Core doesn't install python version specific dependencies

[DamienMatias]

• I am on the latest Poetry version.
• I have searched the issues of this repo and believe that this is not a duplicate.
• If an exception occurs when executing a command, I executed it again in debug mode (-vvv option).

• OS version and name: MacOS Catalina
• Poetry version: 1.1.4
• Link of a Gist with the contents of your pyproject.toml file: https://gist.github.com/DamienMatias/27b7f35d2b392e9f90c0f5b097e035f4#file-gistfile1-txt

Issue

Hello guys, I'm currently working on a package that is meant to be compatible with python ^3.6 and we added dataclasses as a dependency only for python 3.6 which gives us the following pyproject.toml

[tool.poetry]
name = "toto"
version = "0.1.0"
description = ""
authors = ["Damien Matias"]

[tool.poetry.dependencies]
python = "^3.6.1"
dataclasses = {version = "^0.7", python = ">=3.6.1,<3.7"}

[tool.poetry.dev-dependencies]

[build-system]
requires = ["poetry-core>=1.0.0"]
build-backend = "poetry.core.masonry.api"

The issue is if I try to install the package using pip in a python 36 venv, it won't install dataclasses even though it's specified

❯ pip install .
Looking in indexes: https://pypi.org/simple
Processing /private/tmp/toto
  Installing build dependencies ... done
  Getting requirements to build wheel ... done
    Preparing wheel metadata ... done
Building wheels for collected packages: toto
  Building wheel for toto (PEP 517) ... done
  Created wheel for toto: filename=toto-0.1.0-py3-none-any.whl size=1038 sha256=187322497ce6ccb76aa5c8b658ec322315269284b48540e69f7ed2827e60d1ea
  Stored in directory: /Users/dmatias/Library/Caches/pip/wheels/77/f6/1b/c1cd1dd9e985f0598509bf1e578353c80a4c92bcd09e765e87
Successfully built toto
Installing collected packages: toto
  Attempting uninstall: toto
    Found existing installation: toto 0.1.0
    Uninstalling toto-0.1.0:
      Successfully uninstalled toto-0.1.0
Successfully installed toto-0.1.0

Maybe this is more a https://github.com/python-poetry/poetry-core issue ?

Thank you in advance :)

[jules-ch]

Replace the comma with a space

[tool.poetry]
name = "toto"
version = "0.1.0"
description = ""
authors = ["Damien Matias"]

[tool.poetry.dependencies]
python = "^3.6.1"
dataclasses = {version = "^0.7", python = ">=3.6.1 <3.7"}



[tool.poetry.dev-dependencies]

[build-system]
requires = ["poetry-core>=1.0.0"]
build-backend = "poetry.core.masonry.api"

$ pip install .
Processing /home/jules/Code/poetry-test
  Installing build dependencies ... done
  Getting requirements to build wheel ... done
    Preparing wheel metadata ... done
Requirement already satisfied: dataclasses<0.8,>=0.7; python_version >= "3.6" and python_version < "3.7" in ./.venv/lib/python3.6/site-packages (from toto==0.1.0) (0.7)
Building wheels for collected packages: toto
  Building wheel for toto (PEP 517) ... done
  Created wheel for toto: filename=toto-0.1.0-py3-none-any.whl size=1001 sha256=376a18632f84aeaa4e29996b8d5a9f249e2fa7fef89d1d8f379c2540c81c38c9
  Stored in directory: /home/jules/.cache/pip/wheels/2c/d1/b4/cc1c7773c3ac2413562b07a53e8996e9980d5e85e9297d37a6
Successfully built toto
Installing collected packages: toto
Successfully installed toto-0.1.0

[jules-ch]

I agree documentation is not very explicit with what is considered a valid python specification for a package.

https://python-poetry.org/docs/dependency-specification/#python-restricted-dependencies

[jules-ch]

Seems to be a bug though, parse_constraint in poetry.core is working with ">=3.6.1,<3.7"

[DamienMatias]

Thank you for your answer ! I tried with your snipped and I still get the following :

❯ pip install .     
Looking in indexes: https://pypi.org/simple, https://pypi.datalab.ehda.co/simple
Processing /private/tmp/test-dataclasses
  Installing build dependencies ... done
  Getting requirements to build wheel ... done
    Preparing wheel metadata ... done
Building wheels for collected packages: toto
  Building wheel for toto (PEP 517) ... done
  Created wheel for toto: filename=toto-0.1.0-py3-none-any.whl size=1021 sha256=daa1cbccb45a9b1fa7db18ad19e3e6a3832118fde1269c32aec02c7870de17be
  Stored in directory: /Users/dmatias/Library/Caches/pip/wheels/0c/50/55/503544bf3982bd0723f09d927e804dba4b51cb2501351c5bf9
Successfully built toto
Installing collected packages: toto
  Attempting uninstall: toto
    Found existing installation: toto 0.1.0
    Uninstalling toto-0.1.0:
      Successfully uninstalled toto-0.1.0
Successfully installed toto-0.1.0

I'm using in this venv : Python 3.6.10 and Pip 20.2.4. Here is a gist of

pip install . -vvv

https://gist.github.com/DamienMatias/b1e2d1f4aba0b952ecc40678bee27e24

Do you mind sharing your python and pip version so that I can compare ?

[jules-ch]

My bad it seems to be related when specifying patch version of python in the python constraints.

[tool.poetry]
name = "toto"
version = "0.1.0"
description = ""
authors = ["Damien Matias"]

[tool.poetry.dependencies]
python = "^3.6.1"
dataclasses = {version = "^0.7", python = ">=3.6,<3.7"}



[tool.poetry.dev-dependencies]

[build-system]
requires = ["poetry-core>=1.0.0"]
build-backend = "poetry.core.masonry.api"

This one is working correctly

[DamienMatias]

It worked, thank you so much ! :D

[DamienMatias]

It works but maybe this is not a normal behavior ?

[jules-ch]

It seems to be related on how install_requires works with https://www.python.org/dev/peps/pep-0496/`. It should not include a patch version.

$ python --version
Python 3.6.12
$ python -m pip install "dataclasses ; python_version >= '3.6.1'"
Ignoring dataclasses: markers 'python_version >= "3.6.1"' don't match your environment
$ python -m pip install "dataclasses ; python_version >= '3.6'"
Collecting dataclasses
  Using cached dataclasses-0.7-py3-none-any.whl (18 kB)
Installing collected packages: dataclasses
Successfully installed dataclasses-0.7

I agree this is a weird for the user. It should be simple to add a validator for python_version to catch this before encountering this behavior.

[DamienMatias]

It makes sense, thanks again !

[sinoroc]

Maybe related: #2480