAP_END - -NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN(CountdownHolder) - NS_IMPL_CYCLE_COLLECTION_TRACE_JS_MEMBER_CALLBACK(mValues) -NS_IMPL_CYCLE_COLLECTION_TRACE_END - -NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(CountdownHolder) - NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mPromise) -NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END - -NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(CountdownHolder) - NS_IMPL_CYCLE_COLLECTION_UNLINK(mPromise) - tmp->mValues = nullptr; -NS_IMPL_CYCLE_COLLECTION_UNLINK_END - -/** - * An AllResolveElementFunction is the per-promise - * part of the Promise.all() algorithm. - * Every Promise in the handler is handed an instance of this as a resolution - * handler and it sets the relevant index in the CountdownHolder. - */ -class AllResolveElementFunction final : public PromiseNativeHandler -{ -public: - NS_DECL_CYCLE_COLLECTING_ISUPPORTS - NS_DECL_CYCLE_COLLECTION_CLASS(AllResolveElementFunction) - - AllResolveElementFunction(CountdownHolder* aHolder, uint32_t aIndex) - : mCountdownHolder(aHolder), mIndex(aIndex) - { - MOZ_ASSERT(aHolder); - } - - void - ResolvedCallback(JSContext* aCx, JS::Handle<JS::Value> aValue) override - { - mCountdownHolder->SetValue(mIndex, aValue); - } - - void - RejectedCallback(JSContext* aCx, JS::Handle<JS::Value> aValue) override - { - // Should never be attached to Promise as a reject handler. - MOZ_CRASH("AllResolveElementFunction should never be attached to a Promise's reject handler!"); - } - -private: - ~AllResolveElementFunction() - { - } - - RefPtr<CountdownHolder> mCountdownHolder; - uint32_t mIndex; -}; - -NS_IMPL_CYCLE_COLLECTING_ADDREF(AllResolveElementFunction) -NS_IMPL_CYCLE_COLLECTING_RELEASE(AllResolveElementFunction) - -NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(AllResolveElementFunction) - NS_INTERFACE_MAP_ENTRY(nsISupports) -NS_INTERFACE_MAP_END - -NS_IMPL_CYCLE_COLLECTION(AllResolveElementFunction, mCountdownHolder) - -static const JSClass PromiseAllDataHolderClass = { - "PromiseAllDataHolder", JSCLASS_HAS_RESERVED_SLOTS(3) -}; - -// Slot indices for objects of class PromiseAllDataHolderClass. -#define DATA_HOLDER_REMAINING_ELEMENTS_SLOT 0 -#define DATA_HOLDER_VALUES_ARRAY_SLOT 1 -#define DATA_HOLDER_RESOLVE_FUNCTION_SLOT 2 - -// Slot indices for PromiseAllResolveElement. -// The RESOLVE_ELEMENT_INDEX_SLOT stores our index unless we've already been -// called. Then it stores INT32_MIN (which is never a valid index value). -#define RESOLVE_ELEMENT_INDEX_SLOT 0 -// The RESOLVE_ELEMENT_DATA_HOLDER_SLOT slot stores an object of class -// PromiseAllDataHolderClass. -#define RESOLVE_ELEMENT_DATA_HOLDER_SLOT 1 - -static bool -PromiseAllResolveElement(JSContext* aCx, unsigned aArgc, JS::Value* aVp) -{ - // Implements - // http://www.ecma-international.org/ecma-262/6.0/#sec-promise.all-resolve-element-functions - // - // See the big comment about compartments in Promise::All "Substep 4" that - // explains what compartments the various stuff here lives in. - JS::CallArgs args = CallArgsFromVp(aArgc, aVp); - - // Step 1. - int32_t index = - js::GetFunctionNativeReserved(&args.callee(), - RESOLVE_ELEMENT_INDEX_SLOT).toInt32(); - // Step 2. - if (index == INT32_MIN) { - args.rval().setUndefined(); - return true; - } - - // Step 3. - js::SetFunctionNativeReserved(&args.callee(), - RESOLVE_ELEMENT_INDEX_SLOT, - JS::Int32Value(INT32_MIN)); - - // Step 4 already done. - - // Step 5. - JS::Rooted<JSObject*> dataHolder(aCx, - &js::GetFunctionNativeReserved(&args.callee(), - RESOLVE_ELEMENT_DATA_HOLDER_SLOT).toObject()); - - JS::Rooted<JS::Value> values(aCx, - js::GetReservedSlot(dataHolder, DATA_HOLDER_VALUES_ARRAY_SLOT)); - - // Step 