evalv3 regression where a pattern constraint definition allows non-matching field

[dsbenghe]

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

cue version v0.11.1

go version go1.23.4
-buildmode exe
-compiler gc
-trimpath true
CGO_ENABLED 0
GOARCH amd64
GOOS windows
GOAMD64 v1
cue.lang.version v0.11.1

Does this issue reproduce with the latest stable release?

yes

What did you do?

#ContainerVersion: [int]: string

containersMap: #ContainerVersion
containersMap: "someid": "sometag"

What did you expect to see?

An error to happen as string doesn't match the int

What did you see instead?

CUE_EXPERIMENT="evalv3,toposort,embed"

cue export -e containersMap

{
"someid": "sometag"
}

It errors out fine if evalv3 experiment is not enabled.

[mvdan]

Thank you for reporting; this does indeed look like a regression. Here is a simpler reproducer in testscript form:

# With the old evaluator.
env CUE_EXPERIMENT=evalv3=0
exec cue vet -c

# With the new evaluator.
env CUE_EXPERIMENT=evalv3=1
exec cue vet -c

-- input.cue --
package p

#Schema: [int]: string

data: #Schema
data: "foo": "bar"

As of 15f243b, I see:

# With the old evaluator. (0.010s)
> env CUE_EXPERIMENT=evalv3=0
> exec cue vet -c
[stderr]
data.foo: field not allowed:
    ./input.cue:3:10
    ./input.cue:5:7
    ./input.cue:6:7
[exit status 1]
FAIL: repro-evalv3.txtar:3: unexpected command failure
# With the new evaluator. (0.028s)
> env CUE_EXPERIMENT=evalv3=1
> exec cue vet -c

The old evaluator correctly fails, but the new evaluator succeeds unexpectedly.