new [[HasProperty]] invariant for non-extensible objects

Raul-Sebastian Mihăilă raul.mihaila at
Sun Mar 5 14:16:12 UTC 2017

On Sun, Mar 5, 2017 at 2:52 PM, Oriol _ <oriol-bugzilla at> wrote:

> delete;
When you delete the property of an ordinary object, it stops being 'an
observable own property using [[GetOwnProperty]]'. So,
`Object.getOwnPropertyDescriptor(obj, "foo")` returns undefined afterwards.
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