• 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: Tested on macOS & Arch Linux
• Poetry version: 1.1.2
• Link of a Gist with the contents of your pyproject.toml file:

Issue

I converted my dependencies file using DepHell from Pipfile to requirements.txt to Poetry pyproject.toml. Trying to use this converted file, Poetry for some reason got stuck in an infinite loop. I tracked it down to one bad line.

The PyPI package has a name ruamel.yaml (with a dot), but my dependencies had it with a hyphen: ruamel-yaml

[tool.poetry.dependencies]
ruamel-yaml = "*"

Running poetry lock on such a file reproduces the infinite loop.

This may be partially causing #2094 ("Poetry is extremely slow when resolving the dependencies").

I cannot trigger this issue by using the Poetry command, however. If I write poetry add ruamel-yaml, it adds dependency with the correct name "ruamel.yaml" = "^0.16.12" and poetry lock works fine with that.