6, effectively. - JS::Rooted<JS::Value> resolveFunc(aCx, - js::GetReservedSlot(dataHolder, DATA_HOLDER_RESOLVE_FUNCTION_SLOT)); - - // Step 7. - int32_t remainingElements = - js::GetReservedSlot(dataHolder, DATA_HOLDER_REMAINING_ELEMENTS_SLOT).toInt32(); - - // Step 8. - JS::Rooted<JSObject*> valuesObj(aCx, &values.toObject()); - if (!JS_DefineElement(aCx, valuesObj, index, args.get(0), JSPROP_ENUMERATE)) { - return false; - } - - // Step 9. - remainingElements -= 1; - js::SetReservedSlot(dataHolder, DATA_HOLDER_REMAINING_ELEMENTS_SLOT, - JS::Int32Value(remainingElements)); - - // Step 10. - if (remainingElements == 0) { - return JS::Call(aCx, JS::UndefinedHandleValue, resolveFunc, - JS::HandleValueArray(values), args.rval()); - } - - // Step 11. - args.rval().setUndefined(); - return true; -} - - -/* static */ void -Promise::All(const GlobalObject& aGlobal, JS::Handle<JS::Value> aThisv, - JS::Handle<JS::Value> aIterable, - JS::MutableHandle<JS::Value> aRetval, ErrorResult& aRv) -{ - // Implements http://www.ecma-international.org/ecma-262/6.0/#sec-promise.all - nsCOMPtr<nsIGlobalObject> global = - do_QueryInterface(aGlobal.GetAsSupports()); - if (!global) { - aRv.Throw(NS_ERROR_UNEXPECTED); - return; - } - - JSContext* cx = aGlobal.Context(); - - // Steps 1-5: nothing to do. Note that the @@species bits got removed in - // https://github.com/tc39/ecma262/pull/211 - - // Step 6. - PromiseCapability capability(cx); - NewPromiseCapability(cx, global, aThisv, true, capability, aRv); - // Step 7. - if (aRv.Failed()) { - return; - } - - MOZ_ASSERT(aThisv.isObject(), "How did NewPromiseCapability succeed?"); - JS::Rooted<JSObject*> constructorObj(cx, &aThisv.toObject()); - - // After this point we have a useful promise value in "capability", so just go - // ahead and put it in our retval now. Every single return path below would - // want to do that anyway. - aRetval.set(capability.PromiseValue()); - if (!MaybeWrapValue(cx, aRetval)) { - aRv.NoteJSContextException(cx); - return; - } - - // The arguments we're going to be passing to "then" on each loop iteration. - // The second one we know already; the first one will be created on each - // iteration of the loop. - JS::AutoValueArray<2> callbackFunctions(cx); - callbackFunctions[1].set(capability.mReject); - - // Steps 8 and 9. - JS::ForOfIterator iter(cx); - if (!iter.init(aIterable, JS::ForOfIterator::AllowNonIterable)) { - capability.RejectWithException(cx, aRv); - return; - } - - if (!iter.valueIsIterable()) { - ThrowErrorMessage(cx, MSG_PROMISE_ARG_NOT_ITERABLE, - "Argument of Promise.all"); - capability.RejectWithException(cx, aRv); - return; - } - - // Step 10 doesn't need to be done, because ForOfIterator handles it - // for us. - - // Now we jump over to - // http://www.ecma-international.org/ecma-262/6.0/#sec-performpromiseall - // and do its steps. - - // Substep 4. Create our data holder that holds all the things shared across - // every step of the iterator. In particular, this holds the - // remainingElementsCount (as an integer reserved slot), the array of values, - // and the resolve function from our PromiseCapability. - // - // We have to be very careful about which compartments we create things in - // here. In particular, we have to maintain the invariant that anything - // stored in a reserved slot is same-compartment with the object whose - // reserved slot it's in. But we want to create the values array in the - // Promise reflector compartment, because that array can get exposed to code - // that has access to the Promise reflector (in particular code from that - // compartment), and that should work, even if the Promise reflector - // compartment is less-privileged than our caller