Python - add support for Poetry and PipEnv

[agmond]

Hi,

As more and more modern Python applications start using Poetry or PipEnv for managing their dependencies, please support those packaging tools, in addition to the existing (experimental) support in requirements.txt.

Poetry
Poetry uses a pyproject.toml file to declare on dependencies, and a lock file named poetry.lock.
The dependency specification can be found here.

Examples (taken from Poetry repo):

• pyproject.toml
• poetry.lock

PipEnv
PipEnv uses Pipfile & Pipfile.lock.

Examples (taken from PipEnv repo):

• PipFile
• Pipfile.lock

[jeremylong]

The poetry.lock is supported - however, the pyproject.toml is still not supported. This may cause a gap for users of pip>10 (see https://pip.pypa.io/en/stable/reference/build-system/pyproject-toml/).

[jeremylong]

With #5404 I think we are about as close as we can get to fulfilling this enhancement request. We still do not support pyproject.toml - however, there is insufficient version information to make an analysis meaningful. Should we just add a warning if no lock file is present but we found a pyproject.toml file?

[jeremylong]

It looks like pip may also support pyproject.toml: https://pip.pypa.io/en/stable/reference/build-system/pyproject-toml/

[jeremylong]

again - sorry how long this one took me to get to. I think we have covered this entirely with the 8.1.0 release (or at least the best we can).