## Summary
This PR modifies the resolver to treat the Python version as a package,
which allows for better error messages (since we no longer treat
incompatible packages as if they "don't exist at all").
There are a few tricky pieces here...
First, we need to track both the interpreter's Python version and the
_target_ Python version, because we support resolving for other versions
via `--python 3.7`.
Second, we allow using incompatible wheels during resolution, as long as
there's a compatible source distribution. So we still need to test for
`requires-python` compatibility when selecting distributions.
This could use more testing, but it feels like an area where `packse`
would be more productive than writing PyPI tests.
Closes https://github.com/astral-sh/puffin/issues/406.
Part of https://github.com/astral-sh/puffin/issues/214
Adds a `project: Option<PackageName>` to the `Manifest`, `Resolver`, and
`RequirementsSpecification`.
To populate an optional `name` for `PubGubPackage::Root`.
I'll work on removing the version number next.
Should we consider using the parent directory name when a
`pyproject.toml` file is not present?
The normalized name abstractions were not consistently, this PR uses
them where they were previously missing:
* `WheelFilename::distribution`
* `Requirement::name`
* `Requirement::extras`
* `Metadata21::name`
* `Metadata21::provides_dist`
With `puffin-package` depending on `pep508_rs` this would be cyclical
crate dependency, so `puffin-normalize` gets split out from
`puffin-package`.
`DistInfoName` has the same task and semantics as `PackageName`, so it's
merged into the latter.
`PackageName` and `ExtraName` documentation is moved onto the type and
their constructors are called `new` instead of `normalize`. We now use
these constructors rarely enough the implicit allocation by
`to_string()` shouldn't matter anymore, while more actual cloning
becomes visible.
## Summary
This PR adds support for resolving and installing dependencies via
direct URLs, like:
```
werkzeug @ 960bb4017c4aed12b5ed8b78e0153e/Werkzeug-2.0.0-py3-none-any.whl
```
These are fairly common (e.g., with `torch`), but you most often see
them as Git dependencies.
Broadly, structs like `RemoteDistribution` and friends are now enums
that can represent either registry-based dependencies or URL-based
dependencies:
```rust
/// A built distribution (wheel) that exists as a remote file (e.g., on `PyPI`).
#[derive(Debug, Clone)]
#[allow(clippy::large_enum_variant)]
pub enum RemoteDistribution {
/// The distribution exists in a registry, like `PyPI`.
Registry(PackageName, Version, File),
/// The distribution exists at an arbitrary URL.
Url(PackageName, Url),
}
```
In the resolver, we now allow packages to take on an extra, optional
`Url` field:
```rust
#[derive(Debug, Clone, Eq, Derivative)]
#[derivative(PartialEq, Hash)]
pub enum PubGrubPackage {
Root,
Package(
PackageName,
Option<DistInfoName>,
#[derivative(PartialEq = "ignore")]
#[derivative(PartialOrd = "ignore")]
#[derivative(Hash = "ignore")]
Option<Url>,
),
}
```
However, for the purpose of version satisfaction, we ignore the URL.
This allows for the URL dependency to satisfy the transitive request in
cases like:
```
flask==3.0.0
werkzeug @ 254c3e9b5f5941e900b71206e6313b/werkzeug-3.0.1-py3-none-any.whl
```
There are a couple limitations in the current approach:
- The caching for remote URLs is done separately in the resolver vs. the
installer. I decided not to sweat this too much... We need to figure out
caching holistically.
- We don't support any sort of time-based cache for remote URLs -- they
just exist forever. This will be a problem for URL dependencies, where
we need some way to evict and refresh them. But I've deferred it for
now.
- I think I need to redo how this is modeled in the resolver, because
right now, we don't detect a variety of invalid cases, e.g., providing
two different URLs for a dependency, asking for a URL dependency and a
_different version_ of the same dependency in the list of first-party
dependencies, etc.
- (We don't yet support VCS dependencies.)