}

func TestNoUnreadRuneAfterPeek(t *testing.T) {
	br := NewReader(strings.NewReader("example"))
	br.ReadRune()
	br.Peek(1)
	if err := br.UnreadRune(); err == nil {
		t.Error("UnreadRune didn't fail after Peek")
	}
}

func TestNoUnreadByteAfterPeek(t *testing.T) {
	br := NewReader(strings.NewReader("example"))
	br.ReadByte()
	br.Peek(1)
	if err := br.UnreadByte(); err == nil {

	BC 20,undefined_symbol,LR       // BC $20,CR0LT,LR // 4e800020
	BC 20,undefined_symbol+1,LR     // BC $20,CR0GT,LR // 4e810020
	JMP LR                          // 4e800020
	BR LR                           // JMP LR // 4e800020
	BCL $20,CR0LT,$1,LR             // 4e800821
	BCL $20,CR0LT,$0,LR             // 4e800021
	BCL $20,CR0LT,LR                // 4e800021