# 单元测试 01 · SO 事件系统 & ServiceLocator

> **测试类型**：EditMode 单元测试（NUnit）  
> **测试文件**：`Assets/Tests/EditMode/EventSystemTests.cs`  
> **被测程序集**：`BaseGames.Core.Events`  
> **asmdef 依赖配置**：`BaseGames.Tests.EditMode.asmdef` 需引用 `BaseGames.Core.Events`

---

## 目录

1. [测试覆盖范围](#1-测试覆盖范围)
2. [EventSubscription & CompositeDisposable 测试](#2-eventsubscription--compositedisposable-测试)
3. [BaseEventChannelSO 测试](#3-baseeventchannelso-测试)
4. [ServiceLocator 测试](#4-servicelocator-测试)
5. [完整测试代码](#5-完整测试代码)

---

## 1. 测试覆盖范围

| 类 | 测试点 |
|----|--------|
| `EventSubscription` | Dispose 后自动取消回调 |
| `CompositeDisposable` | Clear/Dispose 批量取消；Add 后 Clear 清空 |
| `EventSubscriptionExtensions.AddTo` | 返回原订阅句柄（链式调用不丢失引用） |
| `BaseEventChannelSO<T>` | Raise 触发所有订阅者；订阅者为 0 时 Raise 不抛异常 |
| `VoidBaseEventChannelSO` | 同上（无负载版） |
| `ServiceLocator` | Register/Get/Unregister；未注册时 Get 抛异常；RegisterIfAbsent 防重复 |

---

## 2. EventSubscription & CompositeDisposable 测试

### 测试说明

`EventSubscription` 是纯 C# struct，完全无 Unity 依赖，适合 EditMode 测试。

**关键验证点：**

- `Dispose()` 调用 unsubscribe Action
- `CompositeDisposable.Clear()` 遍历调用所有子项的 `Dispose()`
- `AddTo()` 扩展方法正确将订阅加入 CompositeDisposable

---

## 3. BaseEventChannelSO 测试

### 测试说明

`BaseEventChannelSO<T>` 继承 `ScriptableObject`，在 EditMode 中需要用 `ScriptableObject.CreateInstance<T>()` 创建实例（不能 `new`）。

**创建方式：**

```csharp
var channel = ScriptableObject.CreateInstance<IntEventChannelSO>();
```

> ⚠️ 测试结束后必须调用 `Object.DestroyImmediate(channel)` 防止内存泄漏。

---

## 4. ServiceLocator 测试

### 测试说明

`ServiceLocator` 是静态类，测试间有状态污染风险。每个测试前必须调用 `ServiceLocator.Reset()` 清空状态（已在 `#if UNITY_EDITOR` 块内提供）。

**关键验证点：**

- `Register<T>` 后 `Get<T>()` 返回正确实例
- `Get<T>()` 未注册时抛出 `InvalidOperationException`
- `GetOrDefault<T>()` 未注册时返回 `default` 不抛异常
- `RegisterIfAbsent<T>()` 重复注册时不覆盖
- `Unregister<T>(impl)` 只在实例匹配时才移除

