1074571 - The delete operator should trigger TDZ

Status: RESOLVED FIXED

(Core :: JavaScript Engine, defect)

Comment 1

[Shu-yu Guo [:shu]]

Attachment: Make the delete operator trigger TDZ.

I missed this completely.

Comment 2

[Jeff Walden [:Waldo]]

Comment on attachment 8497194 [details] [diff] [review]
Make the delete operator trigger TDZ.

Review of attachment 8497194 [details] [diff] [review]:
-----------------------------------------------------------------

::: js/src/jit-test/tests/basic/letTDZDelete.js
@@ +10,5 @@
> +
> +assertThrowsReferenceError(function () { delete x; let x; });
> +
> +// FIXME bug 611388
> +//assertThrowsReferenceError(function () { delete x; const x; });

Make this something like

function constIsLexical()
{
  try {
    (function() { parseInt(z); const z; })();
    return false;
  } catch (e) {
    return true;
  }
}

// FIXME do this unconditionally when bug 611388 is fixt
if (constIsLexical())
  assertThrowsReferenceError(function () { delete x; const x; });

so that this test complains vocally and *forces* itself to be updated when const is made lexical.

Comment 3

[Shu-yu Guo [:shu]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/da1b3063095c

Comment 4

[Ekanan Ketunuti]

https://hg.mozilla.org/mozilla-central/rev/da1b3063095c

Comment 5

[Florian Scholz (Open Web Docs)]

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/delete#Temporal_dead_zone
https://developer.mozilla.org/en-US/Firefox/Releases/36#JavaScript

Doc review appreciated (as always).