compartment. - // - // So the plan is as follows: Create the values array in the promise reflector - // compartment. Create the PromiseAllResolveElement function and the data - // holder in our current compartment. Store a cross-compartment wrapper to - // the values array in the holder. This should be OK because the only things - // we hand the PromiseAllResolveElement function to are the "then" calls we do - // and in the case when the reflector compartment is not the current - // compartment those are happening over Xrays anyway, which means they get the - // canonical "then" function and content can't see our - // PromiseAllResolveElement. - JS::Rooted<JSObject*> dataHolder(cx); - dataHolder = JS_NewObjectWithGivenProto(cx, &PromiseAllDataHolderClass, - nullptr); - if (!dataHolder) { - capability.RejectWithException(cx, aRv); - return; - } - - JS::Rooted<JSObject*> reflectorGlobal(cx, global->GetGlobalJSObject()); - JS::Rooted<JSObject*> valuesArray(cx); - { // Scope for JSAutoCompartment. - JSAutoCompartment ac(cx, reflectorGlobal); - valuesArray = JS_NewArrayObject(cx, 0); - } - if (!valuesArray) { - // It's important that we've exited the JSAutoCompartment by now, before - // calling RejectWithException and possibly invoking capability.mReject. - capability.RejectWithException(cx, aRv); - return; - } - - // The values array as a value we can pass to a function in our current - // compartment, or store in the holder's reserved slot. - JS::Rooted<JS::Value> valuesArrayVal(cx, JS::ObjectValue(*valuesArray)); - if (!MaybeWrapObjectValue(cx, &valuesArrayVal)) { - capability.RejectWithException(cx, aRv); - return; - } - - js::SetReservedSlot(dataHolder, DATA_HOLDER_REMAINING_ELEMENTS_SLOT, - JS::Int32Value(1)); - js::SetReservedSlot(dataHolder, DATA_HOLDER_VALUES_ARRAY_SLOT, - valuesArrayVal); - js::SetReservedSlot(dataHolder, DATA_HOLDER_RESOLVE_FUNCTION_SLOT, - capability.mResolve); - - // Substep 5. - CheckedInt32 index = 0; - - // Substep 6. - JS::Rooted<JS::Value> nextValue(cx); - while (true) { - bool done; - // Steps a, b, c, e, f, g. - if (!iter.next(&nextValue, &done)) { - capability.RejectWithException(cx, aRv); - return; - } - - // Step d. - if (done) { - int32_t remainingCount = - js::GetReservedSlot(dataHolder, - DATA_HOLDER_REMAINING_ELEMENTS_SLOT).toInt32(); - remainingCount -= 1; - if (remainingCount == 0) { - JS::Rooted<JS::Value> ignored(cx); - if (!JS::Call(cx, JS::UndefinedHandleValue, capability.mResolve, - JS::HandleValueArray(valuesArrayVal), &ignored)) { - capability.RejectWithException(cx, aRv); - } - return; - } - js::SetReservedSlot(dataHolder, DATA_HOLDER_REMAINING_ELEMENTS_SLOT, - JS::Int32Value(remainingCount)); - // We're all set for now! - return; - } - - // Step h. - { // Scope for the JSAutoCompartment we need to work with valuesArray. We - // mostly do this for performance; we could go ahead and do the define via - // a cross-compartment proxy instead... - JSAutoCompartment ac(cx, valuesArray); - if (!JS_DefineElement(cx, valuesArray, index.value(), - JS::UndefinedHandleValue, JSPROP_ENUMERATE)) { - // Have to go back into the caller compartment before we try to touch - // capability.mReject. Luckily, capability.mReject is guaranteed to be - // an object in the right compartment here. - JSAutoCompartment ac2(cx, &capability.mReject.toObject()); - capability.RejectWithException(cx, aRv); - return; - } - } - - // Step i. Sadly, we can't take a shortcut here even if - // capability.mNativePromise exists, because someone could have overridden - // "resolve" on the canonical Promise constructor. - JS::Rooted<JS::Value> nextPromise(cx); - if (!JS_CallFunctionName(cx, constructorObj, "resolve", - JS::HandleValueArray(nextValue), - &nextPromise)) { - // Step