in, _ := os.Open("../resources/demo.flac")
		defer in.Close()

		buff := bytes.NewBuffer(make([]byte, 0, MB))
		//read by parttition
		for i := 0; i < 1000; i++ {
			buff.Reset()
			length, err := buff.ReadFrom(io.LimitReader(in, MB))
			if nil != err && !errors.Is(err, io.EOF) {
				t.FailNow()
			} else if errors.Is(err, io.EOF) {
                               // this does not happen
				break
			}
			t.Logf("read:%d\n", length)
		}

// ReadFrom reads data from r until EOF and appends it to the buffer, growing
// the buffer as needed. The return value n is the number of bytes read. Any
// error except io.EOF encountered during the read is also returned. If the
// buffer becomes too large, ReadFrom will panic with [ErrTooLarge].
func (b *Buffer) ReadFrom(r io.Reader) (n int64, err error) {
	b.lastRead = opInvalid
	for {
		i := b.grow(MinRead)
		b.buf = b.buf[:i]
		m, e := r.Read(b.buf[i:cap(b.buf)])
		if m < 0 {
			panic(errNegativeRead)
		}

		b.buf = b.buf[:i+m]
		n += int64(m)
		if e == io.EOF {
			return n, nil // e is EOF, so return nil explicitly
		}
		if e != nil {
			return n, e
		}
	}
}