evalv3: field unexpectedly allowed with struct disjunction

[rogpeppe]

What version of CUE are you using (cue version)?

$ cue version
0b06bd543bc422ab11be058443a271a6596151ab

Does this issue reproduce with the latest stable release?

Yes, back at least as far as v0.9.2

What did you do?

env CUE_EXPERIMENT=evalv3
! exec cue vet x.cue

-- x.cue --
data: {
	notAllowed: true
} & #S

#S: string | {}

What did you expect to see?

Passing test. The empty struct inside #S should be closed, not allowing any extra fields.

What did you see instead?

> env CUE_EXPERIMENT=evalv3
> ! exec cue vet x.cue
FAIL: /tmp/x.txtar:2: unexpected command success

[mpvl]

This seems to have been fixed already.

[myitcv]

@mpvl - I've just tested against f99441a and I still see this problem. i.e. @rogpeppe's repro test fails, when it should pass.