gecko-dev/dom/promise/PromiseCallback.cpp

373 строки
11 KiB
C++

/* -*- Mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; tab-width: 40 -*- */
/* vim: set ts=2 et sw=2 tw=80: */
/* 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/. */
#include "PromiseCallback.h"
#include "mozilla/dom/Promise.h"
#include "mozilla/dom/PromiseNativeHandler.h"
#include "jsapi.h"
namespace mozilla {
namespace dom {
NS_IMPL_CYCLE_COLLECTING_ADDREF(PromiseCallback)
NS_IMPL_CYCLE_COLLECTING_RELEASE(PromiseCallback)
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(PromiseCallback)
NS_INTERFACE_MAP_ENTRY(nsISupports)
NS_INTERFACE_MAP_END
NS_IMPL_CYCLE_COLLECTION_0(PromiseCallback)
PromiseCallback::PromiseCallback()
{
}
PromiseCallback::~PromiseCallback()
{
}
// ResolvePromiseCallback
NS_IMPL_CYCLE_COLLECTION_CLASS(ResolvePromiseCallback)
NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(ResolvePromiseCallback,
PromiseCallback)
NS_IMPL_CYCLE_COLLECTION_UNLINK(mPromise)
tmp->mGlobal = nullptr;
NS_IMPL_CYCLE_COLLECTION_UNLINK_END
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(ResolvePromiseCallback,
PromiseCallback)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mPromise)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_SCRIPT_OBJECTS
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN(ResolvePromiseCallback)
NS_IMPL_CYCLE_COLLECTION_TRACE_JS_MEMBER_CALLBACK(mGlobal)
NS_IMPL_CYCLE_COLLECTION_TRACE_END
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION_INHERITED(ResolvePromiseCallback)
NS_INTERFACE_MAP_END_INHERITING(PromiseCallback)
NS_IMPL_ADDREF_INHERITED(ResolvePromiseCallback, PromiseCallback)
NS_IMPL_RELEASE_INHERITED(ResolvePromiseCallback, PromiseCallback)
ResolvePromiseCallback::ResolvePromiseCallback(Promise* aPromise,
JS::Handle<JSObject*> aGlobal)
: mPromise(aPromise)
, mGlobal(aGlobal)
{
MOZ_ASSERT(aPromise);
MOZ_ASSERT(aGlobal);
HoldJSObjects(this);
}
ResolvePromiseCallback::~ResolvePromiseCallback()
{
DropJSObjects(this);
}
void
ResolvePromiseCallback::Call(JSContext* aCx,
JS::Handle<JS::Value> aValue)
{
// Run resolver's algorithm with value and the synchronous flag set.
JSAutoCompartment ac(aCx, mGlobal);
JS::Rooted<JS::Value> value(aCx, aValue);
if (!JS_WrapValue(aCx, &value)) {
NS_WARNING("Failed to wrap value into the right compartment.");
return;
}
mPromise->ResolveInternal(aCx, value);
}
// RejectPromiseCallback
NS_IMPL_CYCLE_COLLECTION_CLASS(RejectPromiseCallback)
NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(RejectPromiseCallback,
PromiseCallback)
NS_IMPL_CYCLE_COLLECTION_UNLINK(mPromise)
tmp->mGlobal = nullptr;
NS_IMPL_CYCLE_COLLECTION_UNLINK_END
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(RejectPromiseCallback,
PromiseCallback)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mPromise)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_SCRIPT_OBJECTS
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION_INHERITED(RejectPromiseCallback)
NS_INTERFACE_MAP_END_INHERITING(PromiseCallback)
NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN_INHERITED(RejectPromiseCallback,
PromiseCallback)
NS_IMPL_CYCLE_COLLECTION_TRACE_JS_MEMBER_CALLBACK(mGlobal)
NS_IMPL_CYCLE_COLLECTION_TRACE_END
NS_IMPL_ADDREF_INHERITED(RejectPromiseCallback, PromiseCallback)
NS_IMPL_RELEASE_INHERITED(RejectPromiseCallback, PromiseCallback)
RejectPromiseCallback::RejectPromiseCallback(Promise* aPromise,
JS::Handle<JSObject*> aGlobal)
: mPromise(aPromise)
, mGlobal(aGlobal)
{
MOZ_ASSERT(aPromise);
MOZ_ASSERT(mGlobal);
HoldJSObjects(this);
}
RejectPromiseCallback::~RejectPromiseCallback()
{
DropJSObjects(this);
}
void
RejectPromiseCallback::Call(JSContext* aCx,
JS::Handle<JS::Value> aValue)
{
// Run resolver's algorithm with value and the synchronous flag set.
