Fix join_filename return value when basename or extension are empty.

Author: fabiocaccamo

fsutil/__init__.py

@@ -881,8 +881,10 @@ def join_filename(basename: str, extension: str) -> str:
     """
     basename = basename.rstrip(".").strip()
     extension = extension.replace(".", "").strip()
-    filename = f"{basename}.{extension}"
-    return filename
+    if basename and extension:
+        filename = f"{basename}.{extension}"
+        return filename
+    return basename or extension
 
 
 def join_filepath(dirpath: PathIn, filename: str) -> str:

tests/test.py

@@ -805,6 +805,8 @@ def test_join_filename(self):
         self.assertEqual(fsutil.join_filename("Document", ".txt"), "Document.txt")
         self.assertEqual(fsutil.join_filename(" Document ", " txt "), "Document.txt")
         self.assertEqual(fsutil.join_filename("Document", " .txt "), "Document.txt")
+        self.assertEqual(fsutil.join_filename("Document", ""), "Document")
+        self.assertEqual(fsutil.join_filename("", "txt"), "txt")
 
     def test_join_filepath(self):
         self.assertEqual(