Full item stacks do not swap with smaller stack on cursor

In any inventory, when holding a full stack of an item in the cursor, clicking on a partial stack of the same item swaps the clicked stack with the cursor stack (maybe not technically, but functionally), however when holding a partial stack of an item in the cursor, clicking on a full stack of the same item does nothing.

What I expected to happen was...:
Clicking a full stack with the partial stack should swap the stacks, as there is nothing else to do.

What actually happened was...:
Nothing happens when clicked.
**

Steps to Reproduce:
1. Put two stacks a stackable item in the inventory.
2. Split one stack, and click on the other full stack with the half stack in the cursor.