messagemapper: fix set_auth_path() logic

diff --git a/lib/rbot/messagemapper.rb b/lib/rbot/messagemapper.rb
index 8b52baa4a04392ee4c5d8ab78070b644e46ee39f..62543f327bbadc60b57acdcc34bc7614fcd43ddd 100644 (file)
--- a/lib/rbot/messagemapper.rb
+++ b/lib/rbot/messagemapper.rb
@@ -413,6 +413,7 @@ class Bot
           end
           pre = nil if extra.sub!(/^!/, "")
           post = nil if extra.sub!(/!$/, "")
+          extra = nil if extra.empty?
         else
           extra = nil
         end