    @Test
    public void oldTimestampMustCauseTrialToBeOver() {

        Context context = mock(Context.class);
        TrialFactor factor = mock(TrialFactor.class);
        when(factor.readTimestamp(any(Context.class))).thenReturn(123L);

        SimpleTrial trial = new SimpleTrial(context, new SimpleTrial.Config().factors(factor));

        verify(factor).persistTimestamp(123L, context);
        assertTrue(trial.isTrialPeriodFinished());
    }