public void close() throws IOException {
                super.close();
                counter[0]--;
              }
            };
          }
        };
    Reader joinedReader = CharSource.concat(reader, reader, reader).openStream();
    String result = CharStreams.toString(joinedReader);
    assertEquals(testString.length() * 3, result.length());
  }

  public void testReady() throws Exception {

      Double[] prefix = {Double.MIN_VALUE, Double.MAX_VALUE};
      Double[] suffix = {86.0, 99.0};
      Double[] all = concat(concat(prefix, elements), suffix);
      return asList(all).subList(2, elements.length + 2);
    }
  }

  private static Double[] concat(Double[] left, Double[] right) {
    Double[] result = new Double[left.length + right.length];
    System.arraycopy(left, 0, result, 0, left.length);

      Double[] suffix = {86.0, 99.0};
      Double[] all = concat(concat(prefix, elements), suffix);
      return makeArray(all).subArray(2, elements.length + 2).asList();
    }
  }

  @J2ktIncompatible
  @GwtIncompatible // used only from suite
  @AndroidIncompatible
  private static Double[] concat(Double[] a, Double[] b) {
    return ObjectArrays.concat(a, b, Double.class);
  }

  @J2ktIncompatible

      sources.add(newByteSource(start, span));
      start += span;
    }
    ByteSource joined = ByteSource.concat(sources);
    assertTrue(newByteSource(0, start).contentEquals(joined));
  }

  public void testReadSingleByte() throws Exception {
    ByteSource source = newByteSource(0, 10);
    ByteSource joined = ByteSource.concat(source, source);
    assertEquals(20, joined.size());
    InputStream in = joined.openStream();

          .isTrue();
    }
  }

  public void testCompare() {
    for (byte x : VALUES) {
      for (byte y : VALUES) {
        // Only compare the sign of the result of compare().
        int expected = Byte.compare(x, y);
        int actual = SignedBytes.compare(x, y);
        if (expected == 0) {
          assertWithMessage(x + ", " + y).that(actual).isEqualTo(expected);
        } else if (expected < 0) {

  public void testCompare() {
    // max value
    assertThat(UnsignedLongs.compare(0, 0xffffffffffffffffL)).isLessThan(0);
    assertThat(UnsignedLongs.compare(0xffffffffffffffffL, 0)).isGreaterThan(0);

    // both with high bit set
    assertThat(UnsignedLongs.compare(0xff1a618b7f65ea12L, 0xffffffffffffffffL)).isLessThan(0);
    assertThat(UnsignedLongs.compare(0xffffffffffffffffL, 0xff1a618b7f65ea12L)).isGreaterThan(0);

  ReverseOrdering(Ordering<? super T> forwardOrder) {
    this.forwardOrder = checkNotNull(forwardOrder);
  }

  @Override
  public int compare(@ParametricNullness T a, @ParametricNullness T b) {
    return forwardOrder.compare(b, a);
  }

  @SuppressWarnings("unchecked") // how to explain?
  @Override
  public <S extends T> Ordering<S> reverse() {
    return (Ordering<S>) forwardOrder;
  }

          lowerBound == null || upperBound == null || compare(lowerBound, upperBound) <= 0);
    }

    @Override
    public SortedSet<C> keySet() {
      return new Maps.SortedKeySet<>(this);
    }

    @Override
    public Comparator<? super C> comparator() {
      return columnComparator();
    }

    int compare(Object a, Object b) {
      // pretend we can compare anything
      @SuppressWarnings("unchecked")

    assertThat(Bytes.concat()).isEqualTo(EMPTY);
    assertThat(Bytes.concat(EMPTY)).isEqualTo(EMPTY);
    assertThat(Bytes.concat(EMPTY, EMPTY, EMPTY)).isEqualTo(EMPTY);
    assertThat(Bytes.concat(ARRAY1)).isEqualTo(ARRAY1);
    assertThat(Bytes.concat(ARRAY1)).isNotSameInstanceAs(ARRAY1);
    assertThat(Bytes.concat(EMPTY, ARRAY1, EMPTY)).isEqualTo(ARRAY1);
    assertThat(Bytes.concat(ARRAY1, ARRAY1, ARRAY1))

      buffer[bufferSize++] = elem;
      // uncheckedCastNullableTToT is safe because bufferSize > 0.
      if (comparator.compare(elem, uncheckedCastNullableTToT(threshold)) > 0) {
        threshold = elem;
      }
      // uncheckedCastNullableTToT is safe because bufferSize > 0.
    } else if (comparator.compare(elem, uncheckedCastNullableTToT(threshold)) < 0) {
      // Otherwise, we can ignore elem; we've seen k better elements.