bpo-33254: do not return an empty list when asking for the contents of a namespace package (GH-6467)
diff --git a/Lib/importlib/abc.py b/Lib/importlib/abc.py
index d2f4509..dbdd5bf 100644
--- a/Lib/importlib/abc.py
+++ b/Lib/importlib/abc.py
@@ -381,8 +381,8 @@
@abc.abstractmethod
def contents(self):
- """Return an iterator of strings over the contents of the package."""
- return iter([])
+ """Return an iterable of strings over the contents of the package."""
+ return []
_register(ResourceReader, machinery.SourceFileLoader)
diff --git a/Lib/importlib/resources.py b/Lib/importlib/resources.py
index e565427..4d70186 100644
--- a/Lib/importlib/resources.py
+++ b/Lib/importlib/resources.py
@@ -9,7 +9,7 @@
from io import BytesIO, TextIOWrapper
from pathlib import Path
from types import ModuleType
-from typing import Iterator, Optional, Set, Union # noqa: F401
+from typing import Iterable, Iterator, Optional, Set, Union # noqa: F401
from typing import cast
from typing.io import BinaryIO, TextIO
from zipimport import ZipImportError
@@ -44,8 +44,7 @@
If the resulting string contains path separators, an exception is raised.
"""
- str_path = str(path)
- parent, file_name = os.path.split(str_path)
+ parent, file_name = os.path.split(path)
if parent:
raise ValueError('{!r} must be only a file name'.format(path))
else:
@@ -228,8 +227,8 @@
return path.is_file()
-def contents(package: Package) -> Iterator[str]:
- """Return the list of entries in 'package'.
+def contents(package: Package) -> Iterable[str]:
+ """Return an iterable of entries in 'package'.
Note that not all entries are resources. Specifically, directories are
not considered resources. Use `is_resource()` on each entry returned here
@@ -238,15 +237,15 @@
package = _get_package(package)
reader = _get_resource_reader(package)
if reader is not None:
- yield from reader.contents()
- return
+ return reader.contents()
# Is the package a namespace package? By definition, namespace packages
# cannot have resources. We could use _check_location() and catch the
# exception, but that's extra work, so just inline the check.
- if package.__spec__.origin is None or not package.__spec__.has_location:
- return []
- package_directory = Path(package.__spec__.origin).parent
- yield from os.listdir(str(package_directory))
+ elif package.__spec__.origin is None or not package.__spec__.has_location:
+ return ()
+ else:
+ package_directory = Path(package.__spec__.origin).parent
+ return os.listdir(package_directory)
# Private implementation of ResourceReader and get_resource_reader() for
diff --git a/Lib/test/test_importlib/test_resource.py b/Lib/test/test_importlib/test_resource.py
index d717e1d..b076860 100644
--- a/Lib/test/test_importlib/test_resource.py
+++ b/Lib/test/test_importlib/test_resource.py
@@ -131,10 +131,9 @@
class NamespaceTest(unittest.TestCase):
- def test_namespaces_cant_have_resources(self):
- contents = set(resources.contents(
- 'test.test_importlib.data03.namespace'))
- self.assertEqual(len(contents), 0)
+ def test_namespaces_cannot_have_resources(self):
+ contents = resources.contents('test.test_importlib.data03.namespace')
+ self.assertFalse(list(contents))
# Even though there is a file in the namespace directory, it is not
# considered a resource, since namespace packages can't have them.
self.assertFalse(resources.is_resource(