AttributeError : EmptyConstraint object has no attribute allows

• 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).

• Linux Pop!_OS 21.04
• Poetry 1.1.7

[tool.poetry.dependencies]
python = "^3.8"
click = "*"
python-dotenv = "*"
pandas = "*"
requests = "*"
pydantic = "*"
sqlalchemy = "*"

[tool.poetry.dev-dependencies]
pytest = "^6.2.2"

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

[tool.black]
skip-string-normalization = true

Issue

Tried both with python3.8 and python3.9 resulting in this same error.

AttributeError

  'EmptyConstraint' object has no attribute 'allows'

  at ~/anaconda3/envs/py38/lib/python3.8/site-packages/poetry/core/version/markers.py:291 in validate
      287│ 
      288│         if self._name not in environment:
      289│             return True
      290│ 
    → 291│         return self._constraint.allows(self._parser(environment[self._name]))
      292│ 
      293│     def without_extras(self):  # type: () -> MarkerTypes
      294│         return self.exclude("extra")
      295│ 

[KyleKing]

Seems to be an issue with SQLAlchemy 1.4.23 that was released ~3 hours ago. Can someone open an issue with them if not already? After work, I can submit an issue otherwise

A temporary workaround is pinning to 1.4.22 (sqlalchemy="1.4.22")

[KeksTheAllmighty]

the problem seems to be with the newest sqlalchemy in my case …