Yesterday I wrote some code to hide the Trash location in our document picker when it’s empty. Today, I got a bug report that attempting to add or remove a cloud storage location in the document picker would now crash with an exception thrown by
UITableView. These didn’t sound all that related other than timing and both involving the document picker.
And at first, all the evidence told me they were not related. But thanks to a combination of overlapping bugs it took me over an hour, a fair bit of disassembly, and some moral support from my coworker Jake to track down the origin of the bug.