Every Increase Failed With 422, and the User Saw Nothing At All
QC’s bug report had two sentences. Clicking Increase in the adjust-quantity modal did nothing. Clicking it again also did nothing. “Nothing” is the worst symptom to be handed. A crash leaves a stack trace, a wrong result leaves a wrong number; an unchanged screen leaves no starting point at all. What was actually broken The screen is an internal admin panel for a promotions backend. An operator opens a modal to adjust the allocated quantity for one SKU in one campaign. The modal has two tabs — Increase and Decrease — and one submit button. Whichever tab is active decides which operation is sent. ...