Pip: script.pip() does not work with use_module=True

Created on 15 Mar 2020 · 6Comments · Source: pypa/pip

Environment

pip version: 20.1.dev0
Python version: 3.6.9
OS: Linux Mint Debian Edition

Description

While I was working on this #7810, I found that when I use script.pip("freeze") with use_module as True which is the default behaviour, it does not show any package list, while when I explicitly specify use_module as False, it does.

I found that the difference is the way the command is invoked. With use_module=True, it is invoked as python -m pip freeze and with use_module=False, it is invoked as pip freeze.

Expected behavior

Both ways, it should show up the package list.

How to Reproduce

A test can be written to verify this behaviour.

def test_pip_script(script):
    assert script.pip("freeze").stdout == script.pip("freeze", use_module=False).stdout

Output

___________________________________________________ test_pip_script ___________________________________________________
[gw4] linux -- Python 3.6.9 /home/gutsytechster/Documents/Projects/Open-Source-Projects/pip/.tox/py36/bin/python

script = <tests.lib.PipTestEnvironment object at 0x7f696adfc8d0>

    def test_pip_script(script):
>       assert script.pip("freeze").stdout == script.pip("freeze", use_module=False).stdout
E       AssertionError: assert '' == 'apipkg==1.5\natomicwrites==...zeug==0.16.0\nzipp==3.0.0\n'
E         + apipkg==1.5
E         + atomicwrites==1.3.0
E         + attrs==19.3.0
E         + cffi==1.14.0
E         + coverage==5.0.3
E         + cryptography==2.8
E         + csv23==0.1.6
E         + execnet==1.7.1
E         + freezegun==0.3.15
E         + importlib-metadata==1.5.0
E         + mock==4.0.1
E         + more-itertools==8.2.0
E         + pluggy==0.13.1
E         + pretend==1.0.9
E         + py==1.8.1
E         + pycparser==2.19
E         + pytest==3.8.2
E         + pytest-cov==2.8.1
E         + pytest-forked==1.1.3
E         + pytest-rerunfailures==6.0
E         + pytest-timeout==1.3.4
E         + pytest-xdist==1.27.0
E         + python-dateutil==2.8.1
E         + PyYAML==5.3
E         + scripttest==1.3
E         + six==1.14.0
E         + virtualenv==16.7.10
E         + Werkzeug==0.16.0
E         + zipp==3.0.0

tests bug maintenance

Source

gutsytechster

All 6 comments

Thanks for filing a new issue for this!

My initial response is here: https://github.com/pypa/pip/pull/7810#issuecomment-599191853. Please do follow up on that here. :)

pradyunsg on 15 Mar 2020

👍1

As you suggested, here https://github.com/pypa/pip/pull/7810#issuecomment-599191853, I have written the test. However, it fails with following stdout

====================================================== FAILURES =======================================================
___________________________________________________ test_pip_script ___________________________________________________
[gw3] linux -- Python 3.6.9 /home/gutsytechster/Documents/Projects/Open-Source-Projects/pip/.tox/py36/bin/python

script = <tests.lib.PipTestEnvironment object at 0x7fc79f3b5208>

    def test_pip_script(script):
        r1 = script.pip("--version")
        r2 = script.pip("--version", use_module=False)
>       assert r1.stdout == r2.stdout
E       AssertionError: assert 'pip 20.1.dev...python 3.6)\n' == 'pip 20.1.dev0...python 3.6)\n'
E         - pip 20.1.dev0 from /tmp/pytest-of-gutsytechster/pytest-0/popen-gw3/pip0/pip/src/pip (python 3.6)
E         + pip 20.1.dev0 from /home/gutsytechster/Documents/Projects/Open-Source-Projects/pip/.tox/py36/lib/python3.6/site-packages/pip (python 3.6)

gutsytechster on 15 Mar 2020

Ahhhh. That makes sense -- whoever implemented use_module did not take into account the nuances here. :)

pip in the PipTestEnvironment PATH is not the correct to-be-tested item. I'm not sure what the fix is TBH; maybe getting the full absolute path to an executable, when using use_module=False?

pradyunsg on 15 Mar 2020

Is it this line here https://github.com/pypa/pip/blob/master/tests/lib/__init__.py#L475, where the PATH for the testing environment is being set?

gutsytechster on 16 Mar 2020

Should be, yea. It might also be in the isolate fixture, so that would be worth taking a look at.

pradyunsg on 19 Mar 2020

👍1

I found out this is because we don't have pip executable file in the virtual environment's Scripts folder.
So we can execute python [...]/src/pip at https://github.com/pypa/pip/blob/c7bde5bf88c70ac3f807db7d9e7d19745bc0a2e0/tests/lib/__init__.py#L619
[...]/src/pip means the absolote path defined in https://github.com/pypa/pip/blob/c7bde5bf88c70ac3f807db7d9e7d19745bc0a2e0/tests/conftest.py#L285
I'm not sure this is correct. But this can fix the bug.
And in https://github.com/pypa/pip/blob/c7bde5bf88c70ac3f807db7d9e7d19745bc0a2e0/tests/conftest.py#L294 it removes all files in venv.bin (which is the Scripts folder) except those start with "python" or "libpy", what does non-relocatable mean?