call

# File actionpack/lib/action_dispatch/middleware/head.rb, line 7
    def call(env)
      if env["REQUEST_METHOD"] == "HEAD"
        env["REQUEST_METHOD"] = "GET"
        env["rack.methodoverride.original_method"] = "HEAD"
        status, headers, _ = @app.call(env)
        [status, headers, []]
      else
        @app.call(env)
      end
    end