tests: run both pip and uv tests

Signed-off-by: Henry Schreiner <[email protected]>

README.md

@@ -64,8 +64,10 @@ To use the [pre-commit](https://pre-commit.com) integration, put this in your
 This requires your build dependencies, but in doing so, it can cache the
 environment, making it quite fast. The installation is handled by pre-commit;
 see [`pre-commit-uv`](https://pypi.org/p/pre-commit-uv) if you want to try to
-optimize the initial setup. If you don't mind slower runs and don't want to
-require a build dependency listing:
+optimize the initial setup. If uv is present (including in your
+`additional_dependencies`), the build will be slightly faster, as uv is used to
+do the build. If you don't mind slower runs and don't want to require a build
+dependency listing:
 
 ```yaml
 - repo: https://github.com/henryiii/check-sdist

tests/test_downstream.py

@@ -7,17 +7,27 @@
 
 from check_sdist.__main__ import compare
 from check_sdist._compat import tomllib
+from check_sdist.sdist import get_uv
 
 DIR = Path(__file__).parent.resolve()
 
 with DIR.joinpath("downstream.toml").open("rb") as f:
     packages = tomllib.load(f)["packages"]
 
 
+@pytest.mark.parametrize(
+    "installer",
+    [
+        pytest.param(
+            "uv", marks=pytest.mark.skipif(get_uv() is None, reason="uv not found")
+        ),
+        "pip",
+    ],
+)
 @pytest.mark.parametrize(
     ("repo", "ref", "fail"), [(x["repo"], x["ref"], x.get("fail", 0)) for x in packages]
 )
-def test_packages(repo, ref, fail, tmp_path, monkeypatch):
+def test_packages(repo, ref, fail, tmp_path, monkeypatch, installer):
     monkeypatch.chdir(tmp_path)
     cmd = [
         "git",
@@ -29,4 +39,4 @@ def test_packages(repo, ref, fail, tmp_path, monkeypatch):
     ]
     subprocess.run(cmd, check=True)
     package_path = tmp_path / repo.split("/")[1]
-    assert compare(package_path, isolated=True) == fail
+    assert compare(package_path, isolated=True, installer=installer) == fail