Bug 168684 – [JSC] It should be possible create a label named let when parsing Statement in non strict mode

• Component: JavaScriptCore
• Status: RESOLVED FIXED

[Caio Lima]

i.e case like the following codes:

```
if (true) let: x()
```

or

```
with ({}) let: y()
```

[Caio Lima]

Created attachment 302324 [details]
WIP - Patch

It starts. I still need to test it and create test cases.

[Build Bot]

Comment on attachment 302324 [details]
WIP - Patch

Attachment 302324 [details] did not pass jsc-ews (mac):
Output: http://webkit-queues.webkit.org/results/3168805

New failing tests:
jsc-layout-tests.yaml/js/script-tests/let-syntax.js.layout-no-llint
ChakraCore.yaml/ChakraCore/test/LetConst/DeclOutofBlock.js.default
jsc-layout-tests.yaml/js/script-tests/let-syntax.js.layout-no-cjit
jsc-layout-tests.yaml/js/script-tests/let-syntax.js.layout-ftl-no-cjit
ChakraCore.yaml/ChakraCore/test/strict/bug212755.js.default
jsc-layout-tests.yaml/js/script-tests/let-syntax.js.layout-dfg-eager-no-cjit
jsc-layout-tests.yaml/js/script-tests/let-syntax.js.layout
jsc-layout-tests.yaml/js/script-tests/let-syntax.js.layout-no-ftl
jsc-layout-tests.yaml/js/script-tests/let-syntax.js.layout-ftl-eager-no-cjit
ChakraCore.yaml/ChakraCore/test/strict/comma_bug219390.js.default

[Build Bot]

Comment on attachment 302324 [details]
WIP - Patch

Attachment 302324 [details] did not pass mac-wk2-ews (mac-wk2):
Output: http://webkit-queues.webkit.org/results/3168979

New failing tests:
js/let-syntax.html

[Build Bot]

Created attachment 302340 [details]
Archive of layout-test-results from ews104 for mac-elcapitan-wk2

The attached test failures were seen while running run-webkit-tests on the mac-wk2-ews.
Bot: ews104  Port: mac-elcapitan-wk2  Platform: Mac OS X 10.11.6

[Build Bot]

Comment on attachment 302324 [details]
WIP - Patch

Attachment 302324 [details] did not pass mac-debug-ews (mac):
Output: http://webkit-queues.webkit.org/results/3168997

New failing tests:
js/let-syntax.html

[Build Bot]

Created attachment 302344 [details]
Archive of layout-test-results from ews117 for mac-elcapitan

The attached test failures were seen while running run-webkit-tests on the mac-debug-ews.
Bot: ews117  Port: mac-elcapitan  Platform: Mac OS X 10.11.6

[Build Bot]

Comment on attachment 302324 [details]
WIP - Patch

Attachment 302324 [details] did not pass ios-sim-ews (ios-simulator-wk2):
Output: http://webkit-queues.webkit.org/results/3169004

New failing tests:
js/let-syntax.html

[Build Bot]

Created attachment 302345 [details]
Archive of layout-test-results from ews126 for ios-simulator-wk2

The attached test failures were seen while running run-webkit-tests on the ios-sim-ews.
Bot: ews126  Port: ios-simulator-wk2  Platform: Mac OS X 10.11.6

[Build Bot]

Comment on attachment 302324 [details]
WIP - Patch

Attachment 302324 [details] did not pass mac-ews (mac):
Output: http://webkit-queues.webkit.org/results/3171878

New failing tests:
js/let-syntax.html

[Build Bot]

Created attachment 302383 [details]
Archive of layout-test-results from ews101 for mac-elcapitan

The attached test failures were seen while running run-webkit-tests on the mac-ews.
Bot: ews101  Port: mac-elcapitan  Platform: Mac OS X 10.11.6

[Caio Lima]

Created attachment 304040 [details]
Patch

[Caio Lima]

Created attachment 304118 [details]
Patch

[Saam Barati]

Comment on attachment 304118 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=304118&action=review

r=me with comments

> Source/JavaScriptCore/parser/Parser.cpp:1729
> +    case LET: {
> +        if (!strictMode()) {
> +            bool allowFunctionDeclarationAsStatement = false;
> +            result = parseExpressionOrLabelStatement(context, allowFunctionDeclarationAsStatement);
> +            shouldSetPauseLocation = !context.shouldSkipPauseLocation(result);
> +            break;
> +        }
> +        goto defaultCase;
> +    }

This is duplicate code with he IDENT/AWAIT/YIELD case below. Maybe add a goto to that case, or make a lambda that is called both here and there.

> LayoutTests/js/script-tests/let-syntax.js:56
> +function shouldNotHaveSyntaxErrorSloopyOnly(str)

Typo: "Sloopy" => "Sloppy"

> LayoutTests/js/script-tests/let-syntax.js:96
> +shouldNotHaveSyntaxErrorSloopyOnly("let x; with ({}) let: y = 3;");

Can you also add a test where you omit the ":" after the label. Something like:

"let x; with ({}) let y = 3;"

And it should be a syntax error in sloppy mode.

[Caio Lima]

(In reply to comment #13)
> Comment on attachment 304118 [details]
> Patch
> 
> View in context:
> https://bugs.webkit.org/attachment.cgi?id=304118&action=review
> 
> r=me with comments
> 
> > Source/JavaScriptCore/parser/Parser.cpp:1729
> > +    case LET: {
> > +        if (!strictMode()) {
> > +            bool allowFunctionDeclarationAsStatement = false;
> > +            result = parseExpressionOrLabelStatement(context, allowFunctionDeclarationAsStatement);
> > +            shouldSetPauseLocation = !context.shouldSkipPauseLocation(result);
> > +            break;
> > +        }
> > +        goto defaultCase;
> > +    }
> 
> This is duplicate code with he IDENT/AWAIT/YIELD case below. Maybe add a
> goto to that case, or make a lambda that is called both here and there.

Done.

> > LayoutTests/js/script-tests/let-syntax.js:56
> > +function shouldNotHaveSyntaxErrorSloopyOnly(str)
> 
> Typo: "Sloopy" => "Sloppy"

Oops. Thanks!

> > LayoutTests/js/script-tests/let-syntax.js:96
> > +shouldNotHaveSyntaxErrorSloopyOnly("let x; with ({}) let: y = 3;");
> 
> Can you also add a test where you omit the ":" after the label. Something
> like:
> 
> "let x; with ({}) let y = 3;"
> 
> And it should be a syntax error in sloppy mode.

Done.

Thank you very much for the review Saam!

[Caio Lima]

Created attachment 304217 [details]
Patch

[WebKit Commit Bot]

Comment on attachment 304217 [details]
Patch

Clearing flags on attachment: 304217

Committed r213850: <http://trac.webkit.org/changeset/213850>

[WebKit Commit Bot]

All reviewed patches have been landed.  Closing bug.

[Yusuke Suzuki]

*** Bug 148098 has been marked as a duplicate of this bug. ***