Add the --ignore-undeclared imports option

[Nour-Mws]

This is the symmetrical change to #151. The name --ignore-undeclared-imports symmetrical to --ignore-unused-deps would be too long. Let me know if you'd prefer renaming the old one or making the current one longer to keep the symmetry.

As with #151, the change will only impact one action (--check-undeclared):

• --list-imports: imports are still parsed as before, the ignored list does not extend to parsed imports.
• --check-unused: only undeclared imports may be ignored. If a dependency is unused, including it in the ignored list will have no effect. It will still be reported as unused.
• If an import is both used and has been declared in dependencies, including it in the ignore list will not make it unused.

Note: Since there is some refactoring in the last commits, I suggest reviewing commit by commit.

[Nour-Mws]

I updated the help message of the new option, see 5420333.

[mknorps]

This looks very good. The beauty of symmetry <3
Also works like a charm. The comments in --help are very helpful, and they provide a way to add a single name and a list to the --ignore options! 🚀

One further action point discussed in different places and maybe deserving its own issue:

• It would be great that for compare_imports_to_depenencies function we had 3 arguments:
  • gathered imports
  • gathered dependencies
  • additional options
    It is related also to the configuration options in pyproject.toml.

[jherland]

One further action point discussed in different places and maybe deserving its own issue:

• It would be great that for compare_imports_to_depenencies function we had 3 arguments:

  • gathered imports
  • gathered dependencies
  • additional options
    It is related also to the configuration options in pyproject.toml.

Yes, in my ongoing settings work, that is exactly what I'm aiming for: a Settings object that collect all our configuration from command-line and pyproject.toml, and is then passed around to whoever needs it. Might even end up in the JSON...