Should `uv sync` sync the full workspace by default?

[charliermarsh]

If you have a virtual workspace, we do this. But for non-virtual workspaces, we sync the workspace root. It's a little bit of a footgun (see, e.g., https://github.com/astral-sh/ruff/pull/12622#issuecomment-2265469492).

[charliermarsh]

There are a few different cases to consider...

• uv sync from the workspace root
• uv sync -p foo from the workspace root
• uv sync from a workspace member (e.g., ./foo)

[zanieb]

Does this mean that all workspace requirements would no longer need to be explicit?

[charliermarsh]

I think it'd be something like:

• uv sync (and uv run by extension) always syncs the full workspace, regardless of whether you're in the top-level directory or a project.
• uv sync -p always syncs the specified package (and it could be the workspace root).

[bluss]

I have a minor concern that un run would uninstall some other part of the workspace that an already running (concurrent) uv run is using - that's a drawback of the current behaviour, I mean.

[charliermarsh]

In general uv run won't uninstall (unless your dependencies changed in some way) -- it just makes the changes necessary to get to a sufficient state, but could include some packages that you don't need.

[charliermarsh]

This has come up a few times so leaving it open for more discussion.

[jamesbraza]

I guess a good default behavior is to take a light touch, so maybe not syncing the full workspace by default makes sense.

Perhaps we can add a CLI/config arg to sync, something like --full-workspace, and provide decent docs on the decision

[vvuk]

I guess a good default behavior is to take a light touch, so maybe not syncing the full workspace by default makes sense.

Hmm.. I'd suggest the opposite -- that the good default behaviour is the least surprising one. If I've set up a workspace, I've explicitly declared "I'm going to be working with all of these members". It's very strange that uv sync sets up a venv, but doesn't install anything (unless my workspace root also happens to be a "real" project vs. just a workspace container) -- even though it does a full resolve and creates a lock file.

[charliermarsh]

I would argue that it would also be surprising, though, if any package could import any other package regardless of whether it was declared as a dependency, which is what would be enabled if we synced the entire workspace by default. We would lose any sort of enforcement of module boundaries.

[vvuk]

But don't you end up in that state anyway, once you've synced multiple members of the workspace? e.g. from what you said above -- uv run won't uninstall, so you'll have things you don't need available in the environment.

[charliermarsh]

uv run --exact will uninstall packages, as will uv sync, but yes uv run won't uninstall by default. That's a compromise, though, to make things work as expected with extras -- we don't want to remove extras between uv run --extra dev to uv run invocation, since that would be surprising to users.

[vvuk]

I think that makes workspaces much less useful. For example, the comfyui/plugins scenario can't be supported reasonably. Ideally, I'd want to specify extras as a global thing for the workspace. In other words, I wouldn't have the ability to run workspace member foo with extra thing and workspace member bar without extra thing. If I want that, why am I in a workspace to begin with? (Or if I really want that, uv run --isolated already exists.) Again, totally just my opinion, but to me:

• inside a workspace, there should be one global set of packages (the full resolution), with any extra sets globally applied across all members
• if I want to run a specific project with a different set of packages, then I should need to use --isolated

it shouldn't be up to uv to enforce perfect dependency declarations; that can be verified with --isolated, but otherwise it's a python ecosystem limitation that you can't really do this.

Edit: at the very least, an option to do this (sync everything) that can be set in the workspace root would be helpful. Then the actual default doesn't matter much.

[vvuk]

I completely missed the mention of "virtual workspace" vs. project in the initial post here. (There's also no mention of "virtual workspace" on https://docs.astral.sh/uv/concepts/workspaces/) If I just remove the [project] section (which was a dummy section -- I thought I needed one!) then I think I'm getting the behaviour that I want, but I'm currently fighting with pytorch still.

[charliermarsh]

The “virtual workspace” concept isn’t present in the docs because they’re considered legacy. We removed them in favor of non-packaged projects (projects without a build system), which you can find in the docs.

[vvuk]

Ah ok. Please don't remove them even if legacy until there's another way to get the full-workspace sync behaviour -- it's the only way to make this work right now. non-packaged projects trigger the "sync just the project" behaviour.

[charliermarsh]

You can now use uv sync --all-packages (same on uv run, uv export, etc.) to sync the full workspace.