feat: add mock function to overrides non-configurable props

[buschtoens]

Based on #100. Fixes #99.

I don't know, if mock is the best name. Maybe override? I don't know. 🤷‍♀️ 😄

[VincentMolinie]

Can someone review this 🙏 ?

[boydkr]

I could very much use this PR. I'm stuck on 0.6.0 until there's some way to mock onbeforeunload

[AndreJoaquim]

Hey @simonihmig! I know you probably have more important things to do 😅 But is there any chance we could get this PR merged? It'd be very helpful 🙏🏻 Thanks in advance for all your work!

[simonihmig]

Hey folks, so the thing here is that this is based (contains those commits) on #100, which had some longer discussions a (even longer) while ago, and which seems to not have been finalized.

I am really not aware anymore of the exact state of those PRs, would need some time to dig into it again. AFAIR the work in #100 is technically required before we can land this, right?

@buschtoens what about you, are you still interested in working on these? Somehow the momentum was interrupted at some point unfortunately, and the PRs became dormant. Not intending to blame anyone here, not having the time to continue work would be totally understandable, just want to figure out if/how we can move this forward!

[simonihmig]

I'm stuck on 0.6.0 until there's some way to mock onbeforeunload

Sorry @boydkr for the late reply. Could you explain why you need this PR to mock onbeforeunload. It is a writeable prop after all, right? So that should work, unless I am missing something. In case there is an issue, but it is unrelated to this PR here - which is about overriding non-configurable, non-writable properties AFAIU - then please file a separate issue!