class RSpec::Expectations::MultipleExpectationsNotMetError

def indented(failure_message, index)
  line_1, *rest = failure_message.strip.lines.to_a
  first_line_indentation = ' ' * (longest_index_label_width - width_of_label(index))
  first_line_indentation + line_1 + rest.map do |line|
    line =~ /\S/ ? indentation + line : line
  end.join
end