---

## 5. 完整测试代码

将以下代码保存至 `Assets/Tests/EditMode/EventSystemTests.cs`：

```csharp
using System;
using System.Collections.Generic;
using NUnit.Framework;
using UnityEngine;
using BaseGames.Core.Events;
using BaseGames.Core;

namespace BaseGames.Tests.EditMode
{
    /// <summary>
    /// SO 事件系统 + ServiceLocator 单元测试（EditMode，无需 Play Mode）。
    /// </summary>
    [TestFixture]
    public class EventSystemTests
    {
        // ── EventSubscription ────────────────────────────────────────────────

        [Test]
        public void EventSubscription_Dispose_CallsUnsubscribeAction()
        {
            bool called = false;
            var sub = new EventSubscription(() => called = true);
            sub.Dispose();
            Assert.IsTrue(called, "Dispose 应调用 unsubscribe action");
        }

        [Test]
        public void EventSubscription_Dispose_NullAction_DoesNotThrow()
        {
            var sub = new EventSubscription(null);
            Assert.DoesNotThrow(() => sub.Dispose());
        }

        // ── CompositeDisposable ──────────────────────────────────────────────

        [Test]
        public void CompositeDisposable_Clear_DisposesAllItems()
        {
            var composite = new CompositeDisposable();
            int count = 0;
            composite.Add(new EventSubscription(() => count++));
            composite.Add(new EventSubscription(() => count++));
            composite.Add(new EventSubscription(() => count++));

            composite.Clear();
            Assert.AreEqual(3, count, "Clear 应 Dispose 所有已添加的订阅");
        }

        [Test]
        public void CompositeDisposable_Clear_TwiceSafe()
        {
            var composite = new CompositeDisposable();
            int count = 0;
            composite.Add(new EventSubscription(() => count++));
            composite.Clear();
            composite.Clear(); // 第二次 Clear 不应重复 Dispose
            Assert.AreEqual(1, count, "Clear 两次不应重复 Dispose");
        }

        [Test]
        public void CompositeDisposable_Dispose_SameAsClear()
        {
            var composite = new CompositeDisposable();
            bool disposed = false;
            composite.Add(new EventSubscription(() => disposed = true));
            ((IDisposable)composite).Dispose();
            Assert.IsTrue(disposed);
        }

        [Test]
        public void AddTo_ReturnsOriginalSubscription()
        {
            var composite = new CompositeDisposable();
            bool called = false;
            var sub = new EventSubscription(() => called = true);
            var returned = sub.AddTo(composite);
            returned.Dispose();
            Assert.IsTrue(called, "AddTo 返回的订阅 Dispose 后应触发原 unsubscribe");
        }

        [Test]
        public void AddTo_Collection_AddsToList()
        {
            var list = new List<IDisposable>();
            bool called = false;
            var sub = new EventSubscription(() => called = true);
            sub.AddTo(list);
            Assert.AreEqual(1, list.Count, "AddTo(ICollection) 应将订阅添加到列表");
            list[0].Dispose();
            Assert.IsTrue(called);
        }

        // ── IntEventChannelSO ────────────────────────────────────────────────

        [Test]
        public void IntEventChannel_Raise_CallsAllSubscribers()
        {
            var channel = ScriptableObject.CreateInstance<IntEventChannelSO>();
            try
            {
                int sum = 0;
                channel.OnEventRaised += v => sum += v;
                channel.OnEventRaised += v => sum += v;
                channel.Raise(5);
                Assert.AreEqual(10, sum, "两个订阅者应各收到一次事件");
            }
            finally
            {
                Object.DestroyImmediate(channel);
            }
        }

        [Test]
        public void IntEventChannel_Raise_NoSubscribers_DoesNotThrow()
        {
            var channel = ScriptableObject.CreateInstance<IntEventChannelSO>();
            try
            {
                Assert.DoesNotThrow(() => channel.Raise(42));
            }
            finally
            {
                Object.DestroyImmediate(channel);
            }
        }

        [Test]
        public void IntEventChannel_UnsubscribeAfterDispose()
        {
            var channel = ScriptableObject.CreateInstance<IntEventChannelSO>();
            try
            {
                int callCount = 0;
                void Handler(int v) => callCount++;
                channel.OnEventRaised += Handler;
                channel.Raise(1);
                Assert.AreEqual(1, callCount);

                channel.OnEventRaised -= Handler;
                channel.Raise(1);
                Assert.AreEqual(1, callCount, "取消订阅后不应再收到事件");
            }
            finally
            {
                Object.DestroyImmediate(channel);
            }
        }

        // ── VoidEventChannelSO ───────────────────────────────────────────────

        [Test]
        public void VoidEventChannel_Raise_CallsSubscriber()
        {
            var channel = ScriptableObject.CreateInstance<VoidEventChannelSO>();
            try
            {
                bool received = false;
                channel.OnEventRaised += () => received = true;
                channel.Raise();
                Assert.IsTrue(received);
            }
            finally
            {
                Object.DestroyImmediate(channel);
            }
        }

        // ── ServiceLocator ───────────────────────────────────────────────────

        [SetUp]
        public void SetUp() => ServiceLocator.Reset();

        [TearDown]
        public void TearDown() => ServiceLocator.Reset();

        [Test]
        public void ServiceLocator_RegisterAndGet_ReturnsInstance()
        {
            var mock = new MockService();
            ServiceLocator.Register<IMockService>(mock);
            var retrieved = ServiceLocator.Get<IMockService>();
            Assert.AreSame(mock, retrieved);
        }

        [Test]
        public void ServiceLocator_GetUnregistered_ThrowsInvalidOperation()
        {
            Assert.Throws<InvalidOperationException>(
                () => ServiceLocator.Get<IMockService>());
        }

        [Test]
        public void ServiceLocator_GetOrDefault_Unregistered_ReturnsDefault()
        {
            var result = ServiceLocator.GetOrDefault<IMockService>();
            Assert.IsNull(result);
        }

        [Test]
        public void ServiceLocator_GetOrDefault_Registered_ReturnsInstance()
        {
            var mock = new MockService();
            ServiceLocator.Register<IMockService>(mock);
            var result = ServiceLocator.GetOrDefault<IMockService>();
            Assert.AreSame(mock, result);
        }

        [Test]
        public void ServiceLocator_RegisterIfAbsent_DoesNotOverwrite()
        {
            var first = new MockService();
            var second = new MockService();
            ServiceLocator.Register<IMockService>(first);
            ServiceLocator.RegisterIfAbsent<IMockService>(second);
            Assert.AreSame(first, ServiceLocator.Get<IMockService>(),
                "RegisterIfAbsent 不应覆盖已存在的注册");
        }

        [Test]
        public void ServiceLocator_Unregister_RemovesService()
        {
            ServiceLocator.Register<IMockService>(new MockService());
            ServiceLocator.Unregister<IMockService>();
            Assert.Throws<InvalidOperationException>(
                () => ServiceLocator.Get<IMockService>());
        }

        [Test]
        public void ServiceLocator_Unregister_WithWrongInstance_DoesNotRemove()
        {
            var first = new MockService();
            var second = new MockService();
            ServiceLocator.Register<IMockService>(first);
            ServiceLocator.Unregister<IMockService>(second); // 不同实例，不应移除
            Assert.AreSame(first, ServiceLocator.Get<IMockService>(),
                "错误实例的 Unregister 不应移除已注册的服务");
        }

        [Test]
        public void ServiceLocator_OverrideForTest_ReplacesService()
        {
            var original = new MockService { Value = 1 };
            var replacement = new MockService { Value = 99 };
            ServiceLocator.Register<IMockService>(original);
            ServiceLocator.OverrideForTest<IMockService>(replacement);
            Assert.AreEqual(99, ServiceLocator.Get<IMockService>().Value);
        }

        // ── Test Helpers ─────────────────────────────────────────────────────

        private interface IMockService { int Value { get; set; } }
        private class MockService : IMockService { public int Value { get; set; } }
    }
}
```

