class Rack::Head

all other requests unchanged.
Rack::Head returns an empty body for all HEAD requests. It leaves

def call(env) 

def call(env)
  _, _, body = response = @app.call(env)
  if env[REQUEST_METHOD] == HEAD
    response[2] = Rack::BodyProxy.new([]) do
      body.close if body.respond_to? :close
    end
  end
  response
end

def initialize(app) 

def initialize(app)
  @app = app
end