feat: allow for editable pypi source dependencies when using path

[tdejager]

This PR adds the ability to do editable installs for pypi-packages. This requires the project to also use a pyproject.toml so that we know what build system to use.

This PR takes great inspiration on how UV does it with some changes.

1. We resolve editables for multiple platforms by using the metadata separately.
2. We only* actually build the wheel on install time.
3. There is some deviating installation logic because we can install directly from locked dependencies.

I think that when this PR lands you mostly want to use editable installs for path based dependencies that you control, instead of regular path based dependencies.

Locking

For locking we actually lock whether the dependency is editable and also save a hash to the pyproject.toml, setup.cfg, or setup.py files. If any of these change, the lock file is invalidated, this is analogous to how UV does this for determining whether to re-install but their code uses the timestamp instead.

[ruben-arts]

Nice work!! It worked for some project I have on my machine. Lets share it with the world.

Some small remarks but in general I approve!

[ruben-arts]

Suggested change

	# pep440_rs = { git = "https://github.com/wolfv/uv", branch = "expose-yanks" }
	# pep508_rs = { git = "https://github.com/wolfv/uv", branch = "expose-yanks" }
	# uv-build = { git = "https://github.com/wolfv/uv", tag = "expose-yanks" }
	# uv-cache = { git = "https://github.com/wolfv/uv", branch = "expose-yanks" }
	# uv-client = { git = "https://github.com/wolfv/uv", branch = "expose-yanks" }
	# uv-dispatch = { git = "https://github.com/wolfv/uv", branch = "expose-yanks" }
	# uv-distribution = { git = "https://github.com/wolfv/uv", branch = "expose-yanks" }
	# uv-installer = { git = "https://github.com/wolfv/uv", branch = "expose-yanks" }
	# uv-interpreter = { git = "https://github.com/wolfv/uv", branch = "expose-yanks" }
	# uv-normalize = { git = "https://github.com/wolfv/uv", branch = "expose-yanks" }
	# uv-resolver = { git = "https://github.com/wolfv/uv", branch = "expose-yanks" }
	# uv-traits = { git = "https://github.com/wolfv/uv", branch = "expose-yanks" }
	# distribution-filename = { git = "https://github.com/wolfv/uv", branch = "expose-yanks" }
	# distribution-types = { git = "https://github.com/wolfv/uv", branch = "expose-yanks" }
	# install-wheel-rs = { git = "https://github.com/wolfv/uv", branch = "expose-yanks" }
	# platform-tags = { git = "https://github.com/wolfv/uv", branch = "expose-yanks" }
	# pypi-types = { git = "https://github.com/wolfv/uv", branch = "expose-yanks" }
	# requirements-txt = { git = "https://github.com/wolfv/uv", branch = "expose-yanks" }

[tdejager]

No we need to keep this because we have to patch it very often.

[ruben-arts]

Is this still uv or should this also be pixi-uv?

[tdejager]

That PR is still open :)

[henryiii]

This doesn't seem to be doing what it's supposed to do. If I add the following to particle, for example:

[tool.pixi.project]
name = "particle"
channels = ["conda-forge"]
platforms = ["osx-64"]

[tool.pixi.dependencies]
particle  = { path = ".", editable = true}

Then it does not do an editable install, and it does not install from the local path. Instead, it pulls particle from conda-forge. If the name in tool.pixi.dependencies is not valid from conda-forge, it errors. I do get this warning:

 WARN pixi::project::manifest: BETA feature `[pypi-dependencies]` enabled!

[henryiii]

Ahh, I bet I got the wrong section name. Yep, [tool.pixi.pypi-dependencies] works. It would have been nice if editable/path was an error for conda dependencies.

[tdejager]

Indeed, let's make an issue out of that :)

[pavelzw]

doesn't this clash with postinstall-production below @tdejager?

[tdejager]

Hmm yes it will get overwriten probably. But the .pth files might incorrectly stay in the prefix. We need the #1092 to do it correctly.