如何在 Unity 游戏引擎平台上的单元测试中实例化 MonoBehaviour 对象答案

【问题标题】：How to instantiate MonoBehaviour objects in a unit test on Unity Game Engine platform如何在 Unity 游戏引擎平台上的单元测试中实例化 MonoBehaviour 对象
【发布时间】：2016-01-10 17:32:18
【问题描述】：

我在 Github (game project) 上有以下开源项目。我目前正在尝试对使用 MSTest 框架编写的代码进行单元测试，但所有测试都返回相同的错误消息：“未处理的异常：System.Security.SecurityException：ECall 方法必须打包到系统模块中。”这发生在我尝试使用 NUnit 模板进行单元测试时。

我看过 ECall methods post must be packaged 找到一些答案，但我没有，因为 OP 说他的解决方案在调试器区域内但不在调试器区域内工作。就我而言，在查看帖子时，OP的问题没有得到解决。

之后，我在我的项目中导入了 UnityTestTools 框架。认为这很容易，因为它基于 NUnit 框架。事实证明，没有。测试本身是相当基础的。我有这个基类，称为 BaseCharacterClass:MonoBehavior，除其他外，它具有 BaseCharacterStats 类型的属性。在统计数据中，有一个 CharacterHealth 类型的对象，它负责照顾玩家的健康。

现在，当我在测试中尝试以下内容时，我似乎没有得到以下两个堆栈跟踪。

单元测试 (NUNIT)

使用 new 关键字创建 MonoBehavior 对象

[Test]
[Category("Mock Character")]
public void Mock_Character_With_No_Health()
{
    var mock = new MoqBaseCharacter ();
    Assert.NotNull (mock.BaseStats);
    Assert.NotNull (mock.BaseStats.Health);
    Assert.LessOrEqual (0, mock.BaseStats.Health.CurrentHealth);
}
//This is not the full file
//There "2" classes: 1 for holding tests and that Mock object 
public MoqBaseCharacter()
{
    this.BaseStats = new BaseCharacterStats ();
    this.BaseStats.Health = new CharacterHealth (0);
}

堆栈跟踪：

Mock_Character_With_No_Health (0.047s) --- System.NullReferenceException：对象引用未设置为对象的实例 --- 在 Assets.Scripts.CharactersUtil.CharacterHealth..ctor (Int32 sh) [0x0002f] 中 C:\Users\Kevin\Documents\AndroidPC_Prototype\PC_Augmented_Tactics_Demo\Assets\Scripts\CharactersUtil\CharacterHealth.cs:29

在 UnityTest.MoqBaseCharacter..ctor () [0x00011] 中 C:\Users\Kevin\Documents\AndroidPC_Prototype\PC_Augmented_Tactics_Demo\Assets\UnityTestTools\Examples\UnitTestExamples\Editor\SampleTests.cs:14

在 UnityTest.SampleTests.Mock_Character_With_No_Health () [0x00000] 中 C:\Users\Kevin\Documents\AndroidPC_Prototype\PC_Augmented_Tactics_Demo\Assets\UnityTestTools\Examples\UnitTestExamples\Editor\SampleTests.cs:32

使用 NSubstitute.For

[Test]
[Category("Mock Character")]
public void Mock_Character_With_No_Health()
{
    var mock = NSubstitute.Substitute.For<MoqBaseCharacter> ();
    Assert.NotNull (mock.BaseStats);
    Assert.NotNull (mock.BaseStats.Health);
    Assert.LessOrEqual (0, mock.BaseStats.Health.CurrentHealth);
}

堆栈跟踪

Mock_Character_With_No_Health (0.137s) --- System.Reflection.TargetInvocationException ：调用的目标已抛出异常。 ----> System.NullReferenceException：对象引用未设置为对象的实例 --- 在 System.Reflection.MonoCMethod.Invoke (System.Object obj, BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] 参数，System.Globalization.CultureInfo 文化） [0x0012c] 在 /Users/builduser/buildslave/mono-runtime-and-classlibs/build/mcs/class/corlib/System.Reflection/MonoMethod.cs:519

在 System.Reflection.MonoCMethod.Invoke (BindingFlags invokeAttr, System.Reflection.Binder 绑定器，System.Object[] 参数， System.Globalization.CultureInfo 文化）[0x00000] 在 /Users/builduser/buildslave/mono-runtime-and-classlibs/build/mcs/class/corlib/System.Reflection/MonoMethod.cs:528

在 System.Activator.CreateInstance（System.Type 类型，BindingFlags bindingAttr, System.Reflection.Binder binder, System.Object[] args, System.Globalization.CultureInfo 文化，System.Object[] 激活属性）[0x001b8] 在 /Users/builduser/buildslave/mono-runtime-and-classlibs/build/mcs/class/corlib/System/Activator.cs:338

