class RSpec::Matchers::BuiltIn::ChangeFromValue

def does_not_match?(event_proc)

Other tags:
    Private: -
def does_not_match?(event_proc)
  if @description_suffix
    raise NotImplementedError, "`expect { }.not_to change { }.to()` " \
      "is not supported"
  end
  perform_change(event_proc) && !@change_details.changed? && @matches_before
end