@Test
public void normalizesToPositiveReadings() {

    expect(mockEnv.nanoTime()).andReturn(-100L);
    expect(mockEnv.nanoTime()).andReturn(-90L).anyTimes();
    expect(mockEnv.currentTimeMillis()).andReturn(0L).anyTimes();
    replay(mockEnv);
    DiscreteInterval out = impl.getNanoTime();
    verify(mockEnv);
    assertTrue(out.getMin() >= 0);
    assertTrue(out.getMax() >= 0);
}