"files" is wrong when installed without "wheel"
When "wheel" is not installed/used, installing a package will not contain "RECORD", and it falls back to reading "SOURCES.txt" (https://gitlab.com/python-devs/importlib_metadata/blob/3150ed4da9e1267d0787c6f4c1f8258a26a1dd93/importlib_metadata/init.py#L270), which then might result in paths not being locate()
able, when a src-based setup is used:
setup(
...
packages=find_packages('src'),
package_dir={'': 'src'},
)
This is similar to #112, but in this case here it could use installed-files.txt
from the egg-info.