bug#59317: 29.0.50; Feature idea: suppress `message' output in ert batch test output

[Michael Albinus]

Stefan Kangas <stefankangas@gmail.com> writes:

Hi Stefan,
>> Besides the other arguments already given in this thread, I'd like to
>> emphasize that messages are useful even in batch mode, for successful
>> tests. This is the only way to study ert tests in batch mode, for
>> example on our CI/CD machines hydra and emba.
>
> It would be less than useful in CI, indeed.
>
> But in interactive sessions, and when running tests manually with
> e.g. M-x compile, it helps to have less noise, to find the relevant
> failures faster.

Maybe, although the messages in interactive mode go to a special *ERT
Messages* buffer.

Btw, there are test cases which depend on proper messages. See for
example autorevert-tests.el. For those tests, messages must not be
suppressed at all.

>> If messages shall be suppressed, this must be controlled by a user
>> option. However, I'm not in favor to do it at all.
>
> Agreed.  Perhaps an environment variable could also be provided, so that
> it is easier to control from the command line?

Sure. There are already several $EMACS_TEST_* environment variables, see
test/README.

Best regards, Michael.