Vet doesn't output data files location when erroring

[marcosnils]

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

cue version 0.3.0-beta.3 linux/amd64

Does this issue reproduce with the latest release?

Latest beta release

What did you do?

Followed the example on https://cuelang.org/docs/tutorials/tour/intro/validation/

What did you expect to see?

cue vet output in the example URL listed on the link above

What did you see instead?

# cue vet data.yaml schema_ext.cue 
languages.1.name: invalid value "dutch" (out of bound =~"^\\p{Lu}"):
    ./schema_ext.cue:3:8

As you can see it's missing the error reference in the data file.

[myitcv]

Hey there @marcosnils!

Confirmed in a616925 via:

exec cue vet schema.cue data.yaml

-- data.yaml --
languages:
  - tag: en
    name: English
  - tag: nl
    name: dutch
  - tag: no
    name: Norwegian
-- schema.cue --
#Language: {
	tag:  string
	name: =~"^\\p{Lu}" // Must start with an uppercase letter.
}
languages: [...#Language]

cc @mpvl

[myitcv]

This also acts as a reminder that all of our docs/examples etc should be generated/tested.

[cueckoo]

This issue has been migrated to cue-lang/cue#681.

For more details about CUE's migration to a new home, please see cue-lang/cue#1078.