helper_test.html.erb

      <%@user.dob = Time.now %>

      <h2>default state of datetime_select and select_datetime</h2>
      <%= f.datetime_select :dob %><br />
      <%= select_datetime Time.now %>

      <h2>discard_hour => true</h2>
      <%= f.datetime_select :dob, :discard_hour => true %><br />
      <%= select_datetime Time.now, :discard_hour => true %>

      <h2>discard_month => true</h2>
      <%= f.datetime_select :dob, :discard_month => true %><br />
      <%= select_datetime Time.now, :discard_month => true %>

      <h2>ignore_date => true</h2>
      <%= f.datetime_select :dob, :ignore_date => true %><br />
      <%= select_datetime Time.now, :ignore_date => true %>