jsobject.cpp

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    // Must call toString first for Date objects.
    if ((hint == PreferString) || (hint != PreferNumber && prototype() == exec->lexicalGlobalObject()->datePrototype())) {
        JSValuePtr value = callDefaultValueFunction(exec, this, exec->propertyNames().toString);
        if (value)
            return value;
        value = callDefaultValueFunction(exec, this, exec->propertyNames().valueOf);
        if (value)
            return value;
    } else {
        JSValuePtr value = callDefaultValueFunction(exec, this, exec->propertyNames().valueOf);
        if (value)
            return value;
        value = callDefaultValueFunction(exec, this, exec->propertyNames().toString);
        if (value)
            return value;
    }

    ASSERT(!exec->hadException());

    return throwError(exec, TypeError, "No default value");
}

const HashEntry* JSObject::findPropertyHashEntry(ExecState* exec, const Identifier& propertyName) const
{
    for (const ClassInfo* info = classInfo(); info; info = info->parentClass) {
        if (const HashTable* propHashTable = info->propHashTable(exec)) {
            if (const HashEntry* entry = propHashTable->entry(exec, propertyName))
                return entry;
        }
    }
    return 0;
}

void JSObject::defineGetter(ExecState* exec, const Identifier& propertyName, JSObject* getterFunction)
{
    JSValuePtr object = getDirect(propertyName);
    if (object && object.isGetterSetter()) {
        ASSERT(m_structure->hasGetterSetterProperties());
        asGetterSetter(object)->setGetter(getterFunction);
        return;
    }

    PutPropertySlot slot;
    GetterSetter* getterSetter = new (exec) GetterSetter;
    putDirect(propertyName, getterSetter, None, true, slot);

    // putDirect will change our Structure if we add a new property. For
    // getters and setters, though, we also need to change our Structure
    // if we override an existing non-getter or non-setter.
    if (slot.type() != PutPropertySlot::NewProperty) {
        if (!m_structure->isDictionary()) {
            RefPtr<Structure> structure = Structure::getterSetterTransition(m_structure);
            setStructure(structure.release());
        }
    }

    m_structure->setHasGetterSetterProperties(true);
    getterSetter->setGetter(getterFunction);
}

void JSObject::defineSetter(ExecState* exec, const Identifier& propertyName, JSObject* setterFunction)
{
    JSValuePtr object = getDirect(propertyName);
    if (object && object.isGetterSetter()) {
        ASSERT(m_structure->hasGetterSetterProperties());
        asGetterSetter(object)->setSetter(setterFunction);
        return;
    }

    PutPropertySlot slot;
    GetterSetter* getterSetter = new (exec) GetterSetter;
    putDirect(propertyName, getterSetter, None, true, slot);

    // putDirect will change our Structure if we add a new property. For
    // getters and setters, though, we also need to change our Structure
    // if we override an existing non-getter or non-setter.
    if (slot.type() != PutPropertySlot::NewProperty) {
        if (!m_structure->isDictionary()) {
            RefPtr<Structure> structure = Structure::getterSetterTransition(m_structure);
            setStructure(structure.release());
        }
    }

    m_structure->setHasGetterSetterProperties(true);
    getterSetter->setSetter(setterFunction);
}

JSValuePtr JSObject::lookupGetter(ExecState*, const Identifier& propertyName)
{
    JSObject* object = this;
    while (true) {
        if (JSValuePtr value = object->getDirect(propertyName)) {
            if (!value.isGetterSetter())
                return jsUndefined();
            JSObject* functionObject = asGetterSetter(value)->getter();
            if (!functionObject)
                return jsUndefined();
            return functionObject;
        }

        if (!object->prototype() || !object->prototype().isObject())
            return jsUndefined();
        object = asObject(object->prototype());
    }
}

