Bug 42354 – Improve coverage of fast/dom/prototype-inheritance test

• Component: Tools / Tests
• Status: RESOLVED FIXED

[Kent Hansen]

The fast/dom/prototype-inheritance test uses a for..in statement to enumerate the properties of the window object. An issue with that approach is that non-enumerable properties, in particular the built-in ECMA properties, are not enumerated, and hence not tested.

Since we now have the ES5 function Object.getOwnPropertyNames implemented, it could be used in place of for..in; Object.getOwnPropertyNames returns both enumerable and non-enumerable properties. This will increase the test coverage, and as a bonus the test won't be sensitive to changes in the enumerable flag of existing properties (see https://bugs.webkit.org/show_bug.cgi?id=28771). Case in point, currently the Chromium expected results don't include the *Error constructors due to them being non-enumerable in V8 (like the spec says), whereas in JSC they are enumerable (which is what I'd ultimately like to fix, without reducing test coverage).

[Kent Hansen]

Created attachment 61632 [details]
Patch

Tested on Safari, Qt, Gtk and "manually" on Chromium (nightly build). I'm hoping the bot will catch missing properties, if any.

[Kent Hansen]

Created attachment 61940 [details]
Patch v2 (skip jscprint property)

Identical to first patch, except "jscprint" has been added to the set of properties to skip since it only shows up in debug builds. I forgot to test that configuration in the first iteration.

[Kent Hansen]

Tested on Chromium (Linux/Release) too now.

[Sam Weinig]

Comment on attachment 61940 [details]
Patch v2 (skip jscprint property)

r=me

[Kent Hansen]

Committed r63880: <http://trac.webkit.org/changeset/63880>