diff --git a/contrib/zsh_completion b/contrib/zsh_completion
--- a/contrib/zsh_completion
+++ b/contrib/zsh_completion
@@ -624,7 +624,7 @@
 
   if [[ $state == 'diff_files' ]]
   then
-    if [[ -n $opt_args[-r] ]]
+    if [[ -n ${opt_args[(I)-r|--rev]} ]]
     then
       _hg_files && ret=0
     else
@@ -870,7 +870,7 @@
 
   if [[ $state == 'revert_files' ]]
   then
-    if [[ -n $opt_args[-r] ]]
+    if [[ -n ${opt_args[(I)-r|--rev]} ]]
     then
       _hg_files && ret=0
     else