}
}

type dataAndEOFReader string

func (r dataAndEOFReader) Read(p []byte) (int, error) {
	return copy(p, r), io.EOF
}

func TestPeekThenUnreadRune(t *testing.T) {
	// This sequence used to cause a crash.
	r := NewReader(strings.NewReader("x"))
	r.ReadRune()
	r.Peek(1)
	r.UnreadRune()
	r.ReadRune() // Used to panic here
}