Restore lenience in MultiplexedPath.joinpath for missing directories

CHANGES.rst

@@ -1,3 +1,10 @@
+v5.8.1
+======
+
+* #253: In ``MultiplexedPath``, restore expectation that
+  a compound path with a non-existent directory does not
+  raise an exception.
+
 v5.8.0
 ======
 

importlib_resources/readers.py

@@ -85,13 +85,10 @@ def is_file(self):
     def joinpath(self, *descendants):
         try:
             return super().joinpath(*descendants)
-        except abc.TraversalError as exc:
-            # One of the paths didn't resolve.
-            msg, target, names = exc.args
-            if names:  # pragma: nocover
-                raise
-            # It was the last; construct result with the first path.
-            return self._paths[0].joinpath(target)
+        except abc.TraversalError:
+            # One of the paths did not resolve (a directory does not exist).
+            # Just return something that will not exist.
+            return self._paths[0].joinpath(*descendants)
 
     def open(self, *args, **kwargs):
         raise FileNotFoundError(f'{self} is not a file')

importlib_resources/tests/test_reader.py

@@ -77,6 +77,10 @@ def test_join_path(self):
         )
         self.assertEqual(path.joinpath(), path)
 
+    def test_join_path_compound(self):
+        path = MultiplexedPath(self.folder)
+        assert not path.joinpath('imaginary/foo.py').exists()
+
     def test_repr(self):
         self.assertEqual(
             repr(MultiplexedPath(self.folder)),