在 System.Activator.CreateInstance（System.Type 类型，System.Object[] args, System.Object[] activationAttributes) [0x00000] in /Users/builduser/buildslave/mono-runtime-and-classlibs/build/mcs/class/corlib/System/Activator.cs:268

在 System.Activator.CreateInstance（System.Type 类型，System.Object[] args) [0x00000] 在 /Users/builduser/buildslave/mono-runtime-and-classlibs/build/mcs/class/corlib/System/Activator.cs:263

在 Castle.DynamicProxy.ProxyGenerator.CreateClassProxyInstance (System.Type proxyType, System.Collections.Generic.List`1 proxyArguments, System.Type classToProxy, System.Object[] constructorArguments) [0x00000] in :0

在 Castle.DynamicProxy.ProxyGenerator.CreateClassProxy (System.Type classToProxy，System.Type[] 附加InterfacesToProxy， Castle.DynamicProxy.ProxyGenerationOptions 选项，System.Object[] constructorArguments, Castle.DynamicProxy.IInterceptor[] 拦截器） [0x00000] 在 :0

在 NSubstitute.Proxies.CastleDynamicProxy.CastleDynamicProxyFactory.CreateProxyUsingCastleProxyGenerator (System.Type typeToProxy, System.Type[] 附加接口, System.Object[] constructorArguments, IInterceptor 拦截器, Castle.DynamicProxy.ProxyGenerationOptions proxyGenerationOptions) [0x00000] 在 :0

在 NSubstitute.Proxies.CastleDynamicProxy.CastleDynamicProxyFactory.GenerateProxy (ICallRouter callRouter, System.Type typeToProxy, System.Type[] AdditionalInterfaces, System.Object[] constructorArguments) [0x00000] 在：0

在 NSubstitute.Proxies.ProxyFactory.GenerateProxy (ICallRouter callRouter, System.Type typeToProxy, System.Type[] AdditionalInterfaces, System.Object[] constructorArguments) [0x00000] 在：0

在 NSubstitute.Core.SubstituteFactory.Create (System.Type[] typesToProxy, System.Object[] constructorArguments, SubstituteConfig config) [0x00000] in :0

在 NSubstitute.Core.SubstituteFactory.Create (System.Type[] typesToProxy, System.Object[] constructorArguments) [0x00000] in :0

在 NSubstitute.Substitute.For (System.Type[] typesToProxy, System.Object[] constructorArguments) [0x00000] in :0

在 NSubstitute.Substitute.For[MoqBaseCharacter] (System.Object[] constructorArguments) [0x00000] in :0

在 UnityTest.SampleTests.Mock_Character_With_No_Health () [0x00000] 中 C:\Users\Kevin\Documents\AndroidPC_Prototype\PC_Augmented_Tactics_Demo\Assets\UnityTestTools\Examples\UnitTestExamples\Editor\SampleTests.cs:32 --NullReferenceException

在 Assets.Scripts.CharactersUtil.CharacterHealth..ctor (Int32 sh) [0x0002f] 在 C:\Users\Kevin\Documents\AndroidPC_Prototype\PC_Augmented_Tactics_Demo\Assets\Scripts\CharactersUtil\CharacterHealth.cs:29

在 UnityTest.MoqBaseCharacter..ctor () [0x00011] 中 C:\Users\Kevin\Documents\AndroidPC_Prototype\PC_Augmented_Tactics_Demo\Assets\UnityTestTools\Examples\UnitTestExamples\Editor\SampleTests.cs:14

在 Castle.Proxies.MoqBaseCharacterProxy..ctor (ICallRouter , Castle.DynamicProxy.IInterceptor[] ) [0x00000] in :0

at（包装器托管到本机） System.Reflection.MonoCMethod:InternalInvoke (object,object[],System.Exception&)

在 System.Reflection.MonoCMethod.Invoke (System.Object obj, BindingFlags invokeAttr，System.Reflection.Binder 绑定器， System.Object[] 参数，System.Globalization.CultureInfo 文化） [0x00119] 在 /Users/builduser/buildslave/mono-runtime-and-classlibs/build/mcs/class/corlib/System.Reflection/MonoMethod.cs:513

免责声明

对NSubstitute 的快速阅读告诉我，我应该更好地为潜艇使用接口......在我的情况下，我真的不知道接口如何更适合我的代码。如果有人对此有想法而不是使用 new 关键字，我全力以赴！最后，这是 BaseCharacter、BaseStats 和 Health 的源代码

