test commerce.payment {
  mocks Logger = SilentLogger {
    fn log(msg: String) -> Effect[()] {
      ()
    }
  }

  test "positive amount authorises" {
    let result <- authorise.call(100)
    assert result is Ok(_)
  }

  test "zero amount is declined" {
    let result <- authorise.call(0)
    assert result is Err(_)
  }
}