j. - capability.RejectWithException(cx, aRv); - return; - } - - // Step k. - JS::Rooted<JSObject*> resolveElement(cx); - JSFunction* resolveFunc = - js::NewFunctionWithReserved(cx, PromiseAllResolveElement, - 1 /* nargs */, 0 /* flags */, nullptr); - if (!resolveFunc) { - capability.RejectWithException(cx, aRv); - return; - } - - resolveElement = JS_GetFunctionObject(resolveFunc); - // Steps l-p. - js::SetFunctionNativeReserved(resolveElement, - RESOLVE_ELEMENT_INDEX_SLOT, - JS::Int32Value(index.value())); - js::SetFunctionNativeReserved(resolveElement, - RESOLVE_ELEMENT_DATA_HOLDER_SLOT, - JS::ObjectValue(*dataHolder)); - - // Step q. - int32_t remainingElements = - js::GetReservedSlot(dataHolder, DATA_HOLDER_REMAINING_ELEMENTS_SLOT).toInt32(); - js::SetReservedSlot(dataHolder, DATA_HOLDER_REMAINING_ELEMENTS_SLOT, - JS::Int32Value(remainingElements + 1)); - - // Step r. And now we don't know whether nextPromise has an overridden - // "then" method, so no shortcuts here either. - callbackFunctions[0].setObject(*resolveElement); - JS::Rooted<JSObject*> nextPromiseObj(cx); - JS::Rooted<JS::Value> ignored(cx); - if (!JS_ValueToObject(cx, nextPromise, &nextPromiseObj) || - !JS_CallFunctionName(cx, nextPromiseObj, "then", callbackFunctions, - &ignored)) { - // Step s. - capability.RejectWithException(cx, aRv); - } - - // Step t. - index += 1; - if (!index.isValid()) { - // Let's just claim OOM. - aRv.Throw(NS_ERROR_OUT_OF_MEMORY); - capability.RejectWithException(cx, aRv); - } - } -} - -/* static */ already_AddRefed<Promise> -Promise::All(const GlobalObject& aGlobal, - const nsTArray<RefPtr<Promise>>& aPromiseList, ErrorResult& aRv) -{ - nsCOMPtr<nsIGlobalObject> global = - do_QueryInterface(aGlobal.GetAsSupports()); - if (!global) { - aRv.Throw(NS_ERROR_UNEXPECTED); - return nullptr; - } - - JSContext* cx = aGlobal.Context(); - - if (aPromiseList.IsEmpty()) { - JS::Rooted<JSObject*> empty(cx, JS_NewArrayObject(cx, 0)); - if (!empty) { - aRv.Throw(NS_ERROR_OUT_OF_MEMORY); - return nullptr; - } - JS::Rooted<JS::Value> value(cx, JS::ObjectValue(*empty)); - // We know "value" is not a promise, so call the Resolve function - // that doesn't have to check for that. - return Promise::Resolve(global, cx, value, aRv); - } - - RefPtr<Promise> promise = Create(global, aRv); - if (aRv.Failed()) { - return nullptr; - } - RefPtr<CountdownHolder> holder = - new CountdownHolder(aGlobal, promise, aPromiseList.Length()); - - JS::Rooted<JSObject*> obj(cx, JS::CurrentGlobalOrNull(cx)); - if (!obj) { - aRv.Throw(NS_ERROR_UNEXPECTED); - return nullptr; - } - - RefPtr<PromiseCallback> rejectCb = new RejectPromiseCallback(promise, obj); - - for (uint32_t i = 0; i < aPromiseList.Length(); ++i) { - RefPtr<PromiseNativeHandler> resolveHandler = - new AllResolveElementFunction(holder, i); - - RefPtr<PromiseCallback> resolveCb = - new NativePromiseCallback(resolveHandler, Resolved); - - // Every promise gets its own resolve callback, which will set the right - // index in the array to the resolution value. - aPromiseList[i]->AppendCallbacks(resolveCb, rejectCb); - } - - return promise.forget(); -} - -/* static */ void -Promise::Race(const GlobalObject& aGlobal, JS::Handle<JS::Value> aThisv, - JS::Handle<JS::Value> aIterable, JS::MutableHandle<JS::Value> aRetval, - ErrorResult& aRv) -{ - // Implements http://www.ecma-international.org/ecma-262/6.0/#sec-promise.race - nsCOMPtr<nsIGlobalObject> global = - do_QueryInterface(aGlobal.GetAsSupports()); - if (!global) { - aRv.Throw(NS_ERROR_UNEXPECTED); - return; - } - - JSContext* cx = aGlobal.Context(); - - // Steps 1-5: nothing to do. Note that the @@species bits got removed in - // https://github.com/tc39/ecma262/pull/211 - PromiseCapability capability(cx); - - // Step 6. - NewPromiseCapability(cx, global, aThisv, true, capability, aRv); - // Step 7. - if (aRv.Failed()) { - return; - } - - MOZ_ASSERT(aThisv.isObject(), "How did NewPromiseCapability succeed?"); - JS::Rooted<JSObject*> constructorObj(cx, &aThisv.toObject()); - - // After this point we have a useful promise value in "capability", so just go - // ahead and put it in our retval now. Every single return path below would - // want to do that anyway. - aRetval.set(capability.PromiseValue()); - if (!MaybeWrapValue(cx, aRetval)) { - aRv.NoteJSContextException(cx); - return; - } - - // The arguments we're going to be passing to "then" on each loop iteration. - JS::AutoValueArray<2> callbackFunctions(cx); - callbackFunctions[0].set(capability.mResolve); - callbackFunctions[1].set(capability.mReject); - - // Steps 8 and 9. - JS::ForOfIterator iter(cx); - if (!iter.init(aIterable, JS::ForOfIterator::AllowNonIterable)) { - capability.RejectWithException(cx, aRv); - return; - } - - if (!iter.valueIsIterable()) { - ThrowErrorMessage(cx, MSG_PROMISE_ARG_NOT_ITERABLE, - "Argument of Promise.race"); - capability.RejectWithException(cx, aRv); - return; - } - - // Step 10 doesn't need to be done, because ForOfIterator handles it - // for us. - - // Now we jump over to - // http://www.ecma-international.org/ecma-262/6.0/#sec-performpromiserace - // and do its steps. - JS::Rooted<JS::Value> nextValue(cx); - while (true) { - bool done; - // Steps a, b, c, e, f, g. - if (!iter.next(&nextValue, &done)) { - capability.RejectWithException(cx, aRv); - return; - } - - // Step d. - if (done) { - // We're all set! - return; - } - - // Step h. Sadly, we can't take a shortcut here even if - // capability.mNativePromise exists, because someone could have overridden - // "resolve" on the canonical Promise constructor. - JS::Rooted<JS::Value> nextPromise(cx); - if (!JS_CallFunctionName(cx, constructorObj, "resolve", - JS::HandleValueArray(nextValue), &nextPromise)) { - // Step i. - capability.RejectWithException(cx, aRv); - return; - } - - // Step j. And now we don't know whether nextPromise has an overridden - // "then" method, so no shortcuts here either. - JS::Rooted<JSObject*> nextPromiseObj(cx); - JS::Rooted<JS::Value> ignored(cx); - if (!JS_ValueToObject(cx, nextPromise, &nextPromiseObj) || - !JS_CallFunctionName(cx, nextPromiseObj, "then", callbackFunctions, - &ignored)) { - // Step k. - capability.RejectWithException(cx, aRv); - } - } -} - -/* static */ -bool -Promise::PromiseSpecies(JSContext* aCx, unsigned aArgc, JS::Value* aVp) -{ - JS::CallArgs args = CallArgsFromVp(aArgc, aVp); - args.rval().set(args.thisv()); - return true; -} - -void -Promise::AppendNativeHandler(PromiseNativeHandler* aRunnable) -{ - NS_ASSERT_OWNINGTHREAD(Promise); - - RefPtr<PromiseCallback> resolveCb = - new NativePromiseCallback(aRunnable, Resolved); - - RefPtr<PromiseCallback> rejectCb = - new NativePromiseCallback(aRunnable, Rejected); - - AppendCallbacks(resolveCb, rejectCb); -} - -#endif // SPIDERMONKEY_PROMISE - JSObject* Promise::GlobalJSObject() const { @@ -2560,382 +644,6 @@ Promise::Compartment() const return js::GetObjectCompartment(GlobalJSObject()); } -#ifndef SPIDERMONKEY_PROMISE -void -Promise::AppendCallbacks(PromiseCallback* aResolveCallback, - PromiseCallback* aRejectCallback) -{ - if (!mGlobal || mGlobal->IsDying()) { - return; - } - - MOZ_ASSERT(aResolveCallback); - MOZ_ASSERT(aRejectCallback); - - if (mIsLastInChain && mState == PromiseState::Rejected) { - // This rejection is now consumed. - PromiseDebugging::AddConsumedRejection(*this); - // Note that we may not have had the opportunity to call - // RunResolveTask() yet, so