基本字符实现

using System;
using UnityEngine;
using System.Collections.Generic;
using JetBrains.Annotations;
using Random = System.Random;

namespace Assets.Scripts.CharactersUtil
{
    public class BaseCharacterClass : MonoBehaviour
    {
        //int[] basicUDLRMovementArray = new int[4];

        public List<BaseCharacterClass> CurrentEnnemies; 
        public int StartingHealth = 500;
        public BaseCharacterStats BaseStats { get; set; }

        // Use this for initialization
        private void Start()
        {
            BaseStats = new BaseCharacterStats {Health = new CharacterHealth(StartingHealth)}; //Testing purposes
            BaseStats.ChanceForCriticalStrike = new Random().Next(0,BaseStats.CriticalStrikeCounter);
        }

        // Update is called once per frame

        private void Update()
        {
            //ExecuteBasicMovement();

        }

        //During an attack with any kind of character
        //TODO: Make sure that people from the same team cannot attack themselves (friendly fire)
        private void OnTriggerEnter([NotNull] Collider other)
        {
            if (other == null) throw new ArgumentNullException(other.tag);
            Debug.Log("I'm about to receive some damage");
            var characterStats = other.gameObject.GetComponent<BaseCharacterClass>().BaseStats;
            var heathToAddOrRemove = other.gameObject.tag == "Healer" || other.gameObject.tag == "AIHealer" ? characterStats.Power : -1 * characterStats.Power;
            characterStats.Health.TakeDamageFromCharacter((int)heathToAddOrRemove);
            Debug.Log("I should have received damage from a bastard");
            if (characterStats.Health.CurrentHealth == 500)
            {
                Debug.Log("This is a mistake, I believe I'm a god! INVICIBLE");
            }
        }

        /*
        public void ExecuteBasicMovement()
        {
            var move = new Vector3(Input.GetAxis("Horizontal"), Input.GetAxis("Vertical"), 0);
            transform.position += move * BaseStats.Speed * Time.deltaTime;
        }

        //TODO: Make sure players moves correctly within the environment per cases
        public void ExecuteMovementPerCase()
        {
        }
        */

        public bool CanDoExtraDamage()
        {
            if (BaseStats.ChanceForCriticalStrike*BaseStats.Luck < 50) return false;
            BaseStats.CriticalStrikeCounter--;
            BaseStats.ChanceForCriticalStrike = new Random().Next(0, BaseStats.CriticalStrikeCounter);
            BaseStats.AjustCriticalStrikeChances(); 
            return true;
        }
    }
}

基础数据

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using JetBrains.Annotations;

namespace Assets.Scripts.CharactersUtil
{
    public class BaseCharacterStats
    {
        public float Power { get; set; }
        public float Defense { get; set; }
        public float Agility { get; set; }
        public float Speed { get; set; } 
        public float MagicPower { get; set; }
        public float MagicResist { get; set; }
        public int ChanceForCriticalStrike;
        public int Luck { get; set; }
        public int CriticalStrikeCounter = 20;
        public int TemporaryDefenseBonusValue;
        private Random _randomValueGenerator;

        public BaseCharacterStats()
        {
            _randomValueGenerator= new Random();
        }

        [NotNull]
        public CharacterHealth Health
        {
            get { return _health; }
            set { _health = value; }
        }
        private CharacterHealth _health;

        public void AjustCriticalStrikeChances()
        {
            if (CriticalStrikeCounter <= 5)
            {
                CriticalStrikeCounter = 5;
            }
        }

        public int DetermineDefenseBonusForTurn()
        {
            TemporaryDefenseBonusValue = _randomValueGenerator.Next(10,20);
            return TemporaryDefenseBonusValue;
        }
    }
}

健康

using JetBrains.Annotations;
using UnityEngine;
using UnityEngine.UI;

namespace Assets.Scripts.CharactersUtil
{
    public class CharacterHealth {
        public int StartingHealth { get; set; }
        public int CurrentHealth { get; set; }
        public Slider HealthSlider { get; set; }
        public bool isDead;
        public Color MaxHealthColor = Color.green;
        public Color MinHealthColor = Color.red;
        private int _counter;
        private const int MaxHealth = 200;
        public Image Fill;


        private void Awake() {
            //HealthSlider = GameObject.GetComponent<Slider>();
            _counter = MaxHealth;            // just for testing purposes
        }
        // Use this for initialization

        public CharacterHealth(int sh)
        {
            StartingHealth = sh;
            CurrentHealth = StartingHealth;
            HealthSlider.wholeNumbers = true; 
            HealthSlider.minValue = 0f;
            HealthSlider.maxValue = StartingHealth;
            HealthSlider.value = CurrentHealth; 
        }

        public void Start()
        {
            HealthSlider.wholeNumbers = true; 
            HealthSlider.minValue = 0f;
            HealthSlider.maxValue = MaