Using @latest on already existing dependency fails because of case sensitive matching of poetry

• 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: MX Linux 19 (Debian 10 derivative)
• Poetry version: 1.1.0b2
• Link of a Gist with the contents of your pyproject.toml file: https://gist.github.com/hwalinga/21d833d0a3b6ca7a8724698df4736349

Issue

By the documentation it seems that if I already have an existing dependency I can update it to the latest. However, I try to update a specific package that is installed by the name pint, but the official name is Pint.

The debug clearly shows poetry’s confusion about this:

   1: derived: Pint (^0.16)
   1: conflict: demap depends on pint (^0.15)
   1: ! not pint (^0.15) is satisfied by Pint (^0.16)
   1: ! which is caused by "demap depends on Pint (^0.16)"
   1: ! thus: version solving failed

Full debug can be found here: https://gist.github.com/hwalinga/b2bc4f2425c69cfafb836790e737d65a

Poetry should, just like pip, be case-insensitive on the dependency matching. You can install any package with pip without having the correct case and Poetry should not fail of that. (This is not just the first letter, pip install PiNt will also work for example, but capitalization of the first letter is of course something that is commonly encountered, Biopython is another example of that.)

[finswimmer]

This seems to be solved. Feel free to leave a comment if you disagree.

[hwalinga]

Whoops, I still have issues with this : (

Here is another reproducible example, not case sensitive this time:

docker run -it --rm python:3.8.6-buster /bin/bash
curl -sSL https://raw.githubusercontent.com/python-poetry/poetry/master/install-poetry.py > install-poetry.py
python install-poetry.py --pre
export PATH="/root/.local/bin:$PATH"
poetry new testing
cd testing
curl -o pyproject.toml 'https://gist.githubusercontent.com/hwalinga/f3b51fd69c4284f15ee53f17980e0d94/raw/2833e068603b89e897562b372d8455784388e03f/pyproject.toml'
poetry install
poetry add -vvv pytest@latest

And the corresponding error log:

https://gist.github.com/a3a99dad6c0eb492f4d1c2748b60f52a