[webkit-reviews] review denied: [Bug 177398] JSC should throw if proxy set returns falsish in strict mode context : [Attachment 371843] Patch

[bugzilla-daemon at webkit.org]

Yusuke Suzuki <ysuzuki at apple.com> has denied Alexey Shvayka
<shvaikalesh at gmail.com>'s request for review:
Bug 177398: JSC should throw if proxy set returns falsish in strict mode
context
https://bugs.webkit.org/show_bug.cgi?id=177398

Attachment 371843: Patch

https://bugs.webkit.org/attachment.cgi?id=371843&action=review




--- Comment #7 from Yusuke Suzuki <ysuzuki at apple.com> ---
Comment on attachment 371843
  --> https://bugs.webkit.org/attachment.cgi?id=371843
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=371843&action=review

Nice catch. Can you add a test for this?

> Source/JavaScriptCore/runtime/ProxyObject.cpp:483
> +    RETURN_IF_EXCEPTION(scope, encodedJSValue());

Use `false` instead of `encodedJSValue()`.

> Source/JavaScriptCore/runtime/ProxyObject.cpp:485
> +	   throwVMTypeError(exec, scope, makeString("Proxy object's 'set' trap
returned falsy value for property '", String(propertyName.uid()), "'"));

When throwing an error, we should also `return` here.

if (!success && slot.isStrictMode()) {
    throwVMTypeError(exec, scope, makeString("Proxy object's 'set' trap
returned falsy value for property '", String(propertyName.uid()), "'"));
    return false;
}

> Source/JavaScriptCore/runtime/ProxyObject.cpp:486
> +    RELEASE_AND_RETURN(scope, success);

Just returning success is OK because `success` part won't throw an error. So,
`return success`.