// Based on ErrorPrototype's errorProtoFuncToString(), but is modified to
// have no observable side effects to the user (i.e. does not call proxies,
// and getters).
String ErrorInstance::sanitizedToString(ExecState* exec)
{
VM& vm = exec->vm();
auto scope = DECLARE_THROW_SCOPE(vm);
JSValue nameValue;
auto namePropertName = vm.propertyNames->name;
PropertySlot nameSlot(this, PropertySlot::InternalMethodType::VMInquiry);
JSValue currentObj = this;
unsigned prototypeDepth = 0;
// We only check the current object and its prototype (2 levels) because normal
// Error objects may have a name property, and if not, its prototype should have
// a name property for the type of error e.g. "SyntaxError".
while (currentObj.isCell() && prototypeDepth++ < 2) {
JSObject* obj = jsCast<JSObject*>(currentObj);
if (JSObject::getOwnPropertySlot(obj, exec, namePropertName, nameSlot) && nameSlot.isValue()) {
nameValue = nameSlot.getValue(exec, namePropertName);
break;
}
currentObj = obj->getPrototypeDirect();
}
ASSERT(!scope.exception());
String nameString;
if (!nameValue)
nameString = ASCIILiteral("Error");
else {
nameString = nameValue.toWTFString(exec);
RETURN_IF_EXCEPTION(scope, String());
}
JSValue messageValue;
auto messagePropertName = vm.propertyNames->message;
PropertySlot messageSlot(this, PropertySlot::InternalMethodType::VMInquiry);
if (JSObject::getOwnPropertySlot(this, exec, messagePropertName, messageSlot) && messageSlot.isValue())
messageValue = messageSlot.getValue(exec, messagePropertName);
ASSERT(!scope.exception());
String messageString;
if (!messageValue)
messageString = String();
else {
messageString = messageValue.toWTFString(exec);
RETURN_IF_EXCEPTION(scope, String());
}
if (!nameString.length())
return messageString;
if (!messageString.length())
return nameString;
StringBuilder builder;
builder.append(nameString);
builder.appendLiteral(": ");
builder.append(messageString);
return builder.toString();
}
// ECMA 8.7.2
bool JSValue::putToPrimitive(ExecState* exec, PropertyName propertyName, JSValue value, PutPropertySlot& slot)
{
VM& vm = exec->vm();
auto scope = DECLARE_THROW_SCOPE(vm);
if (Optional<uint32_t> index = parseIndex(propertyName))
return putToPrimitiveByIndex(exec, index.value(), value, slot.isStrictMode());
// Check if there are any setters or getters in the prototype chain
JSObject* obj = synthesizePrototype(exec);
if (UNLIKELY(!obj))
return false;
JSValue prototype;
if (propertyName != exec->propertyNames().underscoreProto) {
for (; !obj->structure()->hasReadOnlyOrGetterSetterPropertiesExcludingProto(); obj = asObject(prototype)) {
prototype = obj->getPrototypeDirect();
if (prototype.isNull()) {
if (slot.isStrictMode())
throwTypeError(exec, scope, StrictModeReadonlyPropertyWriteError);
return false;
}
}
}
for (; ; obj = asObject(prototype)) {
unsigned attributes;
PropertyOffset offset = obj->structure()->get(vm, propertyName, attributes);
if (offset != invalidOffset) {
if (attributes & ReadOnly) {
if (slot.isStrictMode())
throwTypeError(exec, scope, StrictModeReadonlyPropertyWriteError);
return false;
}
JSValue gs = obj->getDirect(offset);
if (gs.isGetterSetter())
return callSetter(exec, *this, gs, value, slot.isStrictMode() ? StrictMode : NotStrictMode);
if (gs.isCustomGetterSetter())
return callCustomSetter(exec, gs, attributes & CustomAccessor, obj, slot.thisValue(), value);
// If there's an existing property on the object or one of its
// prototypes it should be replaced, so break here.
break;
}
prototype = obj->getPrototype(vm, exec);
if (vm.exception())
return false;
if (prototype.isNull())
break;
}
if (slot.isStrictMode())
throwTypeError(exec, scope, StrictModeReadonlyPropertyWriteError);
return false;
}
JSValueRef JSObjectGetPrototype(JSContextRef ctx, JSObjectRef object)
{
if (!ctx) {
ASSERT_NOT_REACHED();
return 0;
}
ExecState* exec = toJS(ctx);
JSLockHolder locker(exec);
JSObject* jsObject = toJS(object);
return toRef(exec, jsObject->getPrototypeDirect(exec->vm()));
}
