h2 := new(Hash)
	h2.SetSeed(h1.Seed())
	h2.WriteString("foo")
	y := h2.Sum64()
	if x != y {
		t.Errorf("hashes don't match: want %x, got %x", x, y)
	}
}

func TestSeedFromSeed(t *testing.T) {
	h1 := new(Hash)
	h1.WriteString("foo")
	_ = h1.Seed() // seed generated here
	x := h1.Sum64()
	h2 := new(Hash)
	h2.SetSeed(h1.Seed())
	h2.WriteString("foo")
	y := h2.Sum64()