for (int i = 0; i < charsToRead; i++) {
      cbuf[off + i] = seq.charAt(pos++);
    }
    return charsToRead;
  }

  @Override
  public synchronized long skip(long n) throws IOException {
    checkArgument(n >= 0, "n (%s) may not be negative", n);
    checkOpen();
    int charsToSkip = (int) Math.min(remaining(), n); // safe because remaining is an int
    pos += charsToSkip;

    tester.testConstructors(PatternFilenameFilter.class, Visibility.PACKAGE);
    tester.testStaticMethods(PatternFilenameFilter.class, Visibility.PACKAGE); // currently none

    // The reason that we skip this method is discussed in a comment on the method.
    tester.ignore(PatternFilenameFilter.class.getMethod("accept", File.class, String.class));
    tester.testInstanceMethods(new PatternFilenameFilter(".*"), Visibility.PACKAGE);

    assertEquals(bytes.length, source.size());
    assertTrue(source.wasStreamOpened() && source.wasStreamClosed());

    // test that we can get the size even if skip() isn't supported
    assertEquals(bytes.length, new TestByteSource(bytes, SKIP_THROWS).size());

    // test that we can get the size even if available() always returns zero
    assertEquals(bytes.length, new TestByteSource(bytes, AVAILABLE_ALWAYS_ZERO).size());

  @CanIgnoreReturnValue
  public boolean addAll(Collection<? extends E> collection) {
    int size = collection.size();
    if (size >= maxSize) {
      clear();
      return Iterables.addAll(this, Iterables.skip(collection, size - maxSize));
    }
    return standardAddAll(collection);
  }

  @Override
  @J2ktIncompatible // Incompatible return type change. Use inherited implementation
  public Object[] toArray() {

    int result = in.read(b, off, len);
    if (result != -1) {
      count += result;
    }
    return result;
  }

  @Override
  public long skip(long n) throws IOException {
    long result = in.skip(n);
    count += result;
    return result;
  }

  @Override
  public synchronized void mark(int readlimit) {
    in.mark(readlimit);
    mark = count;

   *
   * <p>The default implementation calls {@link #lengthIfKnown} and returns the value if present. If
   * absent, it will fall back to a heavyweight operation that will open a stream, {@link
   * Reader#skip(long) skip} to the end of the stream, and return the total number of chars that
   * were skipped.
   *
   * <p>Note that for sources that implement {@link #lengthIfKnown} to provide a more efficient

              // There are only maxRunBeforeFallback - 1 elements between here and there,
              // so even if they were all nonnull, we wouldn't detect a hash flood.  Therefore,
              // we can skip them all.
              knownRunStart += maxRunBeforeFallback;
            } else {
              knownRunStart++; // the only case in which maxRunEnd doesn't increase by mRBF

    return new QueueTestSuiteBuilder<E>().usingGenerator(generator);
  }

  private boolean runCollectionTests = true;

  /**
   * Specify whether to skip the general collection tests. Call this method when testing a
   * collection that's both a queue and a list, to avoid running the common collection tests twice.
   * By default, collection tests do run.
   */

   *
   * <p>The default implementation calls {@link #sizeIfKnown} and returns the value if present. If
   * absent, it will fall back to a heavyweight operation that will open a stream, read (or {@link
   * InputStream#skip(long) skip}, if possible) to the end of the stream and return the total number
   * of bytes that were read.
   *
   * <p>Note that for some sources that implement {@link #sizeIfKnown} to provide a more efficient

   * @param n the number of characters to skip
   * @throws EOFException if this stream reaches the end before skipping all the characters
   * @throws IOException if an I/O error occurs
   */
  public static void skipFully(Reader reader, long n) throws IOException {
    checkNotNull(reader);
    while (n > 0) {
      long amt = reader.skip(n);
      if (amt == 0) {
        throw new EOFException();