t.Fatalf("expect 16 abcd and 4 1234 but got %s. r.w=%d, r.r=%d", rb.Bytes(nil), rb.w, rb.r)
	}
}

func TestRingBuffer_WriteBlocking(t *testing.T) {
	rb := New(64).SetBlocking(true)

	// check empty or full
	if !rb.IsEmpty() {
		t.Fatalf("expect IsEmpty is true but got false")
	}
	if rb.IsFull() {
		t.Fatalf("expect IsFull is false but got true")
	}
	if rb.Length() != 0 {

		size: size,
	}
}

// NewBuffer returns a new RingBuffer whose buffer is provided.
func NewBuffer(b []byte) *RingBuffer {
	return &RingBuffer{
		buf:  b,
		size: len(b),
	}
}

// SetBlocking sets the blocking mode of the ring buffer.
// If block is true, Read and Write will block when there is no data to read or no space to write.
// If block is false, Read and Write will return ErrIsEmpty or ErrIsFull immediately.

			rb.Read(buf)
		}
	}()

	for b.Loop() {
		rb.Write(data)
	}
}

func BenchmarkRingBuffer_AsyncReadBlocking(b *testing.B) {
	const sz = 512
	const buffers = 10
	rb := New(sz * buffers)
	rb.SetBlocking(true)
	data := []byte(strings.Repeat("a", sz))
	buf := make([]byte, sz)

	go func() {
		for {
			rb.Read(buf)
		}
	}()

	for b.Loop() {
		rb.Write(data)
	}
}