Merge pull request #8366 from justinsb/idempotent_loadbalancer

Make LoadBalancer creation more self-healing; don't delete on AWS

pkg/util/set.go

@@ -131,6 +131,21 @@ func (s1 StringSet) IsSuperset(s2 StringSet) bool {
 	return true
 }
 
+// Equal returns true iff s1 is equal (as a set) to s2.
+// Two sets are equal if their membership is identical.
+// (In practice, this means same elements, order doesn't matter)
+func (s1 StringSet) Equal(s2 StringSet) bool {
+	if len(s1) != len(s2) {
+		return false
+	}
+	for item := range s2 {
+		if !s1.Has(item) {
+			return false
+		}
+	}
+	return true
+}
+
 // List returns the contents as a sorted string slice.
 func (s StringSet) List() []string {
 	res := make([]string, 0, len(s))

pkg/util/set_test.go

@@ -129,3 +129,57 @@ func TestStringSetHasAny(t *testing.T) {
 		t.Errorf("expected false, got true")
 	}
 }
+
+func TestStringSetEquals(t *testing.T) {
+	// Simple case (order doesn't matter)
+	a := NewStringSet("1", "2")
+	b := NewStringSet("2", "1")
+	if !a.Equal(b) {
+		t.Errorf("Expected to be equal: %v vs %v", a, b)
+	}
+
+	// It is a set; duplicates are ignored
+	b = NewStringSet("2", "2", "1")
+	if !a.Equal(b) {
+		t.Errorf("Expected to be equal: %v vs %v", a, b)
+	}
+
+	// Edge cases around empty sets / empty strings
+	a = NewStringSet()
+	b = NewStringSet()
+	if !a.Equal(b) {
+		t.Errorf("Expected to be equal: %v vs %v", a, b)
+	}
+
+	b = NewStringSet("1", "2", "3")
+	if a.Equal(b) {
+		t.Errorf("Expected to be not-equal: %v vs %v", a, b)
+	}
+
+	b = NewStringSet("1", "2", "")
+	if a.Equal(b) {
+		t.Errorf("Expected to be not-equal: %v vs %v", a, b)
+	}
+
+	// Check for equality after mutation
+	a = NewStringSet()
+	a.Insert("1")
+	if a.Equal(b) {
+		t.Errorf("Expected to be not-equal: %v vs %v", a, b)
+	}
+
+	a.Insert("2")
+	if a.Equal(b) {
+		t.Errorf("Expected to be not-equal: %v vs %v", a, b)
+	}
+
+	a.Insert("")
+	if !a.Equal(b) {
+		t.Errorf("Expected to be equal: %v vs %v", a, b)
+	}
+
+	a.Delete("")
+	if a.Equal(b) {
+		t.Errorf("Expected to be not-equal: %v vs %v", a, b)
+	}
+}