2.2.0 will install only on Python 3.6, not on 3.7 or 3.8

[nickwilliams-eventbrite]

Due to this line in setup.cfg:

https://github.com/jaraco/zipp/blob/v2.2.0/setup.cfg#L17

The wheel published to PyPi is limited to Python 3.6 and will not install on Python 3.7 or 3.8 (name has py36 and nothing else in it: zipp-2.2.0-py36-none-any.whl):

https://files.pythonhosted.org/packages/46/42/f2dd964b2a6b1921b08d661138148c1bcd3f038462a44019416f2342b618/zipp-2.2.0-py36-none-any.whl

The [options] say python_version >= 3.6, but the binary distribution setting is 3.6-only. One of these is not correct, and I suspect it's binary distribution setting. Assuming it is, the python-tag needs to be changed to either python-tag=py36.py37.py38 or to universal=1.

[jaraco]

I was worried about this. In #37, @vfazio made the case that py36 means "python 3.6 or later".

And in my testing, that's what I see.

zipp master $ python3.8 -m pip-run --no-cache-dir zipp -- -c 'pass'
Collecting zipp
  Downloading zipp-2.2.0-py36-none-any.whl (4.6 kB)
Installing collected packages: zipp
Successfully installed zipp-2.2.0

Can you describe where and how this package installs on Python 3.6 only?

[vfazio]

Is this a theoretical problem or an actual problem?

[vfazio]

root@ce09ab0be78c:/# mktemp -d
/tmp/tmp.NOhEkFwhkQ
root@ce09ab0be78c:/# cd /tmp/tmp.NOhEkFwhkQ/
root@ce09ab0be78c:/tmp/tmp.NOhEkFwhkQ# python3 -m venv venv
root@ce09ab0be78c:/tmp/tmp.NOhEkFwhkQ# . venv/bin/activate
(venv) root@ce09ab0be78c:/tmp/tmp.NOhEkFwhkQ# python -V
Python 3.7.5
(venv) root@ce09ab0be78c:/tmp/tmp.NOhEkFwhkQ# pip search zipp 
zipp (2.2.0)  - Backport of pathlib-compatible object wrapper for zip files
(venv) root@ce09ab0be78c:/tmp/tmp.NOhEkFwhkQ# pip install wheel
Collecting wheel
  Downloading https://files.pythonhosted.org/packages/8c/23/848298cccf8e40f5bbb59009b32848a4c38f4e7f3364297ab3c3e2e2cd14/wheel-0.34.2-py2.py3-none-any.whl
Installing collected packages: wheel
Successfully installed wheel-0.34.2
(venv) root@ce09ab0be78c:/tmp/tmp.NOhEkFwhkQ# pip install zipp
Collecting zipp
  Downloading https://files.pythonhosted.org/packages/46/42/f2dd964b2a6b1921b08d661138148c1bcd3f038462a44019416f2342b618/zipp-2.2.0-py36-none-any.whl
Installing collected packages: zipp
Successfully installed zipp-2.2.0
(venv) root@ce09ab0be78c:/tmp/tmp.NOhEkFwhkQ# 

[nickwilliams-eventbrite]

On our Python 3.7.6 system running on Ubuntu 16.04 and pip 19.3.1, we get the error "Could not find a version that satisfies the requirement zipp==2.2.0." It will let us install 2.1.0 and below, which does not have that line in setup.cfg, but not 2.2.0, in which that line was added. In our experience, when the version exists in PyPi but pip still spits out that error, it actually means that it couldn't find a matching version compatible with your Python version.

We manage dozens of libraries, both open source and internally, and we've always had to do something like python-tag=version.version.version to support installing on multiple versions, kind of like this: https://github.com/eventbrite/pysoa/blob/1d6fa4bd/setup.cfg#L2. My recommendation for this library is to change python-tag=py36 to python-tag=py36.py37.py38. That will create a wheel named zipp-2.2.1-py36.py37.py38-none-any.whl.

