Unexpected Behavior - 7:Add
Insert _ at pos. 12
Name: abc
New name: abc_
Since there is no "pos 12" in the name, "abc", I would have expected the name abc to be unchanged.
Instead, it gets renamed to abc_.
So it's acting like an append (if the pos ## < len(name)).
But then the Suffix option would handle append, if you needed that. ...