JSAutoCompartment ac(aCx, mGlobal);
JS::Rooted<JS::Value> value(aCx, aValue);
if (!JS_WrapValue(aCx, &value)) {
NS_WARNING("Failed to wrap value into the right compartment.");
return;
}
mPromise->RejectInternal(aCx, value);
}
// WrapperPromiseCallback
NS_IMPL_CYCLE_COLLECTION_CLASS(WrapperPromiseCallback)
NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(WrapperPromiseCallback,
PromiseCallback)
NS_IMPL_CYCLE_COLLECTION_UNLINK(mNextPromise)
NS_IMPL_CYCLE_COLLECTION_UNLINK(mCallback)
tmp->mGlobal = nullptr;
NS_IMPL_CYCLE_COLLECTION_UNLINK_END
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(WrapperPromiseCallback,
PromiseCallback)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mNextPromise)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mCallback)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_SCRIPT_OBJECTS
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN(WrapperPromiseCallback)
NS_IMPL_CYCLE_COLLECTION_TRACE_JS_MEMBER_CALLBACK(mGlobal)
NS_IMPL_CYCLE_COLLECTION_TRACE_END
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION_INHERITED(WrapperPromiseCallback)
NS_INTERFACE_MAP_END_INHERITING(PromiseCallback)
NS_IMPL_ADDREF_INHERITED(WrapperPromiseCallback, PromiseCallback)
NS_IMPL_RELEASE_INHERITED(WrapperPromiseCallback, PromiseCallback)
WrapperPromiseCallback::WrapperPromiseCallback(Promise* aNextPromise,
JS::Handle<JSObject*> aGlobal,
AnyCallback* aCallback)
: mNextPromise(aNextPromise)
, mGlobal(aGlobal)
, mCallback(aCallback)
{
MOZ_ASSERT(aNextPromise);
MOZ_ASSERT(aGlobal);
HoldJSObjects(this);
}
WrapperPromiseCallback::~WrapperPromiseCallback()
{
DropJSObjects(this);
}
void
WrapperPromiseCallback::Call(JSContext* aCx,
JS::Handle<JS::Value> aValue)
{
JSAutoCompartment ac(aCx, mGlobal);
JS::Rooted<JS::Value> value(aCx, aValue);
if (!JS_WrapValue(aCx, &value)) {
NS_WARNING("Failed to wrap value into the right compartment.");
return;
}
ErrorResult rv;
// PromiseReactionTask step 6
JS::Rooted<JS::Value> retValue(aCx);
mCallback->Call(value, &retValue, rv, CallbackObject::eRethrowExceptions,
mNextPromise->Compartment());
rv.WouldReportJSException();
// PromiseReactionTask step 7
if (rv.Failed()) {
JS::Rooted<JS::Value> value(aCx);
if (rv.IsJSException()) {
rv.StealJSException(aCx, &value);
if (!JS_WrapValue(aCx, &value)) {
NS_WARNING("Failed to wrap value into the right compartment.");
return;
}
} else {
// 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(aCx, mNextPromise->GlobalJSObject());
DebugOnly<bool> conversionResult = ToJSValue(aCx, rv, &value);
MOZ_ASSERT(conversionResult);
}
mNextPromise->RejectInternal(aCx, value);
return;
}
// If the return value is the same as the promise itself, throw TypeError.
if (retValue.isObject()) {
JS::Rooted<JSObject*> valueObj(aCx, &retValue.toObject());
Promise* returnedPromise;
nsresult r = UNWRAP_OBJECT(Promise, valueObj, returnedPromise);
if (NS_SUCCEEDED(r) && returnedPromise == mNextPromise) {
const char* fileName = nullptr;
uint32_t lineNumber = 0;
// Try to get some information about the callback to report a sane error,
// but don't try too hard (only deals with scripted functions).
