Merge branch '1.3-stable'

Author: chadlwilson

src/main/java/org/jruby/rack/ext/Response.java

@@ -369,6 +369,10 @@ protected void writeHeaders(final RackResponseEnvironment response) {
             public void visit(final IRubyObject key, final IRubyObject val) {
                 final String name = key.toString();
 
+                // SPEC: special headers starting "rack." are for communicating
+                // with the server and must not be sent back to the client
+                if ( name.startsWith("rack.") ) return;
+
                 if ( name.equalsIgnoreCase("Content-Type") ) {
                     response.setContentType( val.asJavaString() ); return;
                 }

src/spec/ruby/jruby/rack/response_spec.rb

@@ -112,6 +112,14 @@ class << value
     response.to_java.respond(response_environment)
   end
 
+  it "does not send rack. headers to the client" do
+    headers = { "rack.hijack" => Object.new, "Server" => "Trinidad" }
+    response = JRuby::Rack::Response.new [200, headers, ['body']]
+    expect(servlet_response).to receive(:addHeader).with("Server", "Trinidad")
+    expect(servlet_response).not_to receive(:addHeader).with("rack.hijack", anything)
+    response.write_headers(response_environment)
+  end
+
   it "calls close on the body if the body responds to close" do
     body = double('body')
     expect(body).to receive(:each).ordered.and_yield "hello"