Extract tests for Python 3.9 compatibility into their own file

Author: abravalheri

tests/test_integration.py

@@ -8,10 +8,7 @@
 from importlib_metadata import (
     MetadataPathFinder,
     _compat,
-    distribution,
     distributions,
-    entry_points,
-    metadata,
     version,
 )
 
@@ -48,68 +45,6 @@ def __getattribute__(self, name):
         _compat.disable_stdlib_finder()
 
 
-class OldStdlibFinderTests(fixtures.DistInfoPkgOffPath, unittest.TestCase):
-    def setUp(self):
-        python_version = sys.version_info[:2]
-        if python_version < (3, 8) or python_version > (3, 9):
-            self.skipTest("Tests specific for Python 3.8/3.9")
-        super().setUp()
-
-    def _meta_path_finder(self):
-        from importlib.metadata import (
-            Distribution,
-            DistributionFinder,
-            PathDistribution,
-        )
-        from importlib.util import spec_from_file_location
-
-        path = pathlib.Path(self.site_dir)
-
-        class CustomDistribution(Distribution):
-            def __init__(self, name, path):
-                self.name = name
-                self._path_distribution = PathDistribution(path)
-
-            def read_text(self, filename):
-                return self._path_distribution.read_text(filename)
-
-            def locate_file(self, path):
-                return self._path_distribution.locate_file(path)
-
-        class CustomFinder:
-            @classmethod
-            def find_spec(cls, fullname, _path=None, _target=None):
-                candidate = pathlib.Path(path, *fullname.split(".")).with_suffix(".py")
-                if candidate.exists():
-                    return spec_from_file_location(fullname, candidate)
-
-            @classmethod
-            def find_distributions(self, context=DistributionFinder.Context()):
-                for dist_info in path.glob("*.dist-info"):
-                    yield PathDistribution(dist_info)
-                    name, _, _ = str(dist_info).partition("-")
-                    yield CustomDistribution(name + "_custom", dist_info)
-
-        return CustomFinder
-
-    def test_compatibility_with_old_stdlib_path_distribution(self):
-        """
-        Given a custom finder that uses Python 3.8/3.9 importlib.metadata is installed,
-        when importlib_metadata functions are called, there should be no exceptions.
-        Ref python/importlib_metadata#396.
-        """
-        self.fixtures.enter_context(fixtures.install_finder(self._meta_path_finder()))
-
-        assert list(distributions())
-        assert distribution("distinfo_pkg")
-        assert distribution("distinfo_pkg_custom")
-        assert version("distinfo_pkg") > "0"
-        assert version("distinfo_pkg_custom") > "0"
-        assert list(metadata("distinfo_pkg"))
-        assert list(metadata("distinfo_pkg_custom"))
-        assert list(entry_points(group="entries"))
-
-
 class DistSearch(unittest.TestCase):
     def test_search_dist_dirs(self):
         """

tests/test_py39compat.py

@@ -0,0 +1,74 @@
+import sys
+import unittest
+import pathlib
+
+from . import fixtures
+from importlib_metadata import (
+    distribution,
+    distributions,
+    entry_points,
+    metadata,
+    version,
+)
+
+
+class OldStdlibFinderTests(fixtures.DistInfoPkgOffPath, unittest.TestCase):
+    def setUp(self):
+        python_version = sys.version_info[:2]
+        if python_version < (3, 8) or python_version > (3, 9):
+            self.skipTest("Tests specific for Python 3.8/3.9")
+        super().setUp()
+
+    def _meta_path_finder(self):
+        from importlib.metadata import (
+            Distribution,
+            DistributionFinder,
+            PathDistribution,
+        )
+        from importlib.util import spec_from_file_location
+
+        path = pathlib.Path(self.site_dir)
+
+        class CustomDistribution(Distribution):
+            def __init__(self, name, path):
+                self.name = name
+                self._path_distribution = PathDistribution(path)
+
+            def read_text(self, filename):
+                return self._path_distribution.read_text(filename)
+
+            def locate_file(self, path):
+                return self._path_distribution.locate_file(path)
+
+        class CustomFinder:
+            @classmethod
+            def find_spec(cls, fullname, _path=None, _target=None):
+                candidate = pathlib.Path(path, *fullname.split(".")).with_suffix(".py")
+                if candidate.exists():
+                    return spec_from_file_location(fullname, candidate)
+
+            @classmethod
+            def find_distributions(self, context=DistributionFinder.Context()):
+                for dist_info in path.glob("*.dist-info"):
+                    yield PathDistribution(dist_info)
+                    name, _, _ = str(dist_info).partition("-")
+                    yield CustomDistribution(name + "_custom", dist_info)
+
+        return CustomFinder
+
+    def test_compatibility_with_old_stdlib_path_distribution(self):
+        """
+        Given a custom finder that uses Python 3.8/3.9 importlib.metadata is installed,
+        when importlib_metadata functions are called, there should be no exceptions.
+        Ref python/importlib_metadata#396.
+        """
+        self.fixtures.enter_context(fixtures.install_finder(self._meta_path_finder()))
+
+        assert list(distributions())
+        assert distribution("distinfo_pkg")
+        assert distribution("distinfo_pkg_custom")
+        assert version("distinfo_pkg") > "0"
+        assert version("distinfo_pkg_custom") > "0"
+        assert list(metadata("distinfo_pkg"))
+        assert list(metadata("distinfo_pkg_custom"))
+        assert list(entry_points(group="entries"))