t.Errorf("first ReadSlice(,) = %q, %v", line, err)
	}
	line, err = buf.ReadSlice('!')
	if string(line) != "world!" || err != nil {
		t.Errorf("second ReadSlice(,) = %q, %v", line, err)
	}
}

func TestPeek(t *testing.T) {
	p := make([]byte, 10)
	// string is 16 (minReadBufferSize) long.
	buf := NewReaderSize(strings.NewReader("abcdefghijklmnop"), minReadBufferSize)
	if s, err := buf.Peek(1); string(s) != "a" || err != nil {