Bug 163437 – test262: @isConstructor incorrectly thinks Math.cos is a constructor

• Component: JavaScriptCore
• Status: RESOLVED FIXED

[Joseph Pecoraro]

test262: @isConstructor incorrectly thinks Math.cos is a constructor
test262/test/built-ins/Array/of/return-a-new-array-object.js

@isConstructor just checks that the ConstructData is not None. However, host functions return ConstructType::Host even if their default behavior is to throw an exception that it should not be used as a constructor. We could return ConstructType::None for these default cases.

[Joseph Pecoraro]

Created attachment 291596 [details]
[PATCH] Proposed Fix

[Joseph Pecoraro]

Created attachment 291599 [details]
[PATCH] Proposed Fix

Some additional test cases.

[Saam Barati]

Comment on attachment 291599 [details]
[PATCH] Proposed Fix

View in context: https://bugs.webkit.org/attachment.cgi?id=291599&action=review

r=me

> JSTests/stress/is-constructor.js:6
> +let isConstructor = createBuiltin("(function(c) { return @isConstructor(c); })");

This is a nice test.

[Saam Barati]

Comment on attachment 291599 [details]
[PATCH] Proposed Fix

View in context: https://bugs.webkit.org/attachment.cgi?id=291599&action=review

r=me

>> JSTests/stress/is-constructor.js:6
>> +let isConstructor = createBuiltin("(function(c) { return @isConstructor(c); })");
> 
> This is a nice test.

This is a nice test.

> Source/JavaScriptCore/runtime/JSFunction.cpp:576
> +        if (thisObject->nativeConstructor() == callHostFunctionAsConstructor)

Do we get a new kind of error message when we try to "new" non constructor host functions?

[Joseph Pecoraro]

Comment on attachment 291599 [details]
[PATCH] Proposed Fix

View in context: https://bugs.webkit.org/attachment.cgi?id=291599&action=review

>> Source/JavaScriptCore/runtime/JSFunction.cpp:576
>> +        if (thisObject->nativeConstructor() == callHostFunctionAsConstructor)
> 
> Do we get a new kind of error message when we try to "new" non constructor host functions?

Nope, `new Math.cos` produces the exact same error message!

[WebKit Commit Bot]

Comment on attachment 291599 [details]
[PATCH] Proposed Fix

Clearing flags on attachment: 291599

Committed r207347: <http://trac.webkit.org/changeset/207347>

[WebKit Commit Bot]

All reviewed patches have been landed.  Closing bug.