instance method encode_json

# File activesupport/lib/active_support/json/encoding.rb, line 248
  def encode_json(encoder)
    # values are encoded with use_options = false, because we don't want hash representations from ActiveModel to be
    # processed once again with as_json with options, as this could cause unexpected results (i.e. missing fields);

    # on the other hand, we need to run as_json on the elements, because the model representation may contain fields
    # like Time/Date in their original (not jsonified) form, etc.

    "{#{map { |k,v| "#{encoder.encode(k.to_s)}:#{encoder.encode(v, false)}" } * ','}}"
  end