• 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: Ubuntu 20.04.3 LTS
• Poetry version: 1.2.0a2
• Link of a Gist with the contents of your pyproject.toml file: https://gist.github.com/provinzkraut/c7b3cad8dde639effaf3b8d9fade09da

Issue

Trying to update any package with poetry add <package>@latest results in a SolverProblemError because poetry (wronlgy) assumes that the project depends on both the current and the version it's trying to install.

  SolverProblemError

  Because poetry-test depends on both cryptography (^3.4.7) and cryptography (^35.0.0), version solving failed.

  at ~/.local/share/pypoetry/venv/lib/python3.10/site-packages/poetry/puzzle/solver.py:146 in _solve
      142│             packages = result.packages
      143│         except OverrideNeeded as e:
      144│             return self.solve_in_compatibility_mode(e.overrides, use_latest=use_latest)
      145│         except SolveFailure as e:
    → 146│             raise SolverProblemError(e)
      147│ 
      148│         # NOTE passing explicit empty array for seen to reset between invocations during update + install cycle
      149│         results = dict(
      150│             depth_first_search(

How to reproduce

• Set up a new project with the provided pyproject.toml file
• Run poetry install
• Run poetry add cryptography@latest

Workaround

• Manually add the new version in pyproject.toml and run poetry update
• Run poetry remove <package_name> && poetry add <package_name> (which is not ideal because of Poetry uninstalls all dependencies when removing any dependency via poetry remove #4632)