JS::Rooted<JSObject*> unwrapped(aCx,
js::CheckedUnwrap(mCallback->Callback()));
if (unwrapped) {
JSAutoCompartment ac(aCx, unwrapped);
if (JS_ObjectIsFunction(aCx, unwrapped)) {
JS::Rooted<JS::Value> asValue(aCx, JS::ObjectValue(*unwrapped));
JS::Rooted<JSFunction*> func(aCx, JS_ValueToFunction(aCx, asValue));
MOZ_ASSERT(func);
JSScript* script = JS_GetFunctionScript(aCx, func);
if (script) {
fileName = JS_GetScriptFilename(script);
lineNumber = JS_GetScriptBaseLineNumber(aCx, script);
}
}
}
// We're back in aValue's compartment here.
JS::Rooted<JSString*> stack(aCx, JS_GetEmptyString(JS_GetRuntime(aCx)));
JS::Rooted<JSString*> fn(aCx, JS_NewStringCopyZ(aCx, fileName));
if (!fn) {
// Out of memory. Promise will stay unresolved.
JS_ClearPendingException(aCx);
return;
}
JS::Rooted<JSString*> message(aCx,
JS_NewStringCopyZ(aCx,
"then() cannot return same Promise that it resolves."));
if (!message) {
// Out of memory. Promise will stay unresolved.
JS_ClearPendingException(aCx);
return;
}
JS::Rooted<JS::Value> typeError(aCx);
if (!JS::CreateError(aCx, JSEXN_TYPEERR, stack, fn, lineNumber, 0,
nullptr, message, &typeError)) {
// Out of memory. Promise will stay unresolved.
JS_ClearPendingException(aCx);
return;
}
mNextPromise->RejectInternal(aCx, typeError);
return;
}
}
// Otherwise, run resolver's resolve with value.
if (!JS_WrapValue(aCx, &retValue)) {
NS_WARNING("Failed to wrap value into the right compartment.");
return;
}
mNextPromise->ResolveInternal(aCx, retValue);
}
// NativePromiseCallback
NS_IMPL_CYCLE_COLLECTION_INHERITED(NativePromiseCallback,
PromiseCallback, mHandler)
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION_INHERITED(NativePromiseCallback)
NS_INTERFACE_MAP_END_INHERITING(PromiseCallback)
NS_IMPL_ADDREF_INHERITED(NativePromiseCallback, PromiseCallback)
NS_IMPL_RELEASE_INHERITED(NativePromiseCallback, PromiseCallback)
NativePromiseCallback::NativePromiseCallback(PromiseNativeHandler* aHandler,
Promise::PromiseState aState)
: mHandler(aHandler)
, mState(aState)
{
MOZ_ASSERT(aHandler);
}
NativePromiseCallback::~NativePromiseCallback()
{
}
void
NativePromiseCallback::Call(JSContext* aCx,
JS::Handle<JS::Value> aValue)
{
if (mState == Promise::Resolved) {
mHandler->ResolvedCallback(aCx, aValue);
return;
}
if (mState == Promise::Rejected) {
mHandler->RejectedCallback(aCx, aValue);
return;
}
NS_NOTREACHED("huh?");
}
/* static */ PromiseCallback*
PromiseCallback::Factory(Promise* aNextPromise, JS::Handle<JSObject*> aGlobal,
AnyCallback* aCallback, Task aTask)
{
MOZ_ASSERT(aNextPromise);
// If we have a callback and a next resolver, we have to exec the callback and
// then propagate the return value to the next resolver->resolve().
if (aCallback) {
return new WrapperPromiseCallback(aNextPromise, aGlobal, aCallback);
}
if (aTask == Resolve) {
return new ResolvePromiseCallback(aNextPromise, aGlobal);
}
if (aTask == Reject) {
return new RejectPromiseCallback(aNextPromise, aGlobal);
}
MOZ_ASSERT(false, "This should not happen");
return nullptr;
}
} // namespace dom
} // namespace mozilla