JSValuePtr JSObject::lookupSetter(ExecState*, const Identifier& propertyName)
{
    JSObject* object = this;
    while (true) {
        if (JSValuePtr value = object->getDirect(propertyName)) {
            if (!value.isGetterSetter())
                return jsUndefined();
            JSObject* functionObject = asGetterSetter(value)->setter();
            if (!functionObject)
                return jsUndefined();
            return functionObject;
        }

        if (!object->prototype() || !object->prototype().isObject())
            return jsUndefined();
        object = asObject(object->prototype());
    }
}

bool JSObject::hasInstance(ExecState* exec, JSValuePtr value, JSValuePtr proto)
{
    if (!proto.isObject()) {
        throwError(exec, TypeError, "instanceof called on an object with an invalid prototype property.");
        return false;
    }

    if (!value.isObject())
        return false;

    JSObject* object = asObject(value);
    while ((object = object->prototype().getObject())) {
        if (proto == object)
            return true;
    }
    return false;
}

bool JSObject::propertyIsEnumerable(ExecState* exec, const Identifier& propertyName) const
{
    unsigned attributes;
    if (!getPropertyAttributes(exec, propertyName, attributes))
        return false;
    return !(attributes & DontEnum);
}

bool JSObject::getPropertyAttributes(ExecState* exec, const Identifier& propertyName, unsigned& attributes) const
{
    if (m_structure->get(propertyName, attributes) != WTF::notFound)
        return true;
    
    // Look in the static hashtable of properties
    const HashEntry* entry = findPropertyHashEntry(exec, propertyName);
    if (entry) {
        attributes = entry->attributes();
        return true;
    }
    
    return false;
}

void JSObject::getPropertyNames(ExecState* exec, PropertyNameArray& propertyNames)
{
    m_structure->getEnumerablePropertyNames(exec, propertyNames, this);
}

bool JSObject::toBoolean(ExecState*) const
{
    return true;
}

double JSObject::toNumber(ExecState* exec) const
{
    JSValuePtr primitive = toPrimitive(exec, PreferNumber);
    if (exec->hadException()) // should be picked up soon in Nodes.cpp
        return 0.0;
    return primitive.toNumber(exec);
}

UString JSObject::toString(ExecState* exec) const
{
    JSValuePtr primitive = toPrimitive(exec, PreferString);
    if (exec->hadException())
        return "";
    return primitive.toString(exec);
}

JSObject* JSObject::toObject(ExecState*) const
{
    return const_cast<JSObject*>(this);
}

JSObject* JSObject::toThisObject(ExecState*) const
{
    return const_cast<JSObject*>(this);
}

JSObject* JSObject::unwrappedObject()
{
    return this;
}

void JSObject::removeDirect(const Identifier& propertyName)
{
    size_t offset;
    if (m_structure->isDictionary()) {
        offset = m_structure->removePropertyWithoutTransition(propertyName);
        if (offset != WTF::notFound)
            m_propertyStorage[offset] = jsUndefined();
        return;
    }

    RefPtr<Structure> structure = Structure::removePropertyTransition(m_structure, propertyName, offset);
    if (offset != WTF::notFound)
        m_propertyStorage[offset] = jsUndefined();
    setStructure(structure.release());
}

void JSObject::putDirectFunction(ExecState* exec, InternalFunction* function, unsigned attr)
{
    putDirect(Identifier(exec, function->name(&exec->globalData())), function, attr);
}

void JSObject::putDirectFunctionWithoutTransition(ExecState* exec, InternalFunction* function, unsigned attr)
{
    putDirectWithoutTransition(Identifier(exec, function->name(&exec->globalData())), function, attr);
}

NEVER_INLINE void JSObject::fillGetterPropertySlot(PropertySlot& slot, JSValuePtr* location)
{
    if (JSObject* getterFunction = asGetterSetter(*location)->getter())
        slot.setGetterSlot(getterFunction);
    else
        slot.setUndefined();
}

Structure* JSObject::createInheritorID()
{
    m_inheritorID = JSObject::createStructure(this);
    return m_inheritorID.get();
}

void JSObject::allocatePropertyStorage(size_t oldSize, size_t newSize)
{
    allocatePropertyStorageInline(oldSize, newSize);
}

JSObject* constructEmptyObject(ExecState* exec)
{
    return new (exec) JSObject(exec->lexicalGlobalObject()->emptyObjectStructure());
}

} // namespace JSC