uv cache prune doesn't remove packages from cache for deleted environments

[neckbosov]

Steps to reproduce:

mkdir $HOME/uv-test && cd $HOME/uv-test
export UV_CACHE_DIR=$HOME/uv-test/uv-cache
uv venv --python 3.9 ./python39env
VIRTUAL_ENV=./python39env uv pip install torch
du -hs ./uv-cache

uv venv --python 3.11 ./python311env
VIRTUAL_ENV=./python311env uv pip install torch
du -hs ./uv-cache

rm -rf ./python39env
uv cache prune
du -hs ./uv-cache

Expected result:
After pruning cache size will be the same as after the first installation.

Actual result:
uv cache prune doesn't delete anything, cache size stays the same as after the second installation.

uv version 0.5.10, fedora linux.

[charliermarsh]

What do you expect to be removed after uv cache prune?

[sh-shahrokhi]

What do you expect to be removed after uv cache prune?

I have the same question. I thought torch and its dependencies should be removed.

[neckbosov]

I would expect all packages installed for python 3.9 to be removed because they are no longer used in any of environments.

[charliermarsh]

Ah, that's not the purpose of uv cache prune. We can't track "which packages are used in which environments". uv cache prune is intended to remove items that are internally unreachable from the cache (e.g., if we built a newer version of a source distribution, we can remove the older versions).