Packages can only contain one destination per file

Using poetry 1.1.4 on windows 10 / py3.8.

I have created a repo to reproduce the bug and show the workaround here

In a nutshell: a file that is included in a package can only appear in one place in the dist package.

Use case: An old project is using top-level imports (loose python files in a folder without an init file 😱). I am migrating it to be part of a package (called it "helpers" in the example).

Until everyone migrated, I want to publish this library both as a package and as top-level imports, so I thought I'd hack this into my pyproject.toml:

packages = [
    { include = "helpers" },
    { include = "os_helper.py", from = 'helpers' }
]

When I use poetry install to create an environment, I can do both import os_helper and from helpers import os_helper however when I install the package through pip, only the package syntax sill work and the top level import is gone.

The .whl file don't have any file at the root of the archive.

The workaround is to organize the backward compatibility layer in a different folder. Maybe just a symbolic link on the folder would work? 🤷‍♂️ I took this opportunity to throw in some warnings.warn(DeprecationWarning) on the top-level stuff and using "import *" instead of having copies; maybe that's the right way to do it after all! 😅

But this is probably a bug since at the minimum, poetry install and pip install should yield the same end result.

(ref: discord)