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

-- stderr.txt --
rules/strict.yml:2 Fatal: field alert not found in type rulefmt.RuleGroup (yaml/parse)
 2 | - alert: Conntrack_Table_Almost_Full

level=info msg="Problems found" Fatal=1
level=fatal msg="Fatal error" error="problems found"
-- rules/strict.yml --
groups:
- alert: Conntrack_Table_Almost_Full
  expr: ((node_nf_conntrack_entries / node_nf_conntrack_entries_limit) * 100) > 75
  for: 5m
  labels:
    component: conntrack
    priority: "3"
  annotations:
    summary: Conntrack table is at {{ $value|humanize }}%
