Fix logging demo test

[hidmic]

By relocating output_filter assignment. Running CI for Linux only as changes are cross-platform.

• Linux

[dirk-thomas]

Can you describe why setUpClass isn't sufficient? Is it not being called?

Also retriggered build passed:

[hidmic]

Can you describe why setUpClass isn't sufficient? Is it not being called?

At first it wasn't obvious to me either.

But deep down, it's because of this. That patch essentially duplicates test case classes through inheritance to prevent overlap of arguments bound to class methods for launch tests that use parameterization -- there's only one class definition and N different set of arguments to be bound. Now, because of that, when setUpClass() gets called cls becomes that subclass and later attempts to refer to any of the set attributes via the base class fail.

I'm not particularly happy with either change, but I deem this one less harmful. The true problem is that launch_testing parameterization is not correct in this regard. pytest solves this problem in completely different way, by providing "class"-scoped fixtures (see here).

[hidmic]

Or, alternatively, we can forbid launch_testing to bind setUpClass() arguments and change CLI tests accordingly. It doesn't look pretty, that's why it wasn't my first choice.

[dirk-thomas]

You might want to keep this empty line?

[hidmic]

Done in 9056e2d

[hidmic]

Merging