AssertionFailedError failure = new AssertionFailedError(message);
    failure.initCause(cause);
    return failure;
  }

  // This test covers a bug where an Error thrown from a callback could cause the TimeoutFuture to
  // never complete when timing out.  Notably, nothing would get logged since the Error would get

  /**
   * Applies a supplemental hash function to a given hash code, which defends against poor quality
   * hash functions. This is critical when the concurrent hash map uses power-of-two length hash
   * tables, that otherwise encounter collisions for hash codes that do not differ in lower or upper
   * bits.
   *
   * @param h hash code
   */
  static int rehash(int h) {
    // Spread bits to regularize both segment and index locations,

   */
  static int capacity(int expectedSize) {
    if (expectedSize < 3) {
      checkNonnegative(expectedSize, "expectedSize");
      return expectedSize + 1;
    }
    if (expectedSize < Ints.MAX_POWER_OF_TWO) {
      // This seems to be consistent across JDKs. The capacity argument to HashMap and LinkedHashMap
      // ends up being used to compute a "threshold" size, beyond which the internal table

  /**
   * Applies a supplemental hash function to a given hash code, which defends against poor quality
   * hash functions. This is critical when the concurrent hash map uses power-of-two length hash
   * tables, that otherwise encounter collisions for hash codes that do not differ in lower or upper
   * bits.
   *
   * @param h hash code
   */
  static int rehash(int h) {
    // Spread bits to regularize both segment and index locations,

    assertSame(testEquivalence, map.valueEquivalence);
    assertSame(map.keyStrength.defaultEquivalence(), map.keyEquivalence);
  }

  public void testSetConcurrencyLevel() {
    // round up to the nearest power of two

    checkConcurrencyLevel(1, 1);
    checkConcurrencyLevel(2, 2);
    checkConcurrencyLevel(3, 4);
    checkConcurrencyLevel(4, 4);
    checkConcurrencyLevel(5, 8);
    checkConcurrencyLevel(6, 8);

    assertSame(testEquivalence, map.valueEquivalence);
    assertSame(map.keyStrength.defaultEquivalence(), map.keyEquivalence);
  }

  public void testSetConcurrencyLevel() {
    // round up to the nearest power of two

    checkConcurrencyLevel(1, 1);
    checkConcurrencyLevel(2, 2);
    checkConcurrencyLevel(3, 4);
    checkConcurrencyLevel(4, 4);
    checkConcurrencyLevel(5, 8);
    checkConcurrencyLevel(6, 8);

    AssertionFailedError failure = new AssertionFailedError(message);
    failure.initCause(cause);
    return failure;
  }

  // This test covers a bug where an Error thrown from a callback could cause the TimeoutFuture to
  // never complete when timing out.  Notably, nothing would get logged since the Error would get