[vfazio]

The ubuntu distribution does some weird things with versioning... just an FYI

[nickwilliams-eventbrite]

The ubuntu distribution does some weird things with versioning... just an FYI

We're actually not using the Ubuntu distribution. We're downloading, compiling, and installing from python.org, because the Ubuntu distribution of Python 3.7 is hopelessly broken.

[vfazio]

FYI

(venv) root@ce09ab0be78c:/tmp/tmp.NOhEkFwhkQ# pip install pip==19.3.1
Collecting pip==19.3.1
  Downloading https://files.pythonhosted.org/packages/00/b6/9cfa56b4081ad13874b0c6f96af8ce16cfbc1cb06bedf8e9164ce5551ec1/pip-19.3.1-py2.py3-none-any.whl (1.4MB)
    100% |████████████████████████████████| 1.4MB 768kB/s 
Installing collected packages: pip
  Found existing installation: pip 18.1
    Uninstalling pip-18.1:
      Successfully uninstalled pip-18.1
Successfully installed pip-19.3.1
(venv) root@ce09ab0be78c:/tmp/tmp.NOhEkFwhkQ# pip uninstall zipp
Uninstalling zipp-2.2.0:
  Would remove:
    /tmp/tmp.NOhEkFwhkQ/venv/lib/python3.7/site-packages/zipp-2.2.0.dist-info/*
    /tmp/tmp.NOhEkFwhkQ/venv/lib/python3.7/site-packages/zipp.py
Proceed (y/n)? y
  Successfully uninstalled zipp-2.2.0
(venv) root@ce09ab0be78c:/tmp/tmp.NOhEkFwhkQ# pip install zipp
Collecting zipp
  Using cached https://files.pythonhosted.org/packages/46/42/f2dd964b2a6b1921b08d661138148c1bcd3f038462a44019416f2342b618/zipp-2.2.0-py36-none-any.whl
Installing collected packages: zipp
Successfully installed zipp-2.2.0
WARNING: You are using pip version 19.3.1; however, version 20.0.2 is available.
You should consider upgrading via the 'pip install --upgrade pip' command.
(venv) root@ce09ab0be78c:/tmp/tmp.NOhEkFwhkQ# cat /etc/os-release 
NAME="Ubuntu"
VERSION="19.10 (Eoan Ermine)"
ID=ubuntu
ID_LIKE=debian
PRETTY_NAME="Ubuntu 19.10"
VERSION_ID="19.10"
HOME_URL="https://www.ubuntu.com/"
SUPPORT_URL="https://help.ubuntu.com/"
BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/"
PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy"
VERSION_CODENAME=eoan
UBUNTU_CODENAME=eoan

[vfazio]

what version of setuptools is installed?

[jaraco]

My guess is that @nickwilliams-eventbrite is not installing from PyPI, but is installing from some other index or from a file system. @nickwilliams-eventbrite Do you have a way that we might be able to replicate your finding?

[nickwilliams-eventbrite]

Ah, @jaraco does make a good point. We're installing from an internal Devpi 5.3.0 server, not directly from PyPi. This Devpi server mirrors PyPi, and 2.2.0 is listed on the Devpi server simple index, and we can install 2.2.0 on Python 3.6 from the Devpi server, just not on Python 3.7.

[vfazio]

i think that's a limitation of the server software then? we host using Nexus as a mirror for upstream pypi and we haven't had trouble (yet)

[nickwilliams-eventbrite]

Perhaps this is a limitation (they may argue a "feature") of Devpi, but there's also a super simple fix that we already know will work (because it already works for us), which is to change the Python tag to python-tag=py36.py37.py38, which will create a wheel named zipp-2.2.1-py36.py37.py38-none-any.whl that we would be able to install. Another option that we know will work is to remove python-tag entirely. It doesn't appear to be needed to create a wheel, as Django publishes a wheel but does not have python-tag or universal: https://github.com/django/django/blob/master/setup.cfg

[vfazio]

the challenge i've had with the latter is that python 3.5 will fetch it but can't install it

[nickwilliams-eventbrite]

In my experience, python_requires = >=3.6 (which you already have) prevents that. We get the "Could not find a version" error for 2.1.0 on Python 3.5.

[vfazio]

easy way to test this, give me a sec