Stops theme breaking on root directory

fish_prompt.fish

@@ -10,12 +10,18 @@ set __toaster_color_lilac AE81FF
 
 function __toaster_color_echo
   set_color $argv[1]
+  if test (count $argv) -eq 2
     echo -n $argv[2]
   end
+end
 
 function __toaster_current_folder
+  if test $PWD = '/'
+    echo -n '/'
+  else
     echo -n $PWD | grep -o -E '[^\/]+$'
   end
+end
 
 function __toaster_git_status_codes
   echo (git status --porcelain ^/dev/null | sed -E 's/(^.{3}).*/\1/' | tr -d ' \n')