assertFalse(map.containsKey(keyOne));
        assertFalse(map.containsValue(valueOne));
        assertThat(map.get(keyOne)).isNull();
        assertEquals(1, map.size());
        assertThat(segment.getValueReferenceQueueForTesting().poll()).isNull();
      }
    }
  }

  public void testDrainKeyReferenceQueueOnRead() {
    for (MapMaker maker : allWeakKeyStrengthMakers()) {

        assertFalse(map.containsKey(keyOne));
        assertFalse(map.containsValue(valueOne));
        assertThat(map.get(keyOne)).isNull();
        assertEquals(1, map.size());
        assertThat(segment.getValueReferenceQueueForTesting().poll()).isNull();
      }
    }
  }

  public void testDrainKeyReferenceQueueOnRead() {
    for (MapMaker maker : allWeakKeyStrengthMakers()) {

    ReferenceQueue<K> getKeyReferenceQueueForTesting() {
      throw new AssertionError();
    }

    /** Unsafely extracts the value reference queue used by this segment. */
    ReferenceQueue<V> getValueReferenceQueueForTesting() {
      throw new AssertionError();
    }

    /** Unsafely extracts the weak value reference inside of the given {@code entry}. */