we may never have called - // `PromiseDebugging:AddUncaughtRejection`. - } - mIsLastInChain = false; - -#if defined(DOM_PROMISE_DEPRECATED_REPORTING) - // Now that there is a callback, we don't need to report anymore. - mHadRejectCallback = true; - RemoveWorkerHolder(); -#endif // defined(DOM_PROMISE_DEPRECATED_REPORTING) - - mResolveCallbacks.AppendElement(aResolveCallback); - mRejectCallbacks.AppendElement(aRejectCallback); - - // If promise's state is fulfilled, queue a task to process our fulfill - // callbacks with promise's result. If promise's state is rejected, queue a - // task to process our reject callbacks with promise's result. - if (mState != Pending) { - TriggerPromiseReactions(); - } -} -#endif // SPIDERMONKEY_PROMISE - -#ifndef SPIDERMONKEY_PROMISE -#if defined(DOM_PROMISE_DEPRECATED_REPORTING) -void -Promise::MaybeReportRejected() -{ - NS_ASSERT_OWNINGTHREAD(Promise); - - if (mState != Rejected || mHadRejectCallback || mResult.isUndefined()) { - return; - } - - AutoJSAPI jsapi; - // We may not have a usable global by now (if it got unlinked - // already), so don't init with it. - jsapi.Init(); - JSContext* cx = jsapi.cx(); - JS::Rooted<JSObject*> obj(cx, GetWrapper()); - MOZ_ASSERT(obj); // We preserve our wrapper, so should always have one here. - JS::Rooted<JS::Value> val(cx, mResult); - - JSAutoCompartment ac(cx, obj); - if (!JS_WrapValue(cx, &val)) { - JS_ClearPendingException(cx); - return; - } - - js::ErrorReport report(cx); - RefPtr<Exception> exp; - bool isObject = val.isObject(); - if (!isObject || NS_FAILED(UNWRAP_OBJECT(Exception, &val.toObject(), exp))) { - if (!isObject || - NS_FAILED(UNWRAP_OBJECT(DOMException, &val.toObject(), exp))) { - if (!report.init(cx, val, js::ErrorReport::NoSideEffects)) { - NS_WARNING("Couldn't convert the unhandled rejected value to an exception."); - JS_ClearPendingException(cx); - return; - } - } - } - - RefPtr<xpc::ErrorReport> xpcReport = new xpc::ErrorReport(); - bool isMainThread = MOZ_LIKELY(NS_IsMainThread()); - bool isChrome = isMainThread ? nsContentUtils::IsSystemPrincipal(nsContentUtils::ObjectPrincipal(obj)) - : GetCurrentThreadWorkerPrivate()->IsChromeWorker(); - nsGlobalWindow* win = isMainThread ? xpc::WindowGlobalOrNull(obj) : nullptr; - uint64_t windowID = win ? win->AsInner()->WindowID() : 0; - if (exp) { - xpcReport->Init(cx, exp, isChrome, windowID); - } else { - xpcReport->Init(report.report(), report.toStringResult(), - isChrome, windowID); - } - - // Now post an event to do the real reporting async - // Since Promises preserve their wrapper, it is essential to RefPtr<> the - // AsyncErrorReporter, otherwise if the call to DispatchToMainThread fails, it - // will leak. See Bug 958684. So... don't use DispatchToMainThread() - nsCOMPtr<nsIThread> mainThread = do_GetMainThread(); - if (NS_WARN_IF(!mainThread)) { - // Would prefer NS_ASSERTION, but that causes failure in xpcshell tests - NS_WARNING("!!! Trying to report rejected Promise after MainThread shutdown"); - } - if (mainThread) { - RefPtr<AsyncErrorReporter> r = new AsyncErrorReporter(xpcReport); - mainThread->Dispatch(r.forget(), NS_DISPATCH_NORMAL); - } -} -#endif // defined(DOM_PROMISE_DEPRECATED_REPORTING) - -void -Promise::MaybeResolveInternal(JSContext* aCx, - JS::Handle<JS::Value> aValue) -{ - NS_ASSERT_OWNINGTHREAD(Promise); - - if (mResolvePending) { - return; - } - - ResolveInternal(aCx, aValue); -} - -void -Promise::MaybeRejectInternal(JSContext* aCx, - JS::Handle<JS::Value> aValue) -{ - NS_ASSERT_OWNINGTHREAD(Promise); - - if (mResolvePending) { - return; - } - - RejectInternal(aCx, aValue); -} - -void -Promise::HandleException(JSContext* aCx) -{ - NS_ASSERT_OWNINGTHREAD(Promise); - - JS::Rooted<JS::Value> exn(aCx); - if (JS_GetPendingException(aCx, &exn)) { - JS_ClearPendingException(aCx); - RejectInternal(aCx, exn); - } -} - -void -Promise::ResolveInternal(JSContext* aCx, - JS::Handle<JS::Value> aValue) -{ - NS_ASSERT_OWNINGTHREAD(Promise); - - CycleCollectedJSContext* context = CycleCollectedJSContext::Get(); - - mResolvePending = true; - - if (aValue.isObject()) { - JS::Rooted<JSObject*> valueObj(aCx, &aValue.toObject()); - - // Thenables. - JS::Rooted<JS::Value> then(aCx); - if (!JS_GetProperty(aCx, valueObj, "then", &then)) { - HandleException(aCx); - return; - } - - if (then.isObject() && JS::IsCallable(&then.toObject())) { - // This is the then() function of the thenable aValueObj. - JS::Rooted<JSObject*> thenObj(aCx, &then.toObject()); - - // We used to have a fast path here for the case when the following - // requirements held: - // - // 1) valueObj is a Promise. - // 2) thenObj is a JSFunction backed by our actual Promise::Then - // implementation. - // - // But now that we're doing subclassing in Promise.prototype.then we would - // also need the following requirements: - // - // 3) Getting valueObj.constructor has no side-effects. - // 4) Getting valueObj.constructor[@@species] has no side-effects. - // 5) valueObj.constructor[@@species] is a function and calling it has no - // side-effects (e.g. it's the canonical Promise constructor) and it - // provides some callback functions to call as arguments to its - // argument. - // - // Ensuring that stuff while not inside SpiderMonkey is painful, so let's - // drop the fast path for now. - - RefPtr<PromiseInit> thenCallback = - new PromiseInit(nullptr, thenObj, mozilla::dom::GetIncumbentGlobal()); - RefPtr<PromiseResolveThenableJob> task = - new PromiseResolveThenableJob(this, valueObj, thenCallback); - context->DispatchToMicroTask(task.forget()); - return; - } - } - - MaybeSettle(aValue, Resolved); -} - -void -Promise::RejectInternal(JSContext* aCx, - JS::Handle<JS::Value> aValue) -{ - NS_ASSERT_OWNINGTHREAD(Promise); - - mResolvePending = true; - - MaybeSettle(aValue, Rejected); -} - -void -Promise::Settle(JS::Handle<JS::Value> aValue, PromiseState aState) -{ - MOZ_ASSERT(mGlobal, - "We really should have a global here. Except we sometimes don't " - "in the wild for some odd reason"); - NS_ASSERT_OWNINGTHREAD(Promise); - - if (!mGlobal || mGlobal->IsDying()) { - return; - } - - mSettlementTimestamp = TimeStamp::Now(); - - AutoJSAPI jsapi; - jsapi.Init(); - JSContext* cx = jsapi.cx(); - JS::RootedObject wrapper(cx, GetWrapper()); - MOZ_ASSERT(wrapper); // We preserved it - JSAutoCompartment ac(cx, wrapper); - - JS::Rooted<JS::Value> value(cx, aValue); - - if (!JS_WrapValue(cx, &value)) { - JS_ClearPendingException(cx); - value = JS::UndefinedValue(); - } - SetResult(value); - SetState(aState); - - JS::dbg::onPromiseSettled(cx, wrapper); - - if (aState == PromiseState::Rejected && - mIsLastInChain) { - // The Promise has just been rejected, and it is last in chain. - // We need to inform PromiseDebugging. - // If the Promise is eventually not the last in chain anymore, - // we will need to inform PromiseDebugging again. - PromiseDebugging::AddUncaughtRejection(*this); - } - -#if defined(DOM_PROMISE_DEPRECATED_REPORTING) - // If the Promise was rejected, and there is no reject handler already setup, - // watch for thread shutdown. - if (aState == PromiseState::Rejected && - !mHadRejectCallback && - !NS_IsMainThread()) { - WorkerPrivate* worker = GetCurrentThreadWorkerPrivate(); - MOZ_ASSERT(worker); - worker->AssertIsOnWorkerThread(); - - mWorkerHolder = new PromiseReportRejectWorkerHolder(this); - if (NS_WARN_IF(!mWorkerHolder->HoldWorker(worker, Closing))) { - mWorkerHolder = nullptr; - // Worker