Ignore CWD for explicit package bases

[greschd]

Feature

Add an option (name TBD) to ignore the current directory when looking for namespace package bases.

As far as I can tell, the behavior would have to be modified here (optionally leaving out [os.getcwd()]:

mypy/mypy/find_sources.py

Line 87 in 695ea30

roots = mypy_path() + options.mypy_path + [os.getcwd()]

Pitch

When type-checking a repository with src/ structure, there can be conflicts between installed Python modules, and directories which are located at the root of the repository (assuming that is the CWD for running mypy).
I stumbled upon this by having a directory called docker/, while also having https://pypi.org/project/docker/ installed.

As far as I could tell, there's currently no satisfactory way for mypy to accept this, besides renaming the directory.

Happy to take a stab at implementing this, if you feel it's worth adding.

Related discussion: #8584