[BUG] New version 68.2.1 breaks `python setup.py --version` when using pyproject.toml

[bitbier]

setuptools version

setuptools==68.2.1

Python version

Python 3.9.13

OS

Mac OS X

Additional environment information

No response

Description

When using pyproject.toml's [project] descriptors's version attribute, the newest version of setup tools breaks with the following exception:

$ python setup.py --version
Traceback (most recent call last):
  File "/workspace/setup.py", line 2, in <module>
    setup(
  File "/Users/jstarker/.pyenv/versions/setup-version-failed/lib/python3.9/site-packages/setuptools/__init__.py", line 103, in setup
    return distutils.core.setup(**attrs)
  File "/Users/jstarker/.pyenv/versions/setup-version-failed/lib/python3.9/site-packages/setuptools/_distutils/core.py", line 172, in setup
    ok = dist.parse_command_line()
  File "/Users/jstarker/.pyenv/versions/setup-version-failed/lib/python3.9/site-packages/setuptools/_distutils/dist.py", line 467, in parse_command_line
    args = parser.getopt(args=self.script_args, object=self)
  File "/Users/jstarker/.pyenv/versions/setup-version-failed/lib/python3.9/site-packages/setuptools/_distutils/fancy_getopt.py", line 274, in getopt
    val = getattr(object, attr, 0) + 1
TypeError: can only concatenate str (not "int") to str

This works with 68.2.0.

Expected behavior

Expected to display the version of the test project

How to Reproduce

1. Create two files:

# setup.py
from setuptools import setup
setup()

# pyproject.toml
[project]
name = "test"
version = "1.0.0"

2. Install setuptools==68.2.1
3. Run python setup.py --version

Output

$ python setup.py --version
Traceback (most recent call last):
  File "/workspace/setup.py", line 2, in <module>
    setup(
  File "/Users/jstarker/.pyenv/versions/setup-version-failed/lib/python3.9/site-packages/setuptools/__init__.py", line 103, in setup
    return distutils.core.setup(**attrs)
  File "/Users/jstarker/.pyenv/versions/setup-version-failed/lib/python3.9/site-packages/setuptools/_distutils/core.py", line 172, in setup
    ok = dist.parse_command_line()
  File "/Users/jstarker/.pyenv/versions/setup-version-failed/lib/python3.9/site-packages/setuptools/_distutils/dist.py", line 467, in parse_command_line
    args = parser.getopt(args=self.script_args, object=self)
  File "/Users/jstarker/.pyenv/versions/setup-version-failed/lib/python3.9/site-packages/setuptools/_distutils/fancy_getopt.py", line 274, in getopt
    val = getattr(object, attr, 0) + 1
TypeError: can only concatenate str (not "int") to str

[abravalheri]

Hi @bitbier thank you for the feedback.

Could you please check if #4048 solves your problem?
You can install the version of setuptools with the PR with:

pip install https://github.com/abravalheri/setuptools/archive/refs/heads/issue-4047.zip

---

Remark: Please note that running setup.py as a CLI tool is deprecated. (setup.py is a perfectly valid configuration file, but the setuptools project does not want to maintain in the long term CLI capabilities). See https://blog.ganssle.io/articles/2021/10/setup-py-deprecated.html for reference. So there is no guarantee that python setup.py --version will keep working indefinitely.

[bitbier]

Hey @abravalheri,

Thanks for the quick response. I can confirm that the version above fixes the issue.

Also thanks for the information regarding the setup.py being deprecated. We are only using it as part of some custom built CI/CD tool. I'll bring this information back to our team to see if we can start looking into other things that would be more purpose built for us instead. Do you know when setup.py would be deprecated or is this just some time in the distance future?

[abravalheri]

Thank you very much @bitbier for confirming, I will proceed and release a new version soon (patch-level increment).

Do you know when setup.py would be deprecated or is this just some time in the distance future?

Running python setup.py as a CLI tool is already deprecated (it actually has been deprecated for a while).

Depending on how your custom CI/CD tool is built/expected to work, you can replace it with things like "reading the pyproject.toml file yourself"¹.

Regarding when we are going to "remove" the CLI capabilities, that is undefined. What is more likely to happen is that CLI capabilities are going to stay around for a while as long as it is not costly to keep them, but with no promise of full backwards compatibility. If we receive a report that something stopped working, we might just let it as it is (depending on the trade-off between maintenance cost and "level of breakage on the ecosystem").

In this case, it was easy to fix, so I just did it. But I cannot guarantee that is always going to be the case.

Note that having a setup.py file as a configuration file is not deprecated (and there is no expectation for doing that for the foreseeable future). setup.py is a completely fine configuration file that happens to be written in Python language (e.g. conftest.py for Pytest, noxfile.py for Nox, etc...).

Footnotes

1. This is quick and easy and works if you know that all your packages define the version inside pyproject.toml. If you need something generic that always work for all packages regardless of how they are implemented https://pypa-build.readthedocs.io/en/stable/api.html#build.util.project_wheel_metadata would probably do a better job, however it is slower. ↩