lib/packetgen/header/tcp.rb in packetgen-3.1.3 vs lib/packetgen/header/tcp.rb in packetgen-3.1.4

@@ -1,12 +1,12 @@
+# frozen_string_literal: true
+
 # This file is part of PacketGen
 # See https://github.com/sdaubert/packetgen for more informations
 # Copyright (C) 2016 Sylvain Daubert <[e-mail]>
 # This program is published under MIT license.
 
-# frozen_string_literal: true
-
 module PacketGen
   module Header
     # TCP header ({https://tools.ietf.org/html/rfc793 RFC 793})
     #    0                   1                   2                   3
     #    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
@@ -233,10 +233,10 @@
           shift = Inspect.shift_level
           str = Inspect.inspect_attribute(attr, self[attr])
           doff = Inspect.int_dec_hex(data_offset, 1)
           str << shift << Inspect::FMT_ATTR % ['', 'data_offset', doff]
           str << shift << Inspect::FMT_ATTR % ['', 'reserved', reserved]
-          flags = ''.dup
+          flags = +''
           %w[ns cwr ece urg ack psh rst syn fin].each do |fl|
             flags << (send("flag_#{fl}?") ? fl[0].upcase : '.')
           end
           str << shift << Inspect::FMT_ATTR % ['', 'flags', flags]
         end