Fixed #1801: CLI bug (--exend-skip-glob, overrides instead of extending).

Author: timothycrosley

CHANGELOG.md

@@ -6,6 +6,7 @@ Find out more about isort's release policy [here](https://pycqa.github.io/isort/
 
 ### 5.10.0 TBD
   - Implemented #1796: Switch to `tomli` for pyproject.toml configuration loader.
+  - Fixed #1801: CLI bug (--exend-skip-glob, overrides instead of extending).
 
 #### Potentially breaking changes:
   - Fixed #1785: `_ast` module incorrectly excluded from stdlib definition.

isort/main.py

@@ -346,7 +346,7 @@ def _build_arg_parser() -> argparse.ArgumentParser:
     target_group.add_argument(
         "--extend-skip-glob",
         help="Additional files that isort should skip over (extending --skip-glob).",
-        dest="skip_glob",
+        dest="extend_skip_glob",
         action="append",
     )
     target_group.add_argument(