Troubleshooting pkg_resources.DistributionNotFound

Why does this simple program result in a pkg_resources.DistributionNotFound error when run and how do we fix it?

#setup.py
from setuptools import setup

setup(name='my_project',
    version='0.1.0',
    packages=['my_project'],
    entry_points={
        'console_scripts': [
            'my_project = my_project.__main__:main'
        ]
     },
)

.

##my_project/__main__.py

import sys

def main(args=None):
     print("Do Something")

if __name__ == "__main__":
    main()

Build: python setup.py install --root=target --prefix=usr
Run: .\target\usr\Scripts\my_project.exe

Result

Traceback (most recent call last):
  File "D:\code-maphew\scraps\bug-dist-not-found\target\usr\Scripts\my_project-script.py", line 6, in <module>
    from pkg_resources import load_entry_point
  File "C:\ArcGIS\Pro\bin\Python\envs\arcgispro-py3\lib\site-packages\pkg_resources\__init__.py", line 3105, in <module>
    @_call_aside
  File "C:\ArcGIS\Pro\bin\Python\envs\arcgispro-py3\lib\site-packages\pkg_resources\__init__.py", line 3089, in _call_aside
    f(*args, **kwargs)
  File "C:\ArcGIS\Pro\bin\Python\envs\arcgispro-py3\lib\site-packages\pkg_resources\__init__.py", line 3118, in _initialize_master_working_set
    working_set = WorkingSet._build_master()
  File "C:\ArcGIS\Pro\bin\Python\envs\arcgispro-py3\lib\site-packages\pkg_resources\__init__.py", line 578, in _build_master
    ws.require(__requires__)
  File "C:\ArcGIS\Pro\bin\Python\envs\arcgispro-py3\lib\site-packages\pkg_resources\__init__.py", line 895, in require
    needed = self.resolve(parse_requirements(requirements))
  File "C:\ArcGIS\Pro\bin\Python\envs\arcgispro-py3\lib\site-packages\pkg_resources\__init__.py", line 781, in resolve
    raise DistributionNotFound(req, requirers)
pkg_resources.DistributionNotFound: The 'my-project==0.1.0' distribution was not found and is required by the application

This Q is similar to https://stackoverflow.com/questions/35457144/pkg-resources-distributionnotfound-when-using-a-module-installed-from-a-bdist-rp, but not building an RPM. In that Q using --prefix solved the problem. That hasn’t worked for me. I’ve replicated the same problem on Windows 10, Linux Mint, and Debian.

Full code in a repo here: https://github.com/maphew/scraps/tree/master/bug-dist-not-found

Initially posted to Stack Overflow where it has fetched some interest but no answers as yet: https://stackoverflow.com/questions/52375693/troubleshooting-pkg-resources-distributionnotfound-error

Thanks in advance for your time.

[benoit-pierre]

I also agree with the bug reporter that there seem to be a lot of unnecessary runtime dependencies: twine, wheel, keyring, semantic_version, …

Maybe a misguided attempt at working around setup_requires limitations? In which case I suggest looking into PEP 518.

[benoit-pierre]

You need to set PYTHONPATH, not PYTHONHOME (the later is for changing the location of system files for the interpreter)!

After looking at the issue you linked, and trying locally, the problem seem to be the [bdist_wininst] block in setup.cfg: after removing the block, the install complete successfully (including the scripts), and I can run the code.