Bug 163160

Summary: Object.freeze() and seal() should throw if [[PreventExtensions]]() fails.
Product: WebKit Reporter: Mark Lam <mark.lam>
Component: JavaScriptCoreAssignee: Mark Lam <mark.lam>
Status: RESOLVED FIXED    
Severity: Normal CC: fpizlo, ggaren, jfbastien, keith_miller, msaboff, saam, ysuzuki
Priority: P2    
Version: WebKit Local Build   
Hardware: Unspecified   
OS: Unspecified   
Attachments:
Description Flags
repro test case.
none
proposed patch.
mark.lam: review-
proposed patch. saam: review+

Description Mark Lam 2016-10-07 17:24:52 PDT 
See https://tc39.github.io/ecma262/#sec-object.freeze and https://tc39.github.io/ecma262/#sec-setintegritylevel.  If O.[[PreventExtensions]]() returns false, we should throw a TypeError but currently does not.
Comment 1 Mark Lam 2016-10-07 17:26:58 PDT 
Created attachment 290987 [details]
repro test case.
Comment 2 Mark Lam 2016-10-07 18:18:19 PDT 
Created attachment 290994 [details]
proposed patch.
Comment 3 Mark Lam 2016-10-07 18:19:24 PDT 
Comment on attachment 290994 [details]
proposed patch.

Bad patch.  That's what I get for making last minute changes.
Comment 4 Mark Lam 2016-10-07 18:20:11 PDT 
Created attachment 290996 [details]
proposed patch.
Comment 5 Saam Barati 2016-10-07 18:24:54 PDT 
Comment on attachment 290996 [details]
proposed patch.

View in context: https://bugs.webkit.org/attachment.cgi?id=290996&action=review

r=me

> Source/JavaScriptCore/runtime/ObjectConstructor.cpp:480
> +template<IntegrityLevel level>
> +bool setIntegrityLevel(ExecState* exec, VM& vm, JSObject* object)

Maybe it's worth including a link to the spec here.

> Source/JavaScriptCore/runtime/ObjectConstructor.cpp:496
> +        if (exec->propertyNames().isPrivateName(propertyName))

You should use vm to get the PropertyNames.
Comment 6 Mark Lam 2016-10-07 20:24:14 PDT 
Thanks for the review.  I've made the suggested changes.

Landed in r206948: <http://trac.webkit.org/r206948>.