message: improve test-cargo-miri output
diff: @@ -46,12 +46,13 @@ def test(name, cmd, stdout_ref, stderr_ref, stdin=b'', env={}):
  # All good!
  return
  # Show output
  - print("--- BEGIN stdout ---")
  + print("Test stdout or stderr did not match reference!")
  + print("--- BEGIN test stdout ---")
  print(stdout, end="")
  - print("--- END stdout ---")
  - print("--- BEGIN stderr ---")
  + print("--- END test stdout ---")
  + print("--- BEGIN test stderr ---")
  print(stderr, end="")
  - print("--- END stderr ---")
  + print("--- END test stderr ---")
  fail("exit code was {}".format(p.returncode))
  def test_no_rebuild(name, cmd, env={}):
  