diff --git a/on_what.rb b/on_what.rb
index b1ffa28..8d672d4 100644
--- a/on_what.rb
+++ b/on_what.rb
@@ -6,9 +6,9 @@ def on_travis?
 end
 
 def on_jruby?
-  (defined?(RUBY_ENGINE) && 'jruby' == RUBY_ENGINE)
+  defined?(RUBY_ENGINE) && 'jruby' == RUBY_ENGINE
 end
 
 def on_1_8?
   RUBY_VERSION.start_with? '1.8'
-end
\ No newline at end of file
+end