Poetry Fails to Install/Update more-itertools on macOS

When running poetry self add poetry-plugin-shell, Poetry attempts to update more-itertools (from 10.5.0 -> 10.6.0), but fails with the error:

Command '['/opt/homebrew/Cellar/poetry/2.0.1/libexec/bin/python', 
'/opt/homebrew/Cellar/poetry/2.0.1/libexec/lib/python3.13/site-packages/virtualenv/seed/wheels/embed/pip-24.3.1-py3-none-any.whl/pip', 
'uninstall', 'more-itertools', '-y']' returned non-zero exit status 1.

The error indicates that more-itertools is not installed, yet Poetry still tries to uninstall it, leading to a failure.

Expected Behavior

Poetry should correctly detect whether more-itertools is installed and handle the update properly. If it’s not installed, it should install it rather than attempting an uninstall.

Environment Details

• OS: macOS (Apple Silicon)
• Python Version: 3.13.1 (Installed via Homebrew)
• Poetry Version: 2.0.1
• Package Manager: Homebrew
• Virtualenv: Poetry-managed

Steps to Reproduce

brew install python@3.13
curl -sSL https://install.python-poetry.org | python3 -
poetry self add poetry-plugin-shell

Suggested Fix

• Poetry should check if a package is installed before attempting to uninstall it.
• Ensure Poetry respects system-installed packages and does not conflict with Homebrew-managed dependencies.

Start by running the reported macOS Apple Silicon reproduction with Python 3.13.1, Homebrew Poetry 2.0.1, and poetry self add poetry-plugin-shell. Trace the self-add update of more-itertools and compare the installed-package state with the attempted uninstall; done means the command handles both installed and absent packages without the reported failure.