mypy: Fix typing around importlib.resources

mypy was correct here: _path doesn't always return a pathlib.Path, it's why we need to handle that in _glob().

1 files changed, 14 insertions, 9 deletions

diff --git a/qutebrowser/utils/resources.py b/qutebrowser/utils/resources.py
index f561d6747..f9b59661e 100644
--- a/qutebrowser/utils/resources.py
+++ b/qutebrowser/utils/resources.py
@@ -24,19 +24,28 @@ import sys
 import contextlib
 import posixpath
 import pathlib
-from typing import Iterator, Iterable
+from typing import Iterator, Iterable, Union
 
 
 # We cannot use the stdlib version on 3.7-3.8 because we need the files() API.
 if sys.version_info >= (3, 9):
     import importlib.resources as importlib_resources
+    from importlib.abc import Traversable
 else:  # pragma: no cover
     import importlib_resources
+    from importlib_resources.abc import Traversable
 
 import qutebrowser
 _cache = {}
 
-def _path(filename: str) -> pathlib.Path:
+
+# Unfortunately, we can't tell mypy about this also possibly being a
+# zipfile.Path because we set "python_version = 3.6" in .mypy.ini, but the
+# zipfile stubs (correctly) only declare zipfile.Path with Python 3.8...
+_ResourceType = Union[Traversable, pathlib.Path]
+
+
+def _path(filename: str) -> _ResourceType:
     """Get a pathlib.Path object for a resource."""
     assert not posixpath.isabs(filename), filename
     assert os.path.pardir not in filename.split(posixpath.sep), filename
@@ -64,7 +73,7 @@ def _keyerror_workaround() -> Iterator[None]:
 
 
 def _glob(
-    resource_path: pathlib.Path,
+    resource_path: _ResourceType,
     subdir: str,
     ext: str,
 ) -> Iterable[str]:
@@ -79,12 +88,8 @@ def _glob(
     if isinstance(resource_path, pathlib.Path):
         for full_path in glob_path.glob(f'*{ext}'):  # . is contained in ext
             yield full_path.relative_to(resource_path).as_posix()
-    else:  # zipfile.Path or importlib_resources compat object
-        # Unfortunately, we can't tell mypy about resource_path being of type
-        # Union[pathlib.Path, zipfile.Path] because we set "python_version = 3.6" in
-        # .mypy.ini, but the zipfile stubs (correctly) only declare zipfile.Path with
-        # Python 3.8...
-        assert glob_path.is_dir(), glob_path  # type: ignore[unreachable]
+    else:  # zipfile.Path or importlib_resources.abc.Traversable
+        assert glob_path.is_dir(), glob_path
         for subpath in glob_path.iterdir():
             if subpath.name.endswith(ext):
                 yield posixpath.join(subdir, subpath.name)