pint.error --no-color lint rules
! stdout .
cmp stderr stderr.txt

-- stderr.txt --
level=info msg="Loading configuration file" path=.pint.hcl
rules/0001.yml:8 Fatal: incomplete rule, no alert or record key (yaml/parse)
 8 |   - expr: sum(foo)

level=info msg="Problems found" Fatal=1
level=fatal msg="Fatal error" error="problems found"
-- rules/0001.yml --
groups:
- name: foo
  rules:
  - record: "colo:test1"
    expr: sum(foo) without(job)
    labels:
      job: foo
  - expr: sum(foo)
    labels:
      job: foo
-- .pint.hcl --
rule {
    aggregate ".+" {
        keep = [ "job" ]
    }
}
