🐛 fix(discovery): match prerelease versions against major.minor specs (#48)

Author: gaborbernat

src/python_discovery/_py_info.py

@@ -469,12 +469,24 @@ def _satisfies_version_specifier(self, spec: PythonSpec) -> bool:
         if spec.version_specifier is None:  # pragma: no cover
             return True
         version_info = self.version_info
-        release = f"{version_info.major}.{version_info.minor}.{version_info.micro}"
-        if version_info.releaselevel != "final":
-            suffix = {"alpha": "a", "beta": "b", "candidate": "rc"}.get(version_info.releaselevel)
-            if suffix is not None:  # pragma: no branch # releaselevel is always alpha/beta/candidate here
+        for specifier in spec.version_specifier:
+            assert specifier.version is not None  # noqa: S101
+            numeric_version = specifier.version_str
+            for prefix in ("rc", "b", "a"):
+                if prefix in numeric_version:
+                    numeric_version = numeric_version.split(prefix)[0]
+                    break
+            precision = numeric_version.count(".") + 1
+            release = ".".join(str(c) for c in [version_info.major, version_info.minor, version_info.micro][:precision])
+            if (
+                version_info.releaselevel != "final"
+                and (precision == 3 or specifier.version.pre_type is not None)  # noqa: PLR2004
+                and (suffix := {"alpha": "a", "beta": "b", "candidate": "rc"}.get(version_info.releaselevel))
+            ):
                 release = f"{release}{suffix}{version_info.serial}"
-        return spec.version_specifier.contains(release)
+            if not specifier.contains(release):
+                return False
+        return True
 
     _current_system = None
     _current = None

tests/test_py_info_extra.py

@@ -276,25 +276,29 @@ def test_satisfies_version_specifier_fails() -> None:
     assert CURRENT.satisfies(spec, impl_must_match=False) is False
 
 
-def test_satisfies_prerelease_version() -> None:
+@pytest.mark.parametrize(
+    ("version_info", "spec_str", "expected"),
+    [
+        pytest.param(VersionInfo(3, 14, 0, "alpha", 1), ">=3.14.0a1", True, id="alpha_match_exact"),
+        pytest.param(VersionInfo(3, 14, 0, "beta", 1), ">=3.14.0b1", True, id="beta_match_exact"),
+        pytest.param(VersionInfo(3, 14, 0, "candidate", 1), ">=3.14.0rc1", True, id="rc_match_exact"),
+        pytest.param(VersionInfo(3, 15, 0, "alpha", 6), ">=3.15", True, id="prerelease_match_major_minor"),
+        pytest.param(VersionInfo(3, 15, 0, "alpha", 6), ">=3.15.0", False, id="prerelease_not_match_full_precision"),
+        pytest.param(VersionInfo(3, 15, 0, "alpha", 5), "<3.15.0a6", True, id="earlier_prerelease_less_than"),
+        pytest.param(VersionInfo(3, 15, 0, "alpha", 6), "<3.15.0a6", False, id="prerelease_not_less_than_itself"),
+        pytest.param(VersionInfo(3, 15, 0, "alpha", 6), ">=3.15.0a6", True, id="prerelease_match_itself"),
+        pytest.param(VersionInfo(3, 15, 0, "alpha", 6), ">=3.15.0a7", False, id="prerelease_not_match_later"),
+        pytest.param(VersionInfo(3, 15, 0, "final", 0), ">=3.15.0a6", True, id="final_greater_than_prerelease"),
+        pytest.param(VersionInfo(3, 15, 0, "final", 0), "<3.15.0a6", False, id="final_not_less_than_prerelease"),
+        pytest.param(VersionInfo(3, 15, 0, "final", 0), ">=3.15", True, id="final_match_major_minor"),
+        pytest.param(VersionInfo(3, 15, 1, "alpha", 1), ">=3.15.0", True, id="later_micro_prerelease_match"),
+    ],
+)
+def test_satisfies_version_specifier_prerelease(version_info: VersionInfo, spec_str: str, expected: bool) -> None:
     info = copy.deepcopy(CURRENT)
-    info.version_info = VersionInfo(3, 14, 0, "alpha", 1)
-    spec = PythonSpec.from_string_spec(">=3.14.0a1")
-    assert info.satisfies(spec, impl_must_match=False) is True
-
-
-def test_satisfies_prerelease_beta() -> None:
-    info = copy.deepcopy(CURRENT)
-    info.version_info = VersionInfo(3, 14, 0, "beta", 1)
-    spec = PythonSpec.from_string_spec(">=3.14.0b1")
-    assert info.satisfies(spec, impl_must_match=False) is True
-
-
-def test_satisfies_prerelease_candidate() -> None:
-    info = copy.deepcopy(CURRENT)
-    info.version_info = VersionInfo(3, 14, 0, "candidate", 1)
-    spec = PythonSpec.from_string_spec(">=3.14.0rc1")
-    assert info.satisfies(spec, impl_must_match=False) is True
+    info.version_info = version_info
+    spec = PythonSpec.from_string_spec(spec_str)
+    assert info.satisfies(spec, impl_must_match=False) is expected
 
 
 def test_satisfies_path_not_abs_basename_match() -> None: