enable frozen-string-literal option (for Ruby 2.3.0-dev)

1 files changed, 7 insertions, 7 deletions

diff --git a/lib/plum/http_connection.rb b/lib/plum/http_connection.rb
index 61445af..45c6486 100644
--- a/lib/plum/http_connection.rb
+++ b/lib/plum/http_connection.rb
@@ -1,3 +1,4 @@
+# -*- frozen-string-literal: true -*-
 using Plum::BinaryString
 
 module Plum
@@ -6,7 +7,7 @@ module Plum
       require "http/parser"
       super
       @_headers = nil
-      @_body = ""
+      @_body = String.new
       @_http_parser = setup_parser
     end
 
@@ -49,12 +50,11 @@ module Plum
         process_first_request
       }
 
-      resp = ""
-      resp << "HTTP/1.1 101 Switching Protocols\r\n"
-      resp << "Connection: Upgrade\r\n"
-      resp << "Upgrade: h2c\r\n"
-      resp << "Server: plum/#{Plum::VERSION}\r\n"
-      resp << "\r\n"
+      resp = "HTTP/1.1 101 Switching Protocols\r\n"
+             "Connection: Upgrade\r\n"
+             "Upgrade: h2c\r\n"
+             "Server: plum/#{Plum::VERSION}\r\n"
+             "\r\n"
 
       io.write(resp)
     end