[zsh] Do not change LBUFFER on empty selection (CTRL-R)

shell/key-bindings.zsh

@@ -38,13 +38,15 @@ fzf-history-widget() {
   local selected restore_no_bang_hist
   if selected=$(fc -l 1 | $(__fzfcmd) +s --tac +m -n2..,.. --tiebreak=index --toggle-sort=ctrl-r -q "$LBUFFER"); then
     num=$(echo "$selected" | head -1 | awk '{print $1}' | sed 's/[^0-9]//g')
-    LBUFFER=!$num
-    if setopt | grep nobanghist > /dev/null; then
-      restore_no_bang_hist=1
-      unsetopt no_bang_hist
+    if [ -n "$num" ]; then
+      LBUFFER=!$num
+      if setopt | grep nobanghist > /dev/null; then
+        restore_no_bang_hist=1
+        unsetopt no_bang_hist
+      fi
+      zle expand-history
+      [ -n "$restore_no_bang_hist" ] && setopt no_bang_hist
     fi
-    zle expand-history
-    [ -n "$restore_no_bang_hist" ] && setopt no_bang_hist
   fi
   zle redisplay
 }