root/Source/bindings/v8/ScriptPromise.cpp

DEFINITIONS

1. then
2. cast

/*
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#include "config.h"
#include "bindings/v8/ScriptPromise.h"

#include "RuntimeEnabledFeatures.h"
#include "bindings/v8/V8Binding.h"
#include "bindings/v8/V8DOMWrapper.h"
#include "bindings/v8/custom/V8PromiseCustom.h"

#include <v8.h>

namespace WebCore {

ScriptPromise::ScriptPromise(v8::Handle<v8::Value> value, v8::Isolate* isolate)
{
    if (value.IsEmpty())
        return;

    if (!V8PromiseCustom::isPromise(value, isolate) && !value->IsPromise()) {
        m_promise = ScriptValue(v8::Handle<v8::Value>(), isolate);
        V8ThrowException::throwTypeError("the given value is not a Promise", isolate);
        return;
    }
    m_promise = ScriptValue(value, isolate);
}

ScriptPromise ScriptPromise::then(PassOwnPtr<ScriptFunction> onFulfilled, PassOwnPtr<ScriptFunction> onRejected)
{
    if (m_promise.hasNoValue())
        return ScriptPromise();

    v8::Local<v8::Object> promise = m_promise.v8Value().As<v8::Object>();
    v8::Local<v8::Function> v8OnFulfilled = adoptByGarbageCollector(onFulfilled);
    v8::Local<v8::Function> v8OnRejected = adoptByGarbageCollector(onRejected);

    if (V8PromiseCustom::isPromise(promise, isolate()))
        return ScriptPromise(V8PromiseCustom::then(promise, v8OnFulfilled, v8OnRejected, isolate()), isolate());

    ASSERT(promise->IsPromise());
    // Return this Promise if no handlers are given.
    // In fact it is not the exact bahavior of Promise.prototype.then
    // but that is not a problem in this case.
    v8::Local<v8::Promise> resultPromise = promise.As<v8::Promise>();
    // FIXME: Use Then once it is introduced.
    if (!v8OnFulfilled.IsEmpty()) {
        resultPromise = resultPromise->Chain(v8OnFulfilled);
        if (resultPromise.IsEmpty()) {
            // v8::Promise::Chain may return an empty value, for example when
            // the stack is exhausted.
            return ScriptPromise();
        }
    }
    if (!v8OnRejected.IsEmpty())
        resultPromise = resultPromise->Catch(v8OnRejected);

    return ScriptPromise(resultPromise, isolate());
}

ScriptPromise ScriptPromise::cast(const ScriptValue& value)
{
    if (value.hasNoValue())
        return ScriptPromise();
    v8::Local<v8::Value> v8Value(value.v8Value());
    v8::Isolate* isolate = value.isolate();
    if (V8PromiseCustom::isPromise(v8Value, isolate) || v8Value->IsPromise()) {
        return ScriptPromise(v8Value, isolate);
    }
    if (RuntimeEnabledFeatures::scriptPromiseOnV8PromiseEnabled()) {
        v8::Local<v8::Promise::Resolver> resolver = v8::Promise::Resolver::New(isolate);
        if (resolver.IsEmpty()) {
            // The Promise constructor may return an empty value, for example
            // when the stack is exhausted.
            return ScriptPromise();
        }
        resolver->Resolve(v8Value);
        return ScriptPromise(resolver->GetPromise(), isolate);
    }
    return ScriptPromise(V8PromiseCustom::toPromise(v8Value, isolate), isolate);
}

} // namespace WebCore