Add a configuration file in documentation example for message

[Pierre-Sassoulas]

Current problem

Right now we do not show the configuration used for example. We could and it would:

• show readers what need to be done to activate the check if it's an extension, or a standard but optional check (soon ™️)
• permits to create simpler examples by lowering the values to something sane (i.e. max line length = 15 instead of having 120+ character in the example, max-return-values = 2 instead of 11...)
• demonstrate some options that can affect the message (!)

Desired solution

Show the configuration used in bad/good and use it as an example of configuration related to a message. There's some issue with this:

• How to identify related options?

It's not easy to determine that without reading the code, we struggle as much as user here.

• How to show the difference between the default value and the value being used in a test?

If the default value is 120 we need a way to show what it is if we change it to 15.

• How to handle duplication of the load-plugins warning

We already have a message for extensions right now.

Additional context

Initially discussed in #7142 (review)

[Pierre-Sassoulas]

We should do #7144 (comment), right after this is implemented.

[stdedos]

As a side issue, is there some explicit reason that "Correct code" appears before "Problematic code"? 😕

For the example of https://pylint.pycqa.org/en/latest/user_guide/messages/warning/while-used.html, I am expecting to see what my problem is (so as to make sure it matches my situation), not what the solution is (to a problem that hasn't been defined yet).

[Pierre-Sassoulas]

@DanielNoord I also think that having the bad code first would be more intuitive, because you come to see what the issue is about then for the solution, what do you think ?

[DanielNoord]

Fine with me!

@stdedos Is this something you would like to contribute to the project?

https://github.com/PyCQA/pylint/blob/a359796034afdc137b7c4c19f4f783451765dabc/doc/exts/pylint_messages.py#L275-L276

Switching these two lines around should do the trick 😄

[stdedos]

Well, since you are so kind to pinpoint me exactly where to make the fix ... 😄