fix(commons): resolve Commons-008 — replace ValueTuple in SetConnectionBindingsCommand with named ConnectionBinding record (CLI, ManagementService, TemplateEngine, CentralUI)

tests/ScadaLink.Commons.Tests/Messages/ConnectionBindingSerializationTests.cs

@@ -0,0 +1,54 @@
+using System.Text.Json;
+using ScadaLink.Commons.Messages.Management;
+
+namespace ScadaLink.Commons.Tests.Messages;
+
+/// <summary>
+/// Regression tests for Commons-008 — <see cref="SetConnectionBindingsCommand"/>
+/// previously declared its bindings as <c>IReadOnlyList&lt;(string, int)&gt;</c>.
+/// A <c>ValueTuple</c> serializes as <c>Item1</c>/<c>Item2</c> and cannot evolve
+/// additively (REQ-COM-5a). It is now a named <see cref="ConnectionBinding"/> record.
+/// </summary>
+public class ConnectionBindingSerializationTests
+{
+    [Fact]
+    public void ConnectionBinding_SerializesWithNamedProperties()
+    {
+        var json = JsonSerializer.Serialize(new ConnectionBinding("Temperature", 42));
+
+        using var doc = JsonDocument.Parse(json);
+        Assert.Equal(JsonValueKind.String, doc.RootElement.GetProperty("AttributeName").ValueKind);
+        Assert.Equal("Temperature", doc.RootElement.GetProperty("AttributeName").GetString());
+        Assert.Equal(42, doc.RootElement.GetProperty("DataConnectionId").GetInt32());
+
+        // The ValueTuple failure mode: Item1/Item2 must NOT appear.
+        Assert.False(doc.RootElement.TryGetProperty("Item1", out _));
+        Assert.False(doc.RootElement.TryGetProperty("Item2", out _));
+    }
+
+    [Fact]
+    public void SetConnectionBindingsCommand_RoundTripsThroughJson()
+    {
+        var original = new SetConnectionBindingsCommand(
+            7,
+            new List<ConnectionBinding>
+            {
+                new("Speed", 5),
+                new("Mode", 11),
+            });
+
+        var json = JsonSerializer.Serialize(original);
+        var deserialized = JsonSerializer.Deserialize<SetConnectionBindingsCommand>(json);
+
+        Assert.NotNull(deserialized);
+        Assert.Equal(7, deserialized!.InstanceId);
+        Assert.Equal(2, deserialized.Bindings.Count);
+        Assert.Equal("Speed", deserialized.Bindings[0].AttributeName);
+        Assert.Equal(5, deserialized.Bindings[0].DataConnectionId);
+        Assert.Equal("Mode", deserialized.Bindings[1].AttributeName);
+        Assert.Equal(11, deserialized.Bindings[1].DataConnectionId);
+
+        // ConnectionBinding is a record: each element compares by value.
+        Assert.Equal(original.Bindings, deserialized.Bindings);
+    }
+}