Pipelines broken upgrading 1.2.2 to 1.3+ on Windows

• Poetry version: 1.3.1
• Python version: 3.10.8 and 3.11.1
• OS version and name: Ubuntu
• pyproject.toml:

• I am on the latest stable Poetry version, installed using a recommended method.
• I have searched the issues of this repo and believe that this is not a duplicate.
• I have consulted the FAQ and blog for any relevant entries or release notes.
• If an exception occurs when executing a command, I executed it again in debug mode (-vvv option) and have included the output below.

Issue

When upgrading the constraints to poetry==1.3.1 we get on logs:

pipx install --pip-args=--constraint=.github/workflows/constraints.txt poetry
creating virtual environment...
installing poetry...
Fatal error from pip prevented installation. Full pip output in file:
    C:\Program Files (x86)\pipx\logs\cmd_2022-12-18_15.24.01_pip_errors.log

pip seemed to fail to build package:
    html5lib<2.0,>=1.0

Some possibly relevant errors from pip install:
    ERROR: Cannot install poetry==1.3.1 because these package versions have conflicting dependencies.
    ERROR: ResolutionImpossible: for help visit https://pip.pypa.io/en/latest/topics/dependency-resolution/#dealing-with-dependency-conflicts
Error installing poetry.

Logs can be seen in these repos:

• https://github.com/staticdev/git-portfolio/pull/836
• https://github.com/staticdev/human-readable/pull/493
• https://github.com/staticdev/irpf-investidor/pull/322
• https://github.com/magmax/python-inquirer/actions/runs/3732191428/jobs/6331317578

[neersighted]

If you just want to have Dependabot bump Poetry for you, removing all other versions from the constraints.txt you use should be sufficient:

e.g.

pipx install --pip-args=--contraint=poetry-constraints.txt poetry

poetry-constraints.txt:

poetry==1.3.1

[neersighted]

We are well aware you are using pipx. However, pipx merely wraps pip, and thus uses pip’s solver.

You can see from the file that you linked that you are directly passing arguments to pip, which is wrapped by pipx:

--pip-args=--constraint=.github/workflows/constraints.txt

Injecting additional constraints is not in fact, the suggested/supported usage of pipx.

Furthermore, solving is involved here. You have not provided a fully-specified solution to pip, so it will do the following:

• Download the packages you requested according to the newest version allowed by the constraints you provide.
• Check if all their dependencies (per their constraints) are locally available, and fetch the newest version allowed if not.
• Repeat this recursively until it has every dependency.
• Check for incompatibility and attempt to fetch alternate versions if constraints conflict.

pip solves at install time, without a locking stage like Poetry. Poetry is just another package, and what is happening here is that your constraints are complex enough that pip is failing to come up with a working resolution on every platform.

There are three paths forward here:

• Use the suggested way to install with pipx, and do not inject additional constraints into Poetry’s environment.
• Simply pipx install poetry and then note the versions pip solved with, replacing the other versions in your constraints.txt.
• Bail out of using pip’s solver by providing a full resolution with the output of poetry export as a requirements/constraints file (if you provide every package, pip will just check compatibility and will not need to solve anything).

Your previous usage happened to work as the intersection of Poetry + your other constraints was solvable by pip. That is no longer true. We, the Poetry project, do not support install methods other than the ones we specify, and the only packages we provide are high-quality Python packages (no different from/special in comparison to anything else on PyPI).

If you try to do something more fancy/opinionated than a ‘standard’ install method like pip install (e.g. add --constraints to restrict the solution space pip uses), you are responsible for maintaining it.