install --venv fails with existing but empty directories about devpi

[devpi-bot]

Original comment by @hpk42

Seems to work for me: https://gist.github.com/hpk42/6249348
Please re-open if i missed something and you can contribute a failing example.

[devpi-bot]

Original comment by @hellp

Ah sorry, just rewrote the issue when you wrote your comment. It fails when the directory is not a virtualenv yet. devpi states that it creates one one the fly, but fails to do so in this case.

[devpi-bot]

Original comment by @hellp

One could argue that the docs are ambiguous:

#!bash

  --venv DIR       install into specified virtualenv (created on the fly if
                   none exists).

What does it create on the fly? Just a dir or a virtualenv? At the moment it just checks for directory existence, but not if that dir is an actualy virtualenv :)

[devpi-bot]

Original comment by @hellp

#!python

    if venv:
        vpath = py.path.local(venv)
        if not vpath.check():
            hub.popen_check(["virtualenv", "-q", venv] + xopt)

I wonder if we could just remove the if vpath.check() here. Just let virtualenv's logic decide if venv is already proper or not.

Or is that dangerous? On the other hand typing "--venv bla" requires as much user intention as typing "virtualenv bla" -- with the same consequences.

[devpi-bot]

Original comment by @hpk42

Florian Schulze (@fschulze on IRC) rightfully wanted devpi to leave virtualenv's alone. I think we need to improve the detection code to check for a few more things.

[fschulze]

The upcoming devpi-client 6.0.0 will abort when the virtualenv is missing and not create one automatically anymore.