Example #1
0
bool
ForOfIterator::next(MutableHandleValue vp, bool* done)
{
    MOZ_ASSERT(iterator);

    if (index != NOT_ARRAY) {
        ForOfPIC::Chain* stubChain = ForOfPIC::getOrCreate(cx_);
        if (!stubChain)
            return false;

        if (stubChain->isArrayNextStillSane())
            return nextFromOptimizedArray(vp, done);

        // ArrayIterator.prototype.next changed, materialize a proper
        // ArrayIterator instance and fall through to slowpath case.
        if (!materializeArrayIterator())
            return false;
    }

    RootedValue method(cx_);
    if (!GetProperty(cx_, iterator, iterator, cx_->names().next, &method))
        return false;

    InvokeArgs args(cx_);
    if (!args.init(1))
        return false;
    args.setCallee(method);
    args.setThis(ObjectValue(*iterator));
    args[0].setUndefined();
    if (!Invoke(cx_, args))
        return false;

    RootedObject resultObj(cx_, ToObject(cx_, args.rval()));
    if (!resultObj)
        return false;
    RootedValue doneVal(cx_);
    if (!GetProperty(cx_, resultObj, resultObj, cx_->names().done, &doneVal))
        return false;
    *done = ToBoolean(doneVal);
    if (*done) {
        vp.setUndefined();
        return true;
    }
    return GetProperty(cx_, resultObj, resultObj, cx_->names().value, vp);
}
bool
ForOfIterator::next(MutableHandleValue vp, bool* done)
{
    MOZ_ASSERT(iterator);
    if (index != NOT_ARRAY) {
        ForOfPIC::Chain* stubChain = ForOfPIC::getOrCreate(cx_);
        if (!stubChain)
            return false;

        if (stubChain->isArrayNextStillSane())
            return nextFromOptimizedArray(vp, done);

        // ArrayIterator.prototype.next changed, materialize a proper
        // ArrayIterator instance and fall through to slowpath case.
        if (!materializeArrayIterator())
            return false;
    }

    RootedValue v(cx_);
    if (!GetProperty(cx_, iterator, iterator, cx_->names().next, &v))
        return false;

    if (!js::Call(cx_, v, iterator, &v))
        return false;

    if (!v.isObject())
        return ThrowCheckIsObject(cx_, CheckIsObjectKind::IteratorNext);

    RootedObject resultObj(cx_, &v.toObject());
    if (!GetProperty(cx_, resultObj, resultObj, cx_->names().done, &v))
        return false;

    *done = ToBoolean(v);
    if (*done) {
        vp.setUndefined();
        return true;
    }

    return GetProperty(cx_, resultObj, resultObj, cx_->names().value, vp);
}
Example #3
0
bool
ForOfIterator::init(HandleValue iterable, NonIterableBehavior nonIterableBehavior)
{
    JSContext* cx = cx_;
    RootedObject iterableObj(cx, ToObject(cx, iterable));
    if (!iterableObj)
        return false;

    MOZ_ASSERT(index == NOT_ARRAY);

    // Check the PIC first for a match.
    if (iterableObj->is<ArrayObject>()) {
        ForOfPIC::Chain* stubChain = ForOfPIC::getOrCreate(cx);
        if (!stubChain)
            return false;

        bool optimized;
        if (!stubChain->tryOptimizeArray(cx, iterableObj.as<ArrayObject>(), &optimized))
            return false;

        if (optimized) {
            // Got optimized stub.  Array is optimizable.
            index = 0;
            iterator = iterableObj;
            return true;
        }
    }

    MOZ_ASSERT(index == NOT_ARRAY);

    // The iterator is the result of calling obj[@@iterator]().
    InvokeArgs args(cx);
    if (!args.init(0))
        return false;
    args.setThis(ObjectValue(*iterableObj));

    RootedValue callee(cx);
    RootedId iteratorId(cx, SYMBOL_TO_JSID(cx->wellKnownSymbols().iterator));
    if (!GetProperty(cx, iterableObj, iterableObj, iteratorId, &callee))
        return false;

    // If obj[@@iterator] is undefined and we were asked to allow non-iterables,
    // bail out now without setting iterator.  This will make valueIsIterable(),
    // which our caller should check, return false.
    if (nonIterableBehavior == AllowNonIterable && callee.isUndefined())
        return true;

    // Throw if obj[@@iterator] isn't callable.
    // js::Invoke is about to check for this kind of error anyway, but it would
    // throw an inscrutable error message about |method| rather than this nice
    // one about |obj|.
    if (!callee.isObject() || !callee.toObject().isCallable()) {
        UniquePtr<char[], JS::FreePolicy> bytes = DecompileValueGenerator(cx, JSDVG_SEARCH_STACK,
                                                                          iterable, nullptr);
        if (!bytes)
            return false;
        JS_ReportErrorNumber(cx, GetErrorMessage, nullptr, JSMSG_NOT_ITERABLE, bytes.get());
        return false;
    }

    args.setCallee(callee);
    if (!Invoke(cx, args))
        return false;

    iterator = ToObject(cx, args.rval());
    if (!iterator)
        return false;

    return true;
}