Flake8 Extension to enforce better comma placement.

Usage

If you are using flake8 it's as easy as:

pip install flake8-commas

Now you can avoid those annoying merge conflicts on dictionary and list diffs.

Errors

Different versions of python require commas in different places. Ignore the errors for languages you don't use in your flake8 config:

Examples

lookup_table = {
    'key1': 'value',
    'key2': 'something'  # <-- missing a trailing comma
}

json_data = json.dumps({
    "key": "value",
}),                      # <-- incorrect trailing comma. json_data is now a tuple. Likely by accident.