if g, w := err, io.EOF; g != w {
		t.Errorf("Error mismatch\n\tGot:  %v\n\tWant: %v", g, w)
	}
	if g, w := n, 0; g != w {
		t.Errorf("Unexpectedly read %d bytes, wanted %d", g, w)
	}
}

func TestHalfReader_nonEmptyReader(t *testing.T) {
	msg := "Hello, World!"
	buf := new(bytes.Buffer)
	buf.WriteString(msg)
	// empty read buffer
	hr := HalfReader(buf)
	var b []byte
	n, err := hr.Read(b)
	if err != nil || n != 0 {