Even in new setuptools I get this error: Unknown distribution option: 'long_description_content_type'

[Flimm]

I cloned this repo, created a new virtualenv, and made sure to upgrade setuptools:

$ pip freeze --all
pip==10.0.0
setuptools==39.0.1
wheel==0.31.0

And yet when I run python setup.py, I get this warning or error:

$ python setup.py sdist
/usr/local/Cellar/python/3.6.5/Frameworks/Python.framework/Versions/3.6/lib/python3.6/distutils/dist.py:261: UserWarning: Unknown distribution option: 'long_description_content_type'
  warnings.warn(msg)
running sdist
# rest cut for brevity

Is this normal? Is the warning meant to be there? Why doesn't the new version of setuptools seem to support long_description_content_type?

[di]

You need to provide it with a command, like python setup.py sdist (to build a source distribution) or python setup.py bdist_wheel (to build a wheel distribution).

Take a look at https://packaging.python.org/tutorials/distributing-packages/#packaging-your-project for more guidance.

[Flimm]

@di Could you re-open this issue? I've edited the main issue to make it clear that even when I run python setup.py sdist, I still get the warning:

Unknown distribution option: 'long_description_content_type'

[di]

@Flimm Are you following my guide at https://dustingram.com/articles/2018/03/16/markdown-descriptions-on-pypi?

I think this error is because you are not actually using setuptools in your setup.py, you need something like:

from setuptools import setup

at the top of the file.

[Flimm]

I cloned this repo. This repo does have the line from setuptools import setup.

[di]

@Flimm What's the result of running python -c "import setuptools; print(setuptools.__version__)" for you?

[di]

@Flimm Ah, sorry. I'm remembering now that distutils will emit this warning, but everything should still work fine.

[Flimm]

Thanks. I might submit a bug report to setuptools or distutils in Python then. Just to ease my mind, could you point me to an example on Pypi.org of it working?

[di]

@Flimm It wouldn't be an appropriate bug report for setuptools since the warning is coming from distutils.

I think generally the idea with distutils is that the Python core developers are not planning to add support for any new metadata fields to it (since distutils is part of your Python distribution) so it's unlikely that you'll get a good response to your bug report.

Here's this project on PyPI: https://pypi.org/project/markdown-description-example/

[Flimm]

Could your blog post mention that this warning is expected and does not indicate a problem? https://dustingram.com/articles/2018/03/16/markdown-descriptions-on-pypi

This is a valid bug, so hopefully either Python or setuptools will be willing to do something about fixing it.

[di]

Done: di/di.github.io@b5adc2a

[impredicative]

I encountered this error. For posterity, it went away after I updated setuptools using pip, now at version 40.8.0.

[hugovk]

Already documented :)

You’ll need a version of setuptools>=38.6.0 to be able to produce a distribution with the new metadata.

https://dustingram.com/articles/2018/03/16/markdown-descriptions-on-pypi/