uv/tests: add regression test for echo pendulum | uv pip compile - (a…

…stral-sh#2693)

I stumbled across this when writing tests for
`--emit-marker-expressions`. Namely, I observed that in CI, the `tzdata`
dependency of `pendulum` wasn't included in the `requirements.txt`
output on Windows.

@konstin [suggested] that this was a bug, so I've created a test for it.
In particular, it looks like [`tzdata` is an unconditional dependency of
`pendulum`][tzdata-unconditional].

[suggested]:
astral-sh#2651 (comment)
[tzdata-unconditional]:
https://inspector.pypi.io/project/pendulum/3.0.0/packages/67/5e/e646afbd1632bfbacdae79289d7d5879efdeeb5f5e58327bc5c698731107/pendulum-3.0.0-cp310-none-win_amd64.whl/pendulum-3.0.0.dist-info/METADATA#line.12

crates/uv/tests/common/mod.rs

@@ -417,6 +417,10 @@ pub fn run_and_format<'a>(
         }
     }
 
+    // This is a heuristic filter meant to try and make *most* of our tests
+    // pass whether it's on Windows or Unix. In particular, there are some very
+    // common Windows-only dependencies that, when removed from a resolution,
+    // cause the set of dependencies to be the same across platforms.
     if cfg!(windows) && windows_filters {
         // The optional leading +/- is for install logs, the optional next line is for lock files
         let windows_only_deps = [

crates/uv/tests/pip_compile.rs

@@ -6294,3 +6294,37 @@ fn emit_marker_expression_pypy() -> Result<()> {
 
     Ok(())
 }
+
+#[test]
+fn pendulum_no_tzdata_on_windows() -> Result<()> {
+    let context = TestContext::new("3.12");
+    let requirements_in = context.temp_dir.child("requirements.in");
+    requirements_in.write_str("pendulum")?;
+
+    uv_snapshot!(
+        context.filters(),
+        windows_filters=false,
+        context.compile().arg("requirements.in"), @r###"
+    success: true
+    exit_code: 0
+    ----- stdout -----
+    # This file was autogenerated by uv via the following command:
+    #    uv pip compile --cache-dir [CACHE_DIR] --exclude-newer 2024-03-25T00:00:00Z requirements.in
+    pendulum==3.0.0
+    python-dateutil==2.9.0.post0
+        # via
+        #   pendulum
+        #   time-machine
+    six==1.16.0
+        # via python-dateutil
+    time-machine==2.14.1
+        # via pendulum
+    tzdata==2024.1
+        # via pendulum
+
+    ----- stderr -----
+    Resolved 5 packages in [TIME]
+    "###);
+
+    Ok(())
+}