message: test(integration): print and exit on unknown spec
  Panic does not print the error by default.
diff: @@ -155,15 +155,22 @@ fn filter_specs(mut all_specs: SpecMap, spec_names_to_run: Vec<&str>) -> Vec<Spe
  for spec_name in spec_names_to_run {
  specs.push((
  spec_name,
  - all_specs
  - .remove(spec_name)
  - .unwrap_or_else(|| panic!("expect spec {}", spec_name)),
  + all_specs.remove(spec_name).unwrap_or_else(|| {
  + eprintln!("Unknown spec {}", spec_name);
  + std::process::exit(1);
  + }),
  ));
  }
  specs
  }
  }
  +fn canonicalize_path<P: AsRef<Path>>(path: P) -> PathBuf {
  + path.as_ref()
  + .canonicalize()
  + .unwrap_or_else(|_| path.as_ref().to_path_buf())
  +}
  +
  fn build_specs() -> SpecMap {
  let mut specs = SpecMap::new();
  