[Redo] Behaviour after Unsuccessful Command

Background

For the redo command, it is stated in the UG that Note: If a new command (excluding redo or undo ) is executed after an undo, the redo history is cleared, and further redo will not be possible.

Test Case

The below commands in sequence addtag 2 t/pinktest undo cattag t/pinktest mentor (correctly leads to unsuccessful cattag-ing) redo

Expected Behaviour

I'm unsure if the UG means executed, successfully or not, then I cannot redo. So I was assuming I could still redo (i.e. the addtag 2 t/pinktest result would show)

Encountered Behaviour

Cannot redo as already at latest change

Remarks, if any

Medium as potentially could happen to the user, but can still use product. Feature flaw as feature not complete (?) yet, unless this was intended? I'm not sure

_{[original: nus-cs2103-AY2425S1/pe-interim#448] [original labels: severity.Medium type.FeatureFlaw]}

Team's Response

Thanks for pointing out. This is indeed a feature flaw in our product. As from the activity diagram in the DG, this behavior is expected. We assume that when users undo an operation, they are likely signaling a decision to discard the effects of the undone operation. Executing a new command suggests they are planning to move forward with a new intent or goal, rather than revisiting the undone operation.

In reality, if the user tries an invalid operation, it's unlikely they are thinking about redoing past undone operations in that moment—they are focused on resolving the issue with the current command. Hence, maybe we consider it as a flaw with low severity as it unlikely to cause inconvenience to users.

nus-cs2103-AY2425S1 / pe-dev-response