extract repeating code to one method

lib/veewee/provider/virtualbox/box/helper/status.rb

@@ -4,23 +4,25 @@ module Virtualbox
       module BoxCommand
 
         def exists?
-          command="#{@vboxcmd} list vms"
-          shell_results=shell_exec("#{command}",{:mute => true})
-          exists=shell_results.stdout.split(/\n/).grep(/\"#{name.gsub(/\+/,'\\\+')}\"/).size!=0
-
-          env.logger.info("Vm exists? #{exists}")
-          return exists
+          return check?(:exists)
         end
 
         def running?
-          command="#{@vboxcmd} list runningvms"
+          return check?(:running)
+        end
+
+        private
+
+        def check? type
+          command = COMMANDS[type] % @vboxcmd
           shell_results=shell_exec("#{command}",{:mute => true})
-          running=shell_results.stdout.split(/\n/).grep(/\"#{name.gsub(/\+/,'\\\+')}\"/).size!=0
+          status=shell_results.stdout.split(/\n/).grep(/\"#{name.gsub(/\+/,'\\\+')}\"/).size!=0
 
-          env.logger.info("Vm running? #{running}")
-          return running
+          env.logger.info("Vm #{type}? #{status}")
+          return status
         end
 
+        COMMANDS = { :running => "%s list runningvms", :exists => "%s list vms" }
       end
     end
   end