So my new computer has a 2TB “hybrid” drive instead of the 512GB SSD I had in my laptop, so I thought I’d see if doing my video editing on the main drive instead of an external drive would be faster. The last video I did, from last weekend’s Electric City race, worked fine, although I didn’t really see any speed improvements. So yesterday when I went to start a new project the first thing I did was move the Electric City event/project from the Final Cut Pro (FCP) library on the main drive to the one on the external drive, and then start importing clips and editing on the new project. I did some editing and left it in the “transcoding and analysis” state overnight – editing is a lot smoother if you let it just finish those “background” tasks overnight, I’ve found.
But I wake up this morning to dire warnings about how I’ve run out of room on my main drive! So I did a “du” in the Movies folder, and discover that when I told Final Cut Pro to move the project, it did but it left a copy of the full project, including all the transcoded “optimized” files, in ~/Movies/FCP_Library.fcpbundle/__Trash/Electric\ City\ 2017-9B3Flz/. There doesn’t appear to be a menu item to empty that pseudo-trash, so I just did an rm -rf on it and now I’m down to 70% used.
After I did that, I discovered that Final Cut Pro will automatically empty __Trash when it exits, but it seems to me that cleaning up your old projects is a natural thing to do when starting a new one, so that’s just bad UX. Especially since when you tell it to move the project it returns a success immediately, but then it’s in the background tasks queue. So it was actually still going on when I was importing my clips last night, and so if I’d said to move the project then exited FCP it wouldn’t have had any trash to empty because it wouldn’t have finished moving.