On some systems (tested with official Debian Buster-based Python 3.6
docker image), setting the LC_ALL environment variable to en_US.UTF-8
will trigger Python into switching its preferred encoding to ASCII.
If any python process tries to read a non-ASCII file in this scenario,
it will terminate with an error.
And this is exactly what happens to pytest when it tries to load its
configuration that ansible-test supplies because the configuration
contains an em dash.
In order to bypass this issue, we replaced the em dash with a regular
dash and things started working again.
An alternative solution would be to replace the en_US.UTF-8 locale with
something safer, but unfortunately, the en_US.UTF-8 is probably as safe
as it gets.
74a103d655