Stop recognizing files ending with .dist-info as dist

As proposed in PEP 376, dist-info distributions must be directories.

2 files changed, 22 insertions, 16 deletions

diff --git a/pkg_resources/__init__.py b/pkg_resources/__init__.py
index 15a4401a..4d15086f 100644
--- a/pkg_resources/__init__.py
+++ b/pkg_resources/__init__.py
@@ -2056,33 +2056,31 @@ def find_on_path(importer, path_item, only=False):
     filtered = (
         entry
         for entry in entries
-        if dist_factory(path_item, entry, only)
+        if dist_factory(entry, only)
     )
 
     # scan for .egg and .egg-info in directory
     path_item_entries = _by_version_descending(filtered)
     for entry in path_item_entries:
         fullpath = os.path.join(path_item, entry)
-        factory = dist_factory(path_item, entry, only)
+        factory = dist_factory(entry, only)
         for dist in factory(fullpath):
             yield dist
 
 
-def dist_factory(path_item, entry, only):
-    """
-    Return a dist_factory for a path_item and entry
-    """
+def dist_factory(entry, only):
+    """Return a dist_factory for the given entry."""
     lower = entry.lower()
-    is_meta = any(map(lower.endswith, ('.egg-info', '.dist-info')))
-    return (
-        distributions_from_metadata
-        if is_meta else
-        find_distributions
-        if not only and _is_egg_path(entry) else
-        resolve_egg_link
-        if not only and lower.endswith('.egg-link') else
-        NoDists()
-    )
+    if lower.endswith('.egg-info'):
+        return distributions_from_metadata
+    elif lower.endswith('.dist-info') and os.path.isdir(entry):
+        return distributions_from_metadata
+    elif not only and _is_egg_path(entry):
+        return find_distributions
+    elif not only and lower.endswith('.egg-link'):
+        return resolve_egg_link
+    else:
+        return NoDists()
 
 
 class NoDists:
diff --git a/pkg_resources/tests/test_pkg_resources.py b/pkg_resources/tests/test_pkg_resources.py
index 78281869..1c66dec0 100644
--- a/pkg_resources/tests/test_pkg_resources.py
+++ b/pkg_resources/tests/test_pkg_resources.py
@@ -330,6 +330,14 @@ def test_distribution_version_missing_undetected_path():
     assert msg == expected
 
 
+@pytest.mark.parametrize('only', [False, True])
+def test_dist_info_is_not_dir(tmp_path, only):
+    """Test path containing a file with dist-info extension."""
+    dist_info = tmp_path / 'foobar.dist-info'
+    dist_info.touch()
+    assert not pkg_resources.dist_factory(str(dist_info), only)
+
+
 class TestDeepVersionLookupDistutils:
     @pytest.fixture
     def env(self, tmpdir):