}{
		{
			name:         "normal case",
			r:            strings.NewReader("abcdefghijklmnopqrstuvwxyz"),
			peekSize:     16,
			n:            6,
			want:         6,
			wantBuffered: 10,
		},
		{
			name:         "discard causing read",
			r:            strings.NewReader("abcdefghijklmnopqrstuvwxyz"),
			n:            6,
			want:         6,
			wantBuffered: 10,
		},
		{

		t.Fatal("ReadByte at EOF: got no error")
	}
	if err := b.UnreadByte(); err == nil {
		t.Fatal("UnreadByte after ReadByte at EOF: got no error")
	}

	// check not at EOF
	b.WriteString("abcdefghijklmnopqrstuvwxyz")

	// after unsuccessful read
	if n, err := b.Read(nil); n != 0 || err != nil {
		t.Fatalf("Read(nil) = %d,%v; want 0,nil", n, err)
	}
	if err := b.UnreadByte(); err == nil {

			panic("didn't get enough data")
		}
		if numSplits >= okCount {
			return 0, nil, testError
		}
		numSplits++
		return 1, data[0:1], nil
	}
	// Read the data.
	const text = "abcdefghijklmnopqrstuvwxyz"
	buf := strings.NewReader(text)
	s := NewScanner(&slowReader{1, buf})
	s.Split(errorSplit)
	var i int
	for i = 0; s.Scan(); i++ {
		if len(s.Bytes()) != 1 || text[i] != s.Bytes()[0] {