Sometimes users prefer . instead of source

So only check for file name

install

@@ -337,7 +337,11 @@ append_line() {
   echo "Update $2:"
   echo "  - $1"
   [ -f "$2" ] || touch "$2"
-  line=$(\grep -nF "$1" "$2" | sed 's/:.*//')
+  if [ $# -lt 3 ]; then
+    line=$(\grep -nF "$1" "$2" | sed 's/:.*//')
+  else
+    line=$(\grep -nF "$3" "$2" | sed 's/:.*//')
+  fi
   if [ -n "$line" ]; then
     echo "    - Already exists (line #$line)"
   else
@@ -349,7 +353,7 @@ append_line() {
 
 echo
 for shell in bash zsh; do
-  append_line "source ~/.fzf.${shell}" ~/.${shell}rc
+  append_line "source ~/.fzf.${shell}" ~/.${shell}rc "~/.fzf.${shell}"
 done
 
 if [ $key_bindings -eq 0 -a $has_fish -eq 1 ]; then