pip wheel should not create wheels that it will itself deem invalid

[anntzer]

• Pip version: 9.0.1
• Python version: 3.5.2
• Operating System: Arch Linux

Description:

pip wheel can create wheels that pip install will deem invalid. This should not be the case.

What I've run:

setup.py

from setuptools import setup
setup(name="foo", version="!invalid!")

then

$ pip wheel . && pip install *.whl
Processing /tmp/foo
Building wheels for collected packages: foo
  Running setup.py bdist_wheel for foo ... done
  Stored in directory: /tmp/foo
Successfully built foo
foo-_invalid_-py3-none-any.whl is not a valid wheel filename.
Exception information:
Traceback (most recent call last):
  File "/usr/lib/python3.5/site-packages/pip/basecommand.py", line 215, in main
    status = self.run(options, args)
  File "/usr/lib/python3.5/site-packages/pip/commands/install.py", line 312, in run
    wheel_cache
  File "/usr/lib/python3.5/site-packages/pip/basecommand.py", line 276, in populate_requirement_set
    wheel_cache=wheel_cache
  File "/usr/lib/python3.5/site-packages/pip/req/req_install.py", line 221, in from_line
    wheel = Wheel(link.filename)  # can raise InvalidWheelFilename
  File "/usr/lib/python3.5/site-packages/pip/wheel.py", line 631, in __init__
    "%s is not a valid wheel filename." % filename
pip.exceptions.InvalidWheelFilename: foo-_invalid_-py3-none-any.whl is not a valid wheel filename.

pip wheel doesn't even bother to warn on the version name.

As a side note, note that "interestingly", pip install . (installation from the directory) works just fine.
As a further note, I think that internal exceptions from pip should, by default, not display a traceback.

[xavfernandez]

Indeed the https://github.com/pypa/pip/blob/b559221/pip/wheel.py#L584-L588 regex seems a little too strict compared to the https://www.python.org/dev/peps/pep-0427/ requirements.

[xavfernandez]

The real issue being that pip should actually install this valid wheel (with a invalid/non PEP-440 version number).

[anntzer]

I don't have a preference, other than consistency.