output of toString() of Generator is wrong

Executing following code :
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var f = function* () {}
print(f.toString());
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Output of JavaScriptCore is :
function () {}

However, the output should be :
function* () {}

BT group
2018.08.26

[Yusuke Suzuki]

Created attachment 348511 [details]
Patch

[Saam Barati]

Comment on attachment 348511 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=348511&action=review

r=me

> Source/JavaScriptCore/runtime/FunctionPrototype.cpp:136
> +        case SourceParseMode::AsyncGeneratorWrapperMethodMode:

Shouldn't this async generator method be "async* " since that's the syntax?

[Yusuke Suzuki]

Comment on attachment 348511 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=348511&action=review

Thanks!

>> Source/JavaScriptCore/runtime/FunctionPrototype.cpp:136
>> +        case SourceParseMode::AsyncGeneratorWrapperMethodMode:
> 
> Shouldn't this async generator method be "async* " since that's the syntax?

Right now, we always emit `async function* ...` even for async generator methods, as we emit `function xxx() { }` for methods.
When https://tc39.github.io/Function-prototype-toString-revision/ is integrated into JSC, we should revisit these cases.

[Yusuke Suzuki]

Landed in https://trac.webkit.org/changeset/235514/webkit

[Radar WebKit Bug Importer]

<rdar://problem/43941925>