Add virtualenv support

[estin]

On switching virtualenv/interpreter do reinitialize python stuff.

When I start vim, jedi use system python interpreter

But I used VirutalEnv vim plugin for switching per project.
I have many projects in tabs for one vim instance.

To solve this issue I wrote simple function for reimporting jedi lib and jedi_vim files in new virtualenv

Sorry for my poor English (

[Shougo]

I think it is impossible.
Because, jedi-vim uses python interface. The python interface uses only one interpreter.

[strycore]

I have this in my vimrc, I don't think you need more for virtualenv support for any plugin:

" Add the virtualenv's site-packages to vim path
if has('python')
py << EOF
import os.path
import sys
import vim
if 'VIRTUAL_ENV' in os.environ:
    project_base_dir = os.environ['VIRTUAL_ENV']
    sys.path.insert(0, project_base_dir)
    activate_this = os.path.join(project_base_dir, 'bin/activate_this.py')
    execfile(activate_this, dict(__file__=activate_this))
EOF
endif

[dbrgn]

Related to davidhalter/jedi#36.

The approach by @strycore looks pretty good to me. There are other ways to check whether the current interpreter session is a virtualenv, but that won't help here as we have to detect a virtualenv from outside.

The environment variable is not 100% reliable, but probably the best solution we can find.

@strycore It appears that the vim import is unnecessary, am I right? Or does it have some side effects?

[davidhalter]

davidhalter/jedi@580a4f4

Please try and test, I don't really use virtualenv.

[dbrgn]

@davidhalter You don't? Are you crazy? :)

I'll test this tonight, thanks.

[davidhalter]

@gwrtheyrn Crazy? Lazy would be the right word :-)

[dbrgn]

@davidhalter i'm not @gwrtheyrn anymore, so i guess i don't have to deal with this :p

(no, i'll try to test this tonight, really.)

[dbrgn]

Seems to work OK :) Thanks!

[davidhalter]

virtualenv support is now being mentioned here:
https://github.com/davidhalter/jedi#support

[cmcginty]

See #685