rerere: don't segfault on failure to open rr-cache

diff --git a/git-mergetool--lib.sh b/git-mergetool--lib.sh
index bfb01f7842e6192e0b3fbc0e3f2ab96269578289..334af7c3478bd6e4fa3f29e360b6be4fbaf6f8cb 100644 (file)
--- a/git-mergetool--lib.sh
+++ b/git-mergetool--lib.sh
@@ -325,15 +325,14 @@ guess_merge_tool () {
                fi
                tools="$tools gvimdiff diffuse ecmerge araxis"
        fi
-       if echo "${VISUAL:-$EDITOR}" | grep emacs > /dev/null 2>&1; then
-               # $EDITOR is emacs so add emerge as a candidate
-               tools="$tools emerge vimdiff"
-       elif echo "${VISUAL:-$EDITOR}" | grep vim > /dev/null 2>&1; then
-               # $EDITOR is vim so add vimdiff as a candidate
+       case "${VISUAL:-$EDITOR}" in
+       *vim*)
                tools="$tools vimdiff emerge"
-       else
+               ;;
+       *)
                tools="$tools emerge vimdiff"
-       fi
+               ;;
+       esac
        echo >&2 "merge tool candidates: $tools"
 
        # Loop over each candidate and stop when a valid merge tool is found.