Poetry: "Pipenv mode": a virtual environment manager that does not package

[thejohnfreeman]

• [x] I have searched the issues of this repo and believe that this is not a duplicate.
• [x] I have searched the documentation and believe that my question is not covered.

I'd like to be able to use Poetry to manage a virtual environment for a project that I never intend to package or publish.

My particular use case is that I want to use Python for testing a project written for another language. I just want to use Python as a cross-platform scripting language that comes with a nice test framework (pytest). I don't want to have to give my project a name or version in pyproject.toml, but Poetry refuses to create a virtual environment or install any dependencies until they are given. Pipenv doesn't have this limitation (because it doesn't try to handle packaging, which would require a name and version), so I'm using it in the meantime. I love Poetry, and I would rather use one tool, so please consider limiting name and version checks to the methods that absolutely need them.

[jacebrowning]

The --no-interaction mode (-n) will infer the name from the directory:

$ cd <my_project>
$ poetry init -n
$ poetry add pytest
$ poetry run pytest

This has worked for all my application projects (e.g. Django) that will never be packaged.

[thejohnfreeman]

Yes, and the version is defaulted. In my use case, this is sitting in a project that has a name and version in another language's ecosystem. Choosing a name is not difficult. There are two good reasons I don't want to have to give a version, though:

• I don't want the "dummy version" in pyproject.toml to confuse newcomers into thinking that there is a Python package cohabiting with the rest of the project. The project has a version that is tracked in another file specific to the other language's ecosystem.
• I don't want me or someone else to accidentally run any commands that might try to package or publish this project to PyPI. I want Poetry to warn that packaging is not possible for this project.

And If I'm not giving a version to Poetry, I might as well not give a name either.

[mwchase]

As a general workaround for the second point, you could add a trove classifier starting with "Private ::", per https://github.com/pypa/warehouse/pull/5440