@Test
  public void cannotFulfill() throws Throwable {
    when(requirements.canFulfill()).thenReturn(false);

    Runner runner = runnerBuilder.runnerForClass(TestCase.class);

    assertNull(runner);
  }
  @Test
  public void canFulfill() throws Throwable {
    when(requirements.canFulfill()).thenReturn(true);

    Runner runner = runnerBuilder.runnerForClass(TestCase.class);

    assertNotNull(runner);
    assertThat(runner, is(RequirementsRunner.class));
  }