use empty? on the hash to avoid another method call

activesupport/lib/active_support/values/time_zone.rb

@@ -266,7 +266,7 @@ def at(secs)
     #   Time.zone.parse('22:30:00')   # => Fri, 31 Dec 1999 22:30:00 HST -10:00
     def parse(str, now=now)
       date_parts = Date._parse(str)
-      return if date_parts.blank?
+      return if date_parts.empty?
       time = Time.parse(str, now) rescue DateTime.parse(str)
       if date_parts[:offset].nil?
         ActiveSupport::TimeWithZone.new(nil, self, time)