refactor(net): own session wiring subscriptions

tests/AcDream.Core.Net.Tests/WorldSessionWiringOwnershipTests.cs

@@ -0,0 +1,131 @@
+using System.Net;
+using System.Reflection;
+using AcDream.Core.Chat;
+using AcDream.Core.Combat;
+using AcDream.Core.Items;
+using AcDream.Core.Net.Messages;
+using AcDream.Core.Player;
+using AcDream.Core.Spells;
+
+namespace AcDream.Core.Net.Tests;
+
+public sealed class WorldSessionWiringOwnershipTests
+{
+    [Fact]
+    public void ObjectTableWiring_DisposeDetachesEveryExactSessionDelegate()
+    {
+        using var session = NewSession();
+        var table = new ClientObjectTable();
+        var player = new LocalPlayerState();
+
+        IDisposable registration = ObjectTableWiring.Wire(
+            session,
+            table,
+            playerGuid: () => 0x50000001u,
+            localPlayer: player);
+
+        Assert.Equal(1, HandlerCount(session, nameof(session.ObjectIntPropertyUpdated)));
+        Assert.Equal(1, HandlerCount(session, nameof(session.PlayerIntPropertyUpdated)));
+        Assert.Equal(1, HandlerCount(session, nameof(session.PlayerInt64PropertyUpdated)));
+        Assert.Equal(1, HandlerCount(session, nameof(session.StackSizeUpdated)));
+        Assert.Equal(1, HandlerCount(session, nameof(session.InventoryObjectRemoved)));
+
+        registration.Dispose();
+        registration.Dispose();
+
+        Assert.Equal(0, HandlerCount(session, nameof(session.ObjectIntPropertyUpdated)));
+        Assert.Equal(0, HandlerCount(session, nameof(session.PlayerIntPropertyUpdated)));
+        Assert.Equal(0, HandlerCount(session, nameof(session.PlayerInt64PropertyUpdated)));
+        Assert.Equal(0, HandlerCount(session, nameof(session.StackSizeUpdated)));
+        Assert.Equal(0, HandlerCount(session, nameof(session.InventoryObjectRemoved)));
+    }
+
+    [Fact]
+    public void CombatStateWiring_DisposeDetachesOnlyItsExactDelegate()
+    {
+        using var session = NewSession();
+        var combat = new CombatState();
+        Action<WorldSession.PlayerIntPropertyUpdate> predecessor = _ => { };
+        session.PlayerIntPropertyUpdated += predecessor;
+        IDisposable registration = CombatStateWiring.Wire(session, combat);
+
+        Assert.Equal(2, HandlerCount(session, nameof(session.PlayerIntPropertyUpdated)));
+
+        registration.Dispose();
+        registration.Dispose();
+
+        Assert.Equal(1, HandlerCount(session, nameof(session.PlayerIntPropertyUpdated)));
+        session.PlayerIntPropertyUpdated -= predecessor;
+    }
+
+    [Fact]
+    public void CombatStateWiring_ConcurrentDisposeDetachesExactlyOnce()
+    {
+        using var session = NewSession();
+        IDisposable registration = CombatStateWiring.Wire(session, new CombatState());
+
+        Parallel.For(0, 64, _ => registration.Dispose());
+
+        Assert.Equal(0, HandlerCount(session, nameof(session.PlayerIntPropertyUpdated)));
+    }
+
+    [Fact]
+    public void GameEventWiring_DisposeRestoresPreexistingHandlerAndRemovesOwnedSet()
+    {
+        var dispatcher = new GameEventDispatcher();
+        int predecessorCalls = 0;
+        dispatcher.Register(GameEventType.Tell, _ => predecessorCalls++);
+
+        IDisposable registration = GameEventWiring.WireAll(
+            dispatcher,
+            new ClientObjectTable(),
+            new CombatState(),
+            new Spellbook(),
+            new ChatLog());
+        int wiredCount = dispatcher.RegisteredHandlerCount;
+        dispatcher.Dispatch(new GameEventEnvelope(0, 0, GameEventType.Tell, default));
+        Assert.Equal(0, predecessorCalls);
+
+        registration.Dispose();
+        registration.Dispose();
+        dispatcher.Dispatch(new GameEventEnvelope(0, 0, GameEventType.Tell, default));
+
+        Assert.True(wiredCount > 1);
+        Assert.Equal(1, dispatcher.RegisteredHandlerCount);
+        Assert.Equal(1, predecessorCalls);
+    }
+
+    [Fact]
+    public void GameEventWiring_OnWorldSession_RestoresInternalRegistrations()
+    {
+        using var session = NewSession();
+        int baselineCount = session.GameEvents.RegisteredHandlerCount;
+
+        IDisposable registration = GameEventWiring.WireAll(
+            session.GameEvents,
+            new ClientObjectTable(),
+            new CombatState(),
+            new Spellbook(),
+            new ChatLog(),
+            turbineChat: new TurbineChatState());
+
+        Assert.True(session.GameEvents.RegisteredHandlerCount > baselineCount);
+        registration.Dispose();
+
+        Assert.Equal(baselineCount, session.GameEvents.RegisteredHandlerCount);
+    }
+
+    private static WorldSession NewSession() =>
+        new(new IPEndPoint(IPAddress.Loopback, 9));
+
+    private static int HandlerCount(WorldSession session, string eventName)
+    {
+        FieldInfo field = typeof(WorldSession).GetField(
+            eventName,
+            BindingFlags.Instance | BindingFlags.NonPublic)
+            ?? throw new InvalidOperationException($"event field {eventName} not found");
+        return (field.GetValue(session) as MulticastDelegate)?
+            .GetInvocationList()
+            .Length ?? 0;
+    }
+}