test: strengthen FileFilter validation

Author: ParthAggarwal16

application/tests/harvester_test/file_filter_test.py

@@ -112,6 +112,10 @@ def test_default_instance_isolation(self):
             second.exclude_patterns,
         )
 
+    def test_empty_extension_raises(self):
+        with self.assertRaises(ValueError):
+            FileFilter(allowed_extensions={""})
+
 
 if __name__ == "__main__":
     unittest.main()

application/utils/harvester/file_filter.py

@@ -54,6 +54,9 @@ def _validate_patterns(self) -> None:
         if any(not pattern for pattern in self.exclude_patterns):
             raise ValueError("Exclude pattern cannot be empty")
 
+        if any(not extension for extension in self.allowed_extensions):
+            raise ValueError("Allowed extension cannot be empty")
+
     def _normalize_path(self, file_path: str) -> str:
         return PurePosixPath(file_path).as_posix()