Add $FZF_CTRL_R_OPTS for overriding the default options for CTRL-R

Close #526

shell/key-bindings.bash

@@ -49,7 +49,7 @@ __fzf_history__() (
   shopt -u nocaseglob nocasematch
   line=$(
     HISTTIMEFORMAT= history |
-    $(__fzfcmd) +s --tac +m -n2..,.. --tiebreak=index --toggle-sort=ctrl-r |
+    $(__fzfcmd) +s --tac +m -n2..,.. --tiebreak=index --toggle-sort=ctrl-r $FZF_CTRL_R_OPTS |
     \grep '^ *[0-9]') &&
     if [[ $- =~ H ]]; then
       sed 's/^ *\([0-9]*\)\** .*/!\1/' <<< "$line"

shell/key-bindings.fish

@@ -27,7 +27,7 @@ function fzf_key_bindings
   end
 
   function __fzf_ctrl_r
-    history | eval (__fzfcmd) +s +m --tiebreak=index --toggle-sort=ctrl-r > $TMPDIR/fzf.result
+    history | eval (__fzfcmd) +s +m --tiebreak=index --toggle-sort=ctrl-r $FZF_CTRL_R_OPTS > $TMPDIR/fzf.result
     and commandline (cat $TMPDIR/fzf.result)
     commandline -f repaint
     rm -f $TMPDIR/fzf.result

shell/key-bindings.zsh

@@ -38,7 +38,7 @@ bindkey '\ec' fzf-cd-widget
 # CTRL-R - Paste the selected command from history into the command line
 fzf-history-widget() {
   local selected num
-  selected=( $(fc -l 1 | $(__fzfcmd) +s --tac +m -n2..,.. --tiebreak=index --toggle-sort=ctrl-r -q "${LBUFFER//$/\\$}") )
+  selected=( $(fc -l 1 | $(__fzfcmd) +s --tac +m -n2..,.. --tiebreak=index --toggle-sort=ctrl-r $FZF_CTRL_R_OPTS -q "${LBUFFER//$/\\$}") )
   if [ -n "$selected" ]; then
     num=$selected[1]
     if [ -n "$num" ]; then