For rubocop

lib/facter/icingatest.rb

@@ -16,22 +16,22 @@ if domain == 'vagrant.icinga.org'
 end
 
 if hostname =~ /^icinga-test-(.+)$/
-  fragment = $1
+  fragment = Regexp.last_match(1)
 
   if fragment =~ /^(\w+-\w+)-([a-z]+)(\d+)$/i
     Facter.add(:icingatest_instance) do
       setcode do
-        $1
+        Regexp.last_match(1)
       end
     end
     Facter.add(:icingatest_role) do
       setcode do
-        $2
+        Regexp.last_match(2)
       end
     end
     Facter.add(:icingatest_hostno) do
       setcode do
-        $3
+        Regexp.last_match(3)
       end
     end
   end