is shutting down, report rejection immediately since it is - // unlikely that reject callbacks will be added after this point. - MaybeReportRejectedOnce(); - } - } -#endif // defined(DOM_PROMISE_DEPRECATED_REPORTING) - - TriggerPromiseReactions(); -} - -void -Promise::MaybeSettle(JS::Handle<JS::Value> aValue, - PromiseState aState) -{ - NS_ASSERT_OWNINGTHREAD(Promise); - - // Promise.all() or Promise.race() implementations will repeatedly call - // Resolve/RejectInternal rather than using the Maybe... forms. Stop SetState - // from asserting. - if (mState != Pending) { - return; - } - - Settle(aValue, aState); -} - -void -Promise::TriggerPromiseReactions() -{ - NS_ASSERT_OWNINGTHREAD(Promise); - - CycleCollectedJSContext* runtime = CycleCollectedJSContext::Get(); - - nsTArray<RefPtr<PromiseCallback>> callbacks; - callbacks.SwapElements(mState == Resolved ? mResolveCallbacks - : mRejectCallbacks); - mResolveCallbacks.Clear(); - mRejectCallbacks.Clear(); - - for (uint32_t i = 0; i < callbacks.Length(); ++i) { - RefPtr<PromiseReactionJob> task = - new PromiseReactionJob(this, callbacks[i], mResult); - runtime->DispatchToMicroTask(task.forget()); - } -} - -#if defined(DOM_PROMISE_DEPRECATED_REPORTING) -void -Promise::RemoveWorkerHolder() -{ - NS_ASSERT_OWNINGTHREAD(Promise); - - // The DTOR of this WorkerHolder will release the worker for us. - mWorkerHolder = nullptr; -} - -bool -PromiseReportRejectWorkerHolder::Notify(Status aStatus) -{ - MOZ_ASSERT(aStatus > Running); - mPromise->MaybeReportRejectedOnce(); - // After this point, `this` has been deleted by RemoveWorkerHolder! - return true; -} -#endif // defined(DOM_PROMISE_DEPRECATED_REPORTING) - -bool -Promise::CaptureStack(JSContext* aCx, JS::Heap<JSObject*>& aTarget) -{ - NS_ASSERT_OWNINGTHREAD(Promise); - - JS::Rooted<JSObject*> stack(aCx); - if (!JS::CaptureCurrentStack(aCx, &stack)) { - return false; - } - aTarget = stack; - return true; -} - -void -Promise::GetDependentPromises(nsTArray<RefPtr<Promise>>& aPromises) -{ - NS_ASSERT_OWNINGTHREAD(Promise); - - // We want to return promises that correspond to then() calls, Promise.all() - // calls, and Promise.race() calls. - // - // For the then() case, we have both resolve and reject callbacks that know - // what the next promise is. - // - // For the race() case, likewise. - // - // For the all() case, our reject callback knows what the next promise is, but - // our resolve callback just knows it needs to notify some - // PromiseNativeHandler, which itself only has an indirect relationship to the - // next promise. - // - // So we walk over our _reject_ callbacks and ask each of them what promise - // its dependent promise is. - for (size_t i = 0; i < mRejectCallbacks.Length(); ++i) { - Promise* p = mRejectCallbacks[i]->GetDependentPromise(); - if (p) { - aPromises.AppendElement(p); - } - } -} - -#endif // SPIDERMONKEY_PROMISE - // A WorkerRunnable to resolve/reject the Promise on the worker thread. // Calling thread MUST hold PromiseWorkerProxy's mutex before creating this. class PromiseWorkerProxyRunnable : public WorkerRunnable @@ -3223,23 +931,6 @@ void Promise::MaybeRejectBrokenly(const nsAString& aArg) { MaybeSomething(aArg, &Promise::MaybeReject); } -#ifndef SPIDERMONKEY_PROMISE -uint64_t -Promise::GetID() { - if (mID != 0) { - return mID; - } - return mID = ++gIDGenerator; -} -#endif // SPIDERMONKEY_PROMISE - -#ifndef SPIDERMONKEY_PROMISE -Promise::PromiseState -Promise::State() const -{ - return mState; -} -#else // SPIDERMONKEY_PROMISE Promise::PromiseState Promise::State() const { @@ -3256,7 +947,6 @@ Promise::State() const return PromiseState::Pending; } -#endif // SPIDERMONKEY_PROMISE } // namespace dom } // namespace mozilla |