Need your expertise on a possible bug in poetry 1.1.2 with export feature.

dependabot has just push the poetry v1.1.2 but the Tests workflow shows some failures. I’m not able currently to identify if it’s a poetry bug, an error in my implementation of hypermodern-python or link to the content of my package.

So first a link to the dependabot PR in my repo. You can then have access to the logs of the Nox test suite: https://github.com/hacf-fr/meteofrance-api/pull/41

The error is:

ERROR: In --require-hashes mode, all requirements must have their versions pinned with ==. These do not:
    typing-extensions>=3.7.4 from https://files.pythonhosted.org/packages/60/7a/e881b5abb54db0e6e671ab088d079c57ce54e8a01a3ca443f561ccadb37e/typing_extensions-3.7.4.3-py3-none-any.whl#sha256=7cb407020f00f7bfc3cb3e7881628838e69d8f3fcab2f64742a5e76b2f841918 (from black==20.8b1->-c /tmp/tmp5dcwelq_/requirements.txt (line 16))
nox > Session pre-commit failed.
Error: Process completed with exit code 1.

In my package, the pyproject.toml file contain:

typing-extensions = {version = "^3.7.4", python = "~3.6 || ~3.7"}

Because i need the class TypeDict with python 3.6 and 3.7 (not for 3.8 as this class is included in typing module). It seems that black have typing-extensions in its dependencies whatever the Python version. And due to my rule (which is exported in the requirement.txt) it raise the error above.

I’ve try to do a diff between the constraints export with poetry 1.0.10 and poetry 1.1.2 and I found that:

299c299
< typing-extensions==3.7.4.3 \
---
> typing-extensions==3.7.4.3; python_version >= "3.6" and python_version < "3.8" \
308a309,311

Do some one can help me to understand the root cause and eventually a correction or a workaround ?

[oncleben31]

Issue open: https://github.com/python-poetry/poetry/issues/3160

Thank you for the simple instructions for reproducing the bug.

[cjolowicz]

I can only assume that Poetry 1.0.10 does exactly that, compute the union of the constraints. It does look like a regression in Poetry 1.1.2, so you might open an issue for them.

Repro:

poetry new example
cd example
sed -i '/^python = /s/3.8/3.7/' pyproject.toml
poetry add --python="<3.8" typing-extensions
poetry export -f requirements.txt | grep typing
poetry add --dev black
poetry export -f requirements.txt | grep typing

Output for Poetry 1.0.10 (Python 3.8.6):

...
typing-extensions==3.7.4.3; python_version < "3.8" \
...
typing-extensions==3.7.4.3 \

Output for Poetry 1.1.2 (Python 3.8.6):

...
typing-extensions==3.7.4.3; python_version < "3.8" \
...
typing-extensions==3.7.4.3; python_version < "3.8" \