class Shoulda::Matchers::ActionController::SetSessionOrFlashMatcher

def expectation_description
  String.new('set').tap do |string|
    string <<
      if key_set?
        " #{store.name}[#{key.inspect}]"
      else
        " any key in #{store.name}"
      end
    if expected_value_set?
      string <<
        if expected_value.is_a?(Regexp)
          " to a value matching #{expected_value.inspect}"
        else
          " to #{expected_value.inspect}"
        end
    end
  end
end