add check for specific user inherited permission

[andrewandante]

Connected to silverstripe/silverstripe-framework#10819

Allows file/folder access to be restricted on a user-by-user basis, rather than having to use groups

Issue

• ONLY_THESE_USERS is poorly named and not as useful as it should be silverstripe-framework#10817

[GuySartorelli]

One thing that's a little confusing is if you have previously set a group, and then you decide to swap to setting explicit users, the selected group is still present.

This is solved for pages by hiding the field, but as I mentioned in one of these PRs that may be out of scope for this PR... the other way to solve it would be to clear the groups if the permission type is set to something else (and same for users).... can you foresee any problems if we implemented that?

[andrewandante]

can you foresee any problems if we implemented that?

Hmm. It makes "changing back" pretty tricky, which is a bit annoying. I'd prefer to go with the "hide what is irrelevant" approach - though I could also see a "Reset to defaults"-style action which pushes everything back to Inherit and clears all the relationships. I agree it looks a bit.. mediocre 😅

[andrewandante]

@GuySartorelli presumably this needs an updated silverstripe/framework: ^5.1 constraint too?

[GuySartorelli]

Ahh, yes please! I thought I checked it for that but apparently I didn't 😅

[GuySartorelli]

LGTM