* we're copying into a `contents` array whose type allows it to contain nulls. Still, it's
       * worth noting that we promise not to put nulls into the array in the first `size` elements.
       * We uphold that promise here because our callers promise that `elements` will not contain
       * nulls in its first `n` elements.
       */
      System.arraycopy(elements, 0, contents, size, n);
      size += n;

  }

  public void testPowerSetIteration_manual() {
    ImmutableSet<Integer> elements = ImmutableSet.of(1, 2, 3);
    Set<Set<Integer>> powerSet = powerSet(elements);
    // The API doesn't promise this iteration order, but it's convenient here.
    Iterator<Set<Integer>> i = powerSet.iterator();
    assertEquals(ImmutableSet.of(), i.next());
    assertEquals(ImmutableSet.of(1), i.next());

          throw new AssertionFailedError("You weren't supposed to actually invoke me!");
        }
      };

  public void testAnyAndNone_logicalOps() throws Exception {
    // These are testing behavior that's never promised by the API, but since
    // we're lucky enough that these do pass, it saves us from having to write
    // more excruciating tests! Hooray!

    assertSame(CharMatcher.any(), CharMatcher.none().negate());

          throw new AssertionFailedError("You weren't supposed to actually invoke me!");
        }
      };

  public void testAnyAndNone_logicalOps() throws Exception {
    // These are testing behavior that's never promised by the API, but since
    // we're lucky enough that these do pass, it saves us from having to write
    // more excruciating tests! Hooray!

    assertSame(CharMatcher.any(), CharMatcher.none().negate());

    assertSplitterIterableIsLazy(Splitter.on(","));
  }

  @J2ktIncompatible
  @GwtIncompatible // java.util.regex.Pattern
  @AndroidIncompatible // not clear that j.u.r.Matcher promises to handle mutations during use
  public void testSplitterIterableIsLazy_pattern() {
    if (!CommonPattern.isPcreLike()) {
      return;
    }
    assertSplitterIterableIsLazy(Splitter.onPattern(","));
  }

    )
    val url = server.url("/a")
    assertThat(get(url).body.string()).isEqualTo("a")
    val i: Iterator<String> = cache.urls()
    cache.evictAll()

    // The URL was evicted before hasNext() made any promises.
    assertThat(i.hasNext()).isFalse()
    assertFailsWith<NoSuchElementException> {
      i.next()
    }
  }

  /** Test https://github.com/square/okhttp/issues/1712.  */
  @Test