}
  }

  /** A view of a subsection of the containing byte source. */
  private final class SlicedByteSource extends ByteSource {

    final long offset;
    final long length;

    SlicedByteSource(long offset, long length) {
      checkArgument(offset >= 0, "offset (%s) may not be negative", offset);
      checkArgument(length >= 0, "length (%s) may not be negative", length);

   * provided.
   */
  static final class Cell {
    volatile long p0, p1, p2, p3, p4, p5, p6;
    volatile long value;
    volatile long q0, q1, q2, q3, q4, q5, q6;

    Cell(long x) {
      value = x;
    }

    final boolean cas(long cmp, long val) {
      return UNSAFE.compareAndSwapLong(this, valueOffset, cmp, val);
    }

    // Unsafe mechanics

    assertThat(LONG_MANY_VALUES_STATS_ITERATOR.sum())
        .isWithin(ALLOWED_ERROR * LONG_MANY_VALUES_MEAN)
        .of(LONG_MANY_VALUES_MEAN * LONG_MANY_VALUES_COUNT);
    assertThat(LONG_MANY_VALUES_STATS_SNAPSHOT.sum())
        .isWithin(ALLOWED_ERROR * LONG_MANY_VALUES_MEAN)
        .of(LONG_MANY_VALUES_MEAN * LONG_MANY_VALUES_COUNT);
  }

  public void testPopulationVariance() {

        .isNull();
    assertWithMessage("Max long").that(Ints.tryParse(Long.toString(Long.MAX_VALUE))).isNull();
    assertWithMessage("Min long").that(Ints.tryParse(Long.toString(Long.MIN_VALUE))).isNull();
    assertThat(Ints.tryParse("\u0662\u06f3")).isNull();
  }

  /**
   * Applies {@link Ints#tryParse(String)} to the given string and asserts that the result is as
   * expected.

    assertMean(0, 0, 0);
    assertMean(-1, -1, -1);
    assertMean(Long.MIN_VALUE, Long.MIN_VALUE, Long.MIN_VALUE);
    assertMean(Long.MAX_VALUE, Long.MAX_VALUE, Long.MAX_VALUE);

    // Exhaustive checks
    for (long x : ALL_LONG_CANDIDATES) {
      for (long y : ALL_LONG_CANDIDATES) {
        assertMean(x, y);
      }
    }
  }

  /** Helper method that asserts the arithmetic mean of x and y is equal to the expectedMean. */

    testSort(new long[] {2}, 0, 1, new long[] {2});
    testSort(new long[] {2, 1, 0}, 0, 2, new long[] {1, 2, 0});
    testSort(new long[] {2, GREATEST, 1, LEAST}, 1, 4, new long[] {2, LEAST, 1, GREATEST});
  }

  public void testSortDescending() {
    testSortDescending(new long[] {}, new long[] {});
    testSortDescending(new long[] {1}, new long[] {1});
    testSortDescending(new long[] {1, 2}, new long[] {2, 1});

        .isEqualTo(1);
    assertThat(
            Longs.indexOf(
                new long[] {(long) 2, (long) 3, (long) 2, (long) 3, (long) 4, (long) 2, (long) 3},
                new long[] {(long) 2, (long) 3, (long) 4}))
        .isEqualTo(2);
    assertThat(
            Longs.indexOf(
                new long[] {(long) 2, (long) 2, (long) 3, (long) 4, (long) 2, (long) 3, (long) 4},

        .isEqualTo(1);
    assertThat(
            Longs.indexOf(
                new long[] {(long) 2, (long) 3, (long) 2, (long) 3, (long) 4, (long) 2, (long) 3},
                new long[] {(long) 2, (long) 3, (long) 4}))
        .isEqualTo(2);
    assertThat(
            Longs.indexOf(
                new long[] {(long) 2, (long) 2, (long) 3, (long) 4, (long) 2, (long) 3, (long) 4},

   * happens first. Returns the total number of bytes skipped.
   */
  static long skipUpTo(InputStream in, long n) throws IOException {
    long totalSkipped = 0;
    // A buffer is allocated if skipSafely does not skip any bytes.
    byte[] buf = null;

    while (totalSkipped < n) {
      long remaining = n - totalSkipped;
      long skipped = skipSafely(in, remaining);

      if (skipped == 0) {

  public void testCheckedCast() {
    for (long value : UNSIGNED_INTS) {
      assertThat(UnsignedInts.toLong(UnsignedInts.checkedCast(value))).isEqualTo(value);
    }
    assertCastFails(1L << 32);
    assertCastFails(-1L);
    assertCastFails(Long.MAX_VALUE);
    assertCastFails(Long.MIN_VALUE);
  }

  private static void assertCastFails(long value) {
    try {
      UnsignedInts.checkedCast(value);