multisort with custom sortType functions not working

[vladatnyc]

Hi all. I have data with two columns and I'd like to sort on both columns using a custom sorter function. I set this up using the sortType param on the column object, and pass initialState.sortBy an array with the two sort objects( {id:column}). However, it seems that only the first column listed is getting sorted by. This is limited to using custom sorting functions. If I remove the sortType options on the column objects those and just let it sort alphabetically everything works as expected.

Here is a codepen with the problem: https://codepen.io/vladatnyc/pen/KKNzKaM.

Any help would be much appreciated.