editable_wheel is broken in 68.1.0

[emontnemery]

setuptools version

setuptools==68.1.0

Python version

Python 3.11

OS

Linux

Additional environment information

No response

Description

setuptools 68.1.0 broke editable_wheels due to commit db3743a from #3995

To my understanding, the problem is that _find_nested_spec passes the wrong path to PathFinder.find_spec(rest, path=[parent_path])

Expected behavior

Pass the full path to PathFinder.find_spec.
Doing that requires a lookup to happen first though, which pretty much defeats the purpose of db3743a though as I understand it, which was to let Python handle the case insensitive lookup.

How to Reproduce

This is how PathFinder.find_spec treats its input path, note how it only cares about the tail of the name to lookup:

python3 -vv
>>> from importlib.machinery import PathFinder
>>> PathFinder.find_spec("components.persistent_notification.loader", ["/home/erik/development/home-assistant_fork/"])

Output

# trying /home/erik/development/home-assistant_fork/loader.cpython-311-x86_64-linux-gnu.so
# trying /home/erik/development/home-assistant_fork/loader.abi3.so
# trying /home/erik/development/home-assistant_fork/loader.so
# trying /home/erik/development/home-assistant_fork/loader.py
# trying /home/erik/development/home-assistant_fork/loader.pyc

[abravalheri]

Hi @emontnemery, thank you for opening the issue.

Could you please provide the full reproducer? In your example it is not clear where the home-assistant_fork comes from, or components.persistent_notification.loader...

[emontnemery]

I was trying to illustrate that the way in which _EditableFinder._find_nested_spec calls importlib.machinery.PathFinder.find_spec does not seem to be correct.

Here's a reproduction of the actual error we see:

Prerequisite:

Python 3.11 is the current interpreter, for example selected by pyenv

Step by step

mkdir tmp
cd tmp
python3 -m venv .venv
source .venv/bin/activate
pip3 install setuptools==68.1.0
git clone https://github.com/home-assistant/core
cd core
git checkout d44847bb239e180f86c0979bee443bd4c966ecdc
cd ..
pip3 install -e core
python3
# try to load a module which does not exist
>>> from homeassistant.components.persistent_notification import config
>>> config
<module 'homeassistant.components.persistent_notification.config' from '/home/erik/tmp/core/homeassistant/config.py'>

The problem is that, in this example, _EditableFinder._find_nested_spec calls PathFinder.find_spec like this:

PathFinder.find_spec("components.persistent_notification.config", ["/home/erik/tmp/core/homeassistant/"])

Which makes PathFinder.find_spec look for a config.py in /home/erik/tmp/core/homeassistant/ instead of in /home/erik/tmp/core/homeassistant/components/persistent_notification.
In other words, PathFinder.find_spec only cares about the tail of the name when a path list is passed to it.

https://docs.python.org/3/library/importlib.html#importlib.machinery.PathFinder.find_spec

[abravalheri]

Hi @emontnemery, thank you very much for the reproducer.

Could you please try if #4020 works for you?
You can install it with python -m pip install 'setuptools @ https://github.com/abravalheri/setuptools/archive/refs/heads/issue-4019.zip'

(You can also use setuptools @ https://github.com/abravalheri/setuptools/archive/refs/heads/issue-4019.zip in your pyproject.toml's [build-system] requires.

[emontnemery]

Thanks @abravalheri, that works!