"require_tree argument must be a directory" rails 3.1.1 precompile assets
I ran into this exact same issue you described. My production server was Heroku (cedar stack). In my case the issue was that one of my:
require_tree ./mobileWas pointing to a legitimate directory, but this directory had no files. On dev it didn't matter but something about the production setup was resulting in the error, “require_tree argument must be a directory”.
Hopefully that helps.
require_tree must be given an existing folder, but git doesn't store empty folders,therefore when you deploy on heroku, those empty folders doesn't exist.
one trick is to add an empty .keep file to the folders you want to keep.