diff --git a/spec/guard/notifier_spec.rb b/spec/guard/notifier_spec.rb
index 652d9ef..900684d 100644
--- a/spec/guard/notifier_spec.rb
+++ b/spec/guard/notifier_spec.rb
@@ -35,16 +35,14 @@ describe Guard::Notifier do
     describe ".turn_off" do
       before(:each) { subject.turn_off }
 
-      if mac?
-        require 'growl'
+      if mac? && Guard::Notifier.growl_installed?
         it "does nothing" do
           Growl.should_not_receive(:notify)
           subject.notify 'great', :title => 'Guard'
         end
       end
 
-      if linux?
-        require 'libnotify'
+      if linux? && Guard::Notifier.libnotify_installed?
         it "does nothing" do
           Libnotify.should_not_receive(:show)
           subject.notify 'great', :title => 'Guard'