Prevents double headers from going out.

git-svn-id: svn+ssh://rubyforge.org/var/svn/mongrel/trunk@415 19e92222-5c0b-0410-8929-a290d50e31e9

lib/mongrel.rb

@@ -322,12 +322,16 @@ module Mongrel
     attr_reader :out
 
     def initialize(out)
+      @sent = {}
       @out = out
     end
 
     # Simply writes "#{key}: #{value}" to an output buffer.
     def[]=(key,value)
-      @out.write(Const::HEADER_FORMAT % [key, value])
+      if not @sent.has_key?(key)
+        @sent[key] = true
+        @out.write(Const::HEADER_FORMAT % [key, value])
+      end
     end
   end
 

test/test_response.rb

@@ -37,6 +37,19 @@ class ResponseTest < Test::Unit::TestCase
     assert io.length > 0, "output didn't have data"
   end
 
+  def test_response_duplicate_header_squash
+    io = StringIO.new
+    resp = HttpResponse.new(io)
+    resp.start do |head,out|
+      head["Content-Length"] = 30
+      head["Content-Length"] = 0
+    end
+
+    resp.finished
+
+    assert_equal io.length, 95, "too much output"
+  end
+
   def test_response_404
     io = StringIO.new