use rspec-puppet-facts for fluentd_install_spec

spec/classes/fluentd_install_spec.rb

@@ -1,8 +1,13 @@
 require 'spec_helper'
 
 describe 'fluentd::install', :type => :class do
+  on_supported_os.each do |os, facts|
+    context "on #{os}" do
+      let :facts do
+        facts
+      end
 
-  shared_examples 'when called with no parameters' do
+      describe 'when called with no parameters' do
         it {
           should contain_package('fluentd').with({
             'ensure'          => 'installed',
@@ -11,28 +16,6 @@ describe 'fluentd::install', :type => :class do
           })
         }
       end
-
-  context 'when osfamily is Debian' do
-    let(:facts) {
-      {
-        :osfamily        => 'Debian',
-        :lsbdistid       => 'Ubuntu',
-        :operatingsystem => 'Ubuntu',
-        :lsbdistcodename => 'precise',
-        :architecture    => 'amd64',
-      }
-    }
-    include_examples 'when called with no parameters'
     end
-
-  context 'when osfamily is RedHat' do
-    let(:facts) {
-      {
-        :osfamily => 'RedHat',
-      }
-    }
-
-    include_examples 'when called with no parameters'
   end
-
 end