byte[] copy = bytes.clone();
    copy[9876] = 1;
    ByteSource oneByteOff = new TestByteSource(copy);
    assertFalse(source.contentEquals(oneByteOff));
  }

  public void testSlice() throws IOException {
    // Test preconditions
    assertThrows(IllegalArgumentException.class, () -> source.slice(-1, 10));

    assertThrows(IllegalArgumentException.class, () -> source.slice(0, -1));

    byte[] copy = bytes.clone();
    copy[9876] = 1;
    ByteSource oneByteOff = new TestByteSource(copy);
    assertFalse(source.contentEquals(oneByteOff));
  }

  public void testSlice() throws IOException {
    // Test preconditions
    assertThrows(IllegalArgumentException.class, () -> source.slice(-1, 10));

    assertThrows(IllegalArgumentException.class, () -> source.slice(0, -1));

  }

  public void testSize0() {
    Iterator<String> iterator = emptyIterator();
    assertEquals(0, Iterators.size(iterator));
  }

  public void testSize1() {
    Iterator<Integer> iterator = singleton(0).iterator();
    assertEquals(1, Iterators.size(iterator));
  }

  public void testSize_partiallyConsumed() {

  }

  public void testSize0() {
    Iterator<String> iterator = emptyIterator();
    assertEquals(0, Iterators.size(iterator));
  }

  public void testSize1() {
    Iterator<Integer> iterator = singleton(0).iterator();
    assertEquals(1, Iterators.size(iterator));
  }

  public void testSize_partiallyConsumed() {