# Raises an error if label custom color config is using invalid regex rule
karma.bin-should-fail --log.format=text --log.config=false --log.level=error --config.file=karma.yaml
! stdout .
stderr 'msg="Failed to parse custom color regex rule ''\.\+\+\+\+'' for ''region'' label: error parsing regexp: invalid nested repetition operator: `\+\+`"'

-- karma.yaml --
alertmanager:
  servers:
    - name: default
      uri: https://localhost:9093
labels:
  color:
    custom:
      region:
        - value_re: ".++++"
          color: "#736598"
