Undo a Perforce changelist

I had this problem with Perforce where I accidentally Reconciled my offline work with all the files in /bin and /obj folders, resulting in a huge 6000+ file changelist. OK, simple one button mistake, surely there must be some one button undoing what I just did. It appears there is not.

In order to fix this I have to follow these steps:

1. Change the settings of Perforce to show files even in changelists larger than 1000 items (the default value)
2. Select by hand in the changelist window the files from obj and bin folders and using Revert on them
3. Revert the few other files that were unwanted in the changelist, like .suo and .user files - note that Revert on added files doesn't delete them, it just unadds them
4. Create a file with paths to ignore and then use p4 set P4IGNORE=<filename> for future reconcile work

What didn't work was adding a filename or path filter when visualizing the changelist, since that is a changelist filter, not a files filter. It will show you changelists that have files that contain the pattern, but not filter the files inside the changelists themselves.

For reference, the p4ignore file I used looked like this:

p4ignore
bin/Debug
obj/Debug
*.suo
*.user

Note that I also added the p4ignore file itself, although the file was not in any Perforce repository (yet).

"But, Siderite, you should use Git (or whatever source control is the newest fad at the moment)!" Wish that could, my friend, wish that I could.