Bug 146339 – Array destructuring seems to not follow the ES6 spec

• Component: JavaScriptCore
• Status: RESOLVED FIXED

[Boris Zbarsky]

Consider this testcase:

  var y = "FAIL";
  Object.defineProperty(Array.prototype, 0, { get: function() { y = "PASS"; } });
  var [,x] = [,1];
  alert(y);

per spec, this should alert "PASS".  In Safari (and in a WebKit nightly), this alerts "FAIL".

[Yusuke Suzuki]

I guess this is fixed by this commit[1].

I've tried it with r185990's JSC shell and get "PASS".

var y = "FAIL";
Object.defineProperty(Array.prototype, 0, { get: function() { y = "PASS"; } });
var [,x] = [,1];
print(y);

Could you tell me the revision number?

[1]: http://trac.webkit.org/changeset/185853

[Yusuke Suzuki]

Ah, this commit[1].

[1]: http://trac.webkit.org/changeset/185791

[Boris Zbarsky]

Looks like I was on r185625.  

I can confirm that http://trac.webkit.org/changeset/185791 looks like it should fix this, and that it's fixed in r185958.  Sorry for the spurious bug report.  :(

[Yusuke Suzuki]

(In reply to comment #3)
> Looks like I was on r185625.  
> 
> I can confirm that http://trac.webkit.org/changeset/185791 looks like it
> should fix this, and that it's fixed in r185958.  Sorry for the spurious bug
> report.  :(

No problem!! I'm looking forward to seeing your reports about the other ES6 edge case areas!!!