1215341 - Make assignment to const throw runtime TypeError regardless of strictness

Status: RESOLVED FIXED

(Core :: JavaScript Engine, defect)

Description

[Shu-yu Guo [:shu]]

Per ES6.

Comment 1

[Shu-yu Guo [:shu]]

Attachment: Make assignment to const errors runtime TypeErrors in the frontend and interpreter.

Comment 2

[Shu-yu Guo [:shu]]

Attachment: Make assignment to const errors runtime TypeErrors in the JITs.

Comment 3

[Shu-yu Guo [:shu]]

Attachment: Update tests.

Comment 4

[Jan de Mooij [:jandem]]

Comment on attachment 8674623 [details] [diff] [review]
Make assignment to const errors runtime TypeErrors in the JITs.

Review of attachment 8674623 [details] [diff] [review]:
-----------------------------------------------------------------

::: js/src/jit/MIR.h
@@ +7277,4 @@
>  {
> +    unsigned errorNumber_;
> +
> +    MThrowRuntimeLexicalError(unsigned errorNumber)

Nit: `explicit`

Comment 5

[Jan de Mooij [:jandem]]

Comment on attachment 8674624 [details] [diff] [review]
Update tests.

Review of attachment 8674624 [details] [diff] [review]:
-----------------------------------------------------------------

::: js/src/jit-test/tests/basic/constAssignError.js
@@ +8,5 @@
>  
> +assertTypeError("(function() { const x = 3; (function() x++)(); return x })()");
> +assertTypeError("(function() { const x = 3; (function() x++)(); return x++ })()");
> +assertTypeError("(function() { const x = 2; (function() x++)(); return ++x })()");
> +assertTypeError("(function() { const x = 2; (function() x++)(); return x += 1 })()");

While you're fixing this test, would you mind changing (4 times)
  (function() x++)
to
  (() => x++)

No deprecated syntax and nice to have a test for assigning to consts in arrows.

Comment 6

[Pulsebot]

https://hg.mozilla.org/integration/mozilla-inbound/rev/99fb98710182
https://hg.mozilla.org/integration/mozilla-inbound/rev/731543183177
https://hg.mozilla.org/integration/mozilla-inbound/rev/3664bbd6853b

Comment 7

[Phil Ringnalda (:philor)]

https://hg.mozilla.org/mozilla-central/rev/99fb98710182
https://hg.mozilla.org/mozilla-central/rev/731543183177
https://hg.mozilla.org/mozilla-central/rev/3664bbd6853b