Support a --venv flag similar to pipenv

• I have searched the issues of this repo and believe that this is not a duplicate.

Issue

pipenv supports a flag --venv flag that simply prints the path to the existing venv, or returns a non-0 status code if it doesn’t exist. This allows solutions like https://github.com/w0rp/ale/issues/1656 to auto-detect (without unwanted side effects) whether pipenv should be used to run, for example, a linter.

The closest thing I’ve found in poetry so far to this effect is debug:info, which will unfortunately auto-create the virtualenv if it doesn’t exist, which would lead to false positives in scenarios like the ALE one.

I may be able to take a crack at this one personally, I don’t imagine it’ll be the hardest task in the world.

[zymergen-luke]

This can be closed now since @sdispater added a new feature in #731

poetry env info --path

will return the path to the environment.

You can call the following to activate your environment consistently:

source ${poetry env info --path}/bin/activate

[zymergen-luke]

@K900 I had some spare time this morning so I threw together a quick patch myself. Want to take a look and see if that’s roughly what you have in mind?