assertEquals(
        "Modifying the builder should not have changed any already" + " built sets",
        216,
        webSafeColors.size());
    assertEquals("the new array should be one bigger than webSafeColors", 217, addedColor.size());
    Integer[] appendColorArray = addedColor.toArray(new Integer[addedColor.size()]);
    assertEquals(0x00BFFF, (int) appendColorArray[216]);
  }

              || !fitsInLong(BigIntegerMath.binomial(LongMath.biggestBinomials[k] + 1, k)));
      // In the first case, any long is valid; in the second, we want to test that the next-bigger
      // long overflows.
    }
    int k = LongMath.biggestBinomials.length;
    assertFalse(fitsInLong(BigIntegerMath.binomial(2 * k, k)));
    // 2 * k is the smallest value for which we don't replace k with (n-k).

   *
   * @param file the file to read from
   * @return a byte array containing all the bytes from file
   * @throws IllegalArgumentException if the file is bigger than the largest possible byte array
   *     (2^31 - 1)
   * @throws IOException if an I/O error occurs
   */
  public static byte[] toByteArray(File file) throws IOException {
    return asByteSource(file).read();