assertEquals(23, stats.totalLoadTime());
    assertThat(stats.averageLoadPenalty()).isEqualTo(23.0 / (17 + 19));
    assertEquals(27, stats.evictionCount());
  }

  public void testMinus() {
    CacheStats one = new CacheStats(11, 13, 17, 19, 23, 27);
    CacheStats two = new CacheStats(53, 47, 43, 41, 37, 31);

    CacheStats diff = two.minus(one);
    assertEquals(76, diff.requestCount());

    while ((read = reader.read(buf)) != -1) {
      writer.write(buf, 0, read);
    }
    reader.close();
    writer.close();

    assertExpectedString(writer.toString());
  }

  public void testLines() throws IOException {
    try (Stream<String> lines = source.lines()) {
      assertExpectedLines(lines.collect(toImmutableList()));
    }
  }

  public void testCopyTo_appendable() throws IOException {