Abort soon if no swaps exist

dotfiles/bash/main.bashrc

     # 2015-07-10 06:10:48.603953758 +0200 ~/TODO.todo
     local swap="$HOME/.local/share/vim/swap"
     find "$swap" -type f \
-      | xargs stat -c "%y %n" \
+      | xargs -r stat -c "%y %n" \
       | sed "
             s| $swap/| |
             s|%|/|g