fix: return directly if no futures

api.go

@@ -105,6 +105,10 @@ func ToAny[T any](f *Future[T]) *Future[any] {
 }
 
 func AllOf[T any](fs ...*Future[T]) *Future[struct{}] {
+	if len(fs) == 0 {
+		return Done(struct{}{})
+	}
+
 	var done uint32
 	s := &state[struct{}]{}
 	c := int32(len(fs))

api_test.go

@@ -331,6 +331,14 @@ func TestAllOf(t *testing.T) {
 	}
 }
 
+func TestAllOfEmpty(t *testing.T) {
+	fs := make([]*Future[int], 0)
+	f := AllOf(fs...)
+	r, err := f.Get()
+	assert.Equal(t, struct{}{}, r)
+	assert.NoError(t, err)
+}
+
 func TestAllOfWhenErr(t *testing.T) {
 	target := rand.Intn(10)
 	vals := make([]int, 10)