func TestIntersectionWith(t *testing.T) {
// Edge cases: the pairs (1,1), (1000,2000), (8000,4000)
// exercise the <, >, == cases in IntersectionWith that the
// TestSetOperations data is too dense to cover.
var X, Y intsets.Sparse
X.Insert(1)
X.Insert(1000)
X.Insert(8000)
Y.Insert(1)
Y.Insert(2000)
Y.Insert(4000)
X.IntersectionWith(&Y)
if got, want := X.String(), "{1}"; got != want {
t.Errorf("IntersectionWith: got %s, want %s", got, want)
}
}
func TestIntersects(t *testing.T) {
prng := rand.New(rand.NewSource(0))
for i := uint(0); i < 12; i++ {
X, Y := randomPset(prng, 1<<i), randomPset(prng, 1<<i)
x, y := &X.bits, &Y.bits
// test the slow way
var z intsets.Sparse
z.Copy(x)
z.IntersectionWith(y)
if got, want := x.Intersects(y), !z.IsEmpty(); got != want {
t.Errorf("Intersects: got %v, want %v", got, want)
}
// make it false
a := x.AppendTo(nil)
for _, v := range a {
y.Remove(v)
}
if got, want := x.Intersects(y), false; got != want {
t.Errorf("Intersects: got %v, want %v", got, want)
}
// make it true
if x.IsEmpty() {
continue
}
i := prng.Intn(len(a))
y.Insert(a[i])
if got, want := x.Intersects(y), true; got != want {
t.Errorf("Intersects: got %v, want %v", got, want)
}
}
}