prometheus/cmd/promtool/testdata/failing.yml

tests:
  # Simple failing test.
  - interval: 1m
    input_series:
      - series: test
        values: '0'

    promql_expr_test:
      - expr: test
        eval_time: 0m
        exp_samples:
          - value: 1
            labels: test

    alert_rule_test:
      - eval_time: 0m
        alertname: Test
        exp_alerts:
          - exp_labels: {}