# File lib/rack/mock.rb, line 145
145:     def initialize(status, headers, body, errors=StringIO.new(""))
146:       @status = status.to_i
147: 
148:       @original_headers = headers
149:       @headers = Rack::Utils::HeaderHash.new
150:       headers.each { |field, values|
151:         @headers[field] = values
152:         @headers[field] = ""  if values.empty?
153:       }
154: 
155:       @body = ""
156:       body.each { |part| @body << part }
157: 
158:       @errors = errors.string if errors.respond_to?(:string)
159:     end