1178932 - Implement ES6 Reflect.construct

Status: RESOLVED FIXED

(Core :: JavaScript Engine, defect)

Comment 1

[Jason Orendorff [:jorendorff]]

Attachment: Implement Reflect.construct

Comment 2

[Jason Orendorff [:jorendorff]]

Eric, would this help you test super()?

If so, steal reviews in bug 987514 and bug 1170307 and I'll land it today.

Comment 3

[Eric Faust [:efaust]]

Hmm. I think that even though this is useful for "recreating the same circumstances", we should still test super() in its native habitat. It's definitely a good tool for reducing crashes and doing manual translation to remove boilerplate, but I would feel weird reading "super()" tests based on R.c. That being said, it would be cool to have, so I might steal the reviews anyways.

Comment 4

[Jason Orendorff [:jorendorff]]

Attachment: Implement Reflect.construct

Comment 5

[Jason Orendorff [:jorendorff]]

Attachment: Implement Reflect.construct

Comment 6

[Jeff Walden [:Waldo]]

Comment on attachment 8634534 [details] [diff] [review]
Implement Reflect.construct

Review of attachment 8634534 [details] [diff] [review]:
-----------------------------------------------------------------

Take it if you want it, to land earlier (even in post-time-readiness).

::: js/src/tests/ecma_6/Reflect/argumentsList.js
@@ +49,3 @@
>  
>  // argumentList.length can be more than func.length.
>  function testMoar(a) {

Lulz, you actually did rename it.  :-D

::: js/src/tests/ecma_6/Reflect/construct.js
@@ +22,5 @@
> +// JS functions:
> +function f(x) { this.x = x; }
> +assertDeepEq(Reflect.construct(f, [3]), new f(3));
> +f.prototype = Array.prototype;
> +assertDeepEq(Reflect.construct(f, [3]), new f(3));

Also assert inequality of the old |new f(3)| and the new |new f(3)|'s prototypes?  Or their equality to the initial f.prototype and to Array.prototype respectively.

@@ +26,5 @@
> +assertDeepEq(Reflect.construct(f, [3]), new f(3));
> +
> +// Bound functions:
> +var bound = f.bind(null, "carrot");
> +assertDeepEq(Reflect.construct(bound, []), new bound);

Also assert deep equality with new f("carrot")?

@@ +54,5 @@
> +
> +        assertDeepEq(Reflect.construct(Base, []), new Base);
> +        //assertDeepEq(Reflect.construct(Derived, [7]), new Derived(7));
> +        //g = Derived.bind(null, "q");
> +        //assertDeepEq(Reflect.construct(g, [8, 9]), new g(8, 9));

Compare against new Derived("q", 8, 9) as well?

@@ +96,5 @@
> +    assertEq(new.target, expected);
> +    expected = undefined;
> +}
> +var expected = checkNewTarget;
> +Reflect.construct(checkNewTarget, []);

assertEq(expected, undefined) as verification, as below?

Comment 7

[Jason Orendorff [:jorendorff]]

Comment on attachment 8634534 [details] [diff] [review]
Implement Reflect.construct

Thanks, Jeff!

Comment 8

[Jason Orendorff [:jorendorff]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/e673cc171604

Comment 9

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/mozilla-central/rev/e673cc171604

Comment 10

[Florian Scholz (Open Web Docs)]

Documentation

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Reflect/construct

See also bug 987514 comment 38.