---

## 运行方式

1. 将上方代码保存至 `Assets/Tests/EditMode/EventSystemTests.cs`
2. 打开 `Window → General → Test Runner`
3. 选择 `EditMode` → 展开 `BaseGames.Tests.EditMode` → 展开 `EventSystemTests`
4. 点击 `Run All` 或逐个运行

### asmdef 配置确认

打开 `Assets/Tests/EditMode/BaseGames.Tests.EditMode.asmdef`，确认 `references` 数组包含：

```json
{
  "references": [
    "BaseGames.Core.Events",
    "BaseGames.Core",
    "BaseGames.Combat.StatusEffects"
  ],
  "includePlatforms": [],
  "excludePlatforms": [],
  "allowUnsafeCode": false,
  "overrideReferences": true,
  "precompiledReferences": ["nunit.framework.dll"],
  "autoReferenced": false,
  "defineConstraints": [],
  "versionDefines": [],
  "noEngineReferences": false
}
```

---

## 预期结果

所有 **20 个测试** 全部通过（绿色）。

若出现失败，常见原因：

| 失败现象 | 排查方向 |
|---------|---------|
| `ServiceLocator.Reset()` 方法不存在 | 检查 `#if UNITY_EDITOR` 编译条件是否生效（EditMode 测试应在 UNITY_EDITOR 下） |
| `IntEventChannelSO` 找不到 | 确认 asmdef references 已包含 `BaseGames.Core.Events` |
| `NullReferenceException` on `channel.Raise` | 确认使用 `ScriptableObject.CreateInstance<>()` 而非 `new` |