distribution-types: allow RegistrySourceDist to have wheels attached to it (#3610)

Following from #3595, we'd like wheels to make their way into the lock
file even if the current environment selects an sdist. With #3595, this
didn't happen:

$ cargo run -p uv -- pip compile -p3.10 <(echo psycopg2)
--unstable-uv-lock-file
    $ cat uv.lock
    version = 1

    [[distribution]]
    name = "psycopg2"
    version = "2.9.9"
    source = "registry+https://pypi.org/simple"

    [distribution.sdist]
url =
"dc6acaf46d/psycopg2-2.9.9.tar.gz"
hash =
"sha256:d1454bde93fb1e224166811694d600e746430c006fbb031ea06ecc2ea41bf156"

The above example uses `psycopg2`, which has an sdist and wheels only on
Windows. Since I ran the above on Linux, an sdist was selected. But no
wheels appeared in the lock file.

With this PR, wheels are now correctly plumbed through:

$ cargo run -p uv -- pip compile -p3.10 <(echo psycopg2)
--unstable-uv-lock-file
    $ cat uv.lock
    version = 1

    [[distribution]]
    name = "psycopg2"
    version = "2.9.9"
    source = "registry+https://pypi.org/simple"

    [distribution.sdist]
url =
"dc6acaf46d/psycopg2-2.9.9.tar.gz"
hash =
"sha256:d1454bde93fb1e224166811694d600e746430c006fbb031ea06ecc2ea41bf156"

    [[distribution.wheel]]
url =
"2767d96391/psycopg2-2.9.9-cp310-cp310-win32.whl"
hash =
"sha256:38a8dcc6856f569068b47de286b472b7c473ac7977243593a288ebce0dc89516"

    [[distribution.wheel]]
url =
"6572dec683/psycopg2-2.9.9-cp310-cp310-win_amd64.whl"
hash =
"sha256:426f9f29bde126913a20a96ff8ce7d73fd8a216cfb323b1f04da402d452853c3"

    [[distribution.wheel]]
url =
"1fc5b9d33c/psycopg2-2.9.9-cp311-cp311-win32.whl"
hash =
"sha256:ade01303ccf7ae12c356a5e10911c9e1c51136003a9a1d92f7aa9d010fb98372"

    [[distribution.wheel]]
url =
"5133dd3183/psycopg2-2.9.9-cp311-cp311-win_amd64.whl"
hash =
"sha256:121081ea2e76729acfb0673ff33755e8703d45e926e416cb59bae3a86c6a4981"

    [[distribution.wheel]]
url =
"f74ffe6b6f/psycopg2-2.9.9-cp312-cp312-win32.whl"
hash =
"sha256:d735786acc7dd25815e89cc4ad529a43af779db2e25aa7c626de864127e5a024"

    [[distribution.wheel]]
url =
"c4a26e1918/psycopg2-2.9.9-cp312-cp312-win_amd64.whl"
hash =
"sha256:a7653d00b732afb6fc597e29c50ad28087dcb4fbfb28e86092277a559ae4e693"

    [[distribution.wheel]]
url =
"ffeb9ac356/psycopg2-2.9.9-cp37-cp37m-win32.whl"
hash =
"sha256:5e0d98cade4f0e0304d7d6f25bbfbc5bd186e07b38eac65379309c4ca3193efa"

    [[distribution.wheel]]
url =
"0a39176d36/psycopg2-2.9.9-cp37-cp37m-win_amd64.whl"
hash =
"sha256:7e2dacf8b009a1c1e843b5213a87f7c544b2b042476ed7755be813eaf4e8347a"

    [[distribution.wheel]]
url =
"86b90d30c4/psycopg2-2.9.9-cp38-cp38-win32.whl"
hash =
"sha256:ff432630e510709564c01dafdbe996cb552e0b9f3f065eb89bdce5bd31fabf4c"

    [[distribution.wheel]]
url =
"c439b378ef/psycopg2-2.9.9-cp38-cp38-win_amd64.whl"
hash =
"sha256:bac58c024c9922c23550af2a581998624d6e02350f4ae9c5f0bc642c633a2d5e"

    [[distribution.wheel]]
url =
"5080c0e61a/psycopg2-2.9.9-cp39-cp39-win32.whl"
hash =
"sha256:c92811b2d4c9b6ea0285942b2e7cac98a59e166d59c588fe5cfe1eda58e72d59"

    [[distribution.wheel]]
url =
"ec73fe66d4/psycopg2-2.9.9-cp39-cp39-win_amd64.whl"
hash =
"sha256:de80739447af31525feddeb8effd640782cf5998e1a4e9192ebdf829717e3913"

Ref #3351

crates/distribution-types/src/lib.rs

@@ -221,6 +221,14 @@ pub struct RegistrySourceDist {
     pub filename: SourceDistFilename,
     pub file: Box<File>,
     pub index: IndexUrl,
+    /// When an sdist is selected, it may be the case that there were
+    /// available wheels too. There are many reasons why a wheel might not
+    /// have been chosen (maybe none available are compatible with the
+    /// current environment), but we still want to track that they exist. In
+    /// particular, for generating a universal lock file, we do not want to
+    /// skip emitting wheels to the lock file just because the host generating
+    /// the lock file didn't have any compatible wheels available.
+    pub wheels: Vec<RegistryBuiltWheel>,
 }
 
 /// A source distribution that exists at an arbitrary URL.

crates/distribution-types/src/prioritized_distribution.rs

@@ -346,12 +346,17 @@ impl PrioritizedDist {
     /// If this prioritized dist has an sdist, then this creates a source
     /// distribution.
     pub fn source_dist(&self) -> Option<RegistrySourceDist> {
-        // FIXME: We shouldn't be dropping all wheels here. When doing
-        // universal resolution, just because the host machine wants to use an
-        // sdist doesn't mean we should not put any wheels in the lock file.
-        // This probably means modifying RegistrySourceDist to look more like
-        // RegistryBuiltDist, but prioritizes the sdist.
-        let sdist = self.0.source.as_ref().map(|(sdist, _)| sdist.clone())?;
+        let mut sdist = self.0.source.as_ref().map(|(sdist, _)| sdist.clone())?;
+        assert!(
+            sdist.wheels.is_empty(),
+            "source distribution should not have any wheels yet"
+        );
+        sdist.wheels = self
+            .0
+            .wheels
+            .iter()
+            .map(|(wheel, _)| wheel.clone())
+            .collect();
         Some(sdist)
     }