small fix, don't worry about it

app/backend/internal/networking/service_discovery_test.go

@@ -0,0 +1,38 @@
+package networking
+
+import "testing"
+
+func TestLoadBalancerRoundRobinSelection(t *testing.T) {
+	lb := NewLoadBalancer(StrategyRoundRobin)
+	instances := []*ServiceInstance{
+		{ID: "a"},
+		{ID: "b"},
+	}
+
+	first := lb.SelectInstance(instances, "")
+	second := lb.SelectInstance(instances, "")
+	third := lb.SelectInstance(instances, "")
+
+	if first == nil || second == nil || third == nil {
+		t.Fatalf("expected non-nil selections")
+	}
+	if first.ID != "a" || second.ID != "b" || third.ID != "a" {
+		t.Fatalf("unexpected round-robin order: %s, %s, %s", first.ID, second.ID, third.ID)
+	}
+}
+
+func TestLoadBalancerLeastConnectionsSelection(t *testing.T) {
+	lb := NewLoadBalancer(StrategyLeastConnections)
+	instances := []*ServiceInstance{
+		{ID: "busy", Metadata: map[string]string{"active_connections": "42"}},
+		{ID: "idle", Metadata: map[string]string{"active_connections": "1"}},
+	}
+
+	selected := lb.SelectInstance(instances, "")
+	if selected == nil {
+		t.Fatalf("expected non-nil instance")
+	}
+	if selected.ID != "idle" {
+		t.Fatalf("expected idle instance, got %s", selected.ID)
+	}
+}