Since we switched to pyproject.toml, we also require setuptools>61. And it looks like setuptools, since at least 64 does not support pip install --editable the way it used to. In particular, it does not seem to be able to handle the folder structure ocrd_x/ocrd_x/__init__.py.

To reproduce:

$ pip install 'setuptools>=64'
$ make install-dev
$ python -c 'from ocrd_utils import getLogger'                                                                                                                                    
Traceback (most recent call last):                                                                                                                                                  
  File "<string>", line 1, in <module>                                                                                                                                              
ImportError: cannot import name 'getLogger' from 'ocrd_utils' (unknown location)

The problem is in setuptools package discovery:

File system entries in the current working directory whose names coincidentally match installed packages may take precedence in Python’s import system. Users are encouraged to avoid such scenarios [2].

The workaround is to use pip install -e --config-settings editable_mode=strict which this PR implements.

The proper solution is to either

a. switch away from setuptools
b. refactor the folder structure

Considering we've moved to pyproject.toml now and breaking the git history just to get --editable working without workarounds, I tend to a..

But first, let's fix with this workaround so make install-dev works again.