Sort logic and SORT_TYPES.None question

[plweil]

Issue Type

• Question (this is similar to Feature: prevent reset sorting after third click on column header #864)

Expected Behavior

Assume this is not multi-column sorting.
I would expect that clicking the sort button in a previously unsorted column A would sort the table by column A ascending.

Next, clicking Column A (sorted ascending) would sort the table by Column A descending.

Clicking the button subsequently would alternate between ascending and descending.

Sorting the table by a different column would leave Column A unsorted.

Actual Behavior

Instead, the third click sets the column sort type to none". What is "none", and what does it do? The only thing that should turn sorting off for a column that has been sorted is to sort by a different column.

I don't understand the logic of applying SORT_TYPES.None to a column that has been clicked three times. This has major ramifications for the sort icon, the use of aria-sort on headings, and the sort button name.

[xaksis]

The reason for the 3rd mode for sorting is to reset the table to its original order. Otherwise, there is no way to get back to the original state once any sort is performed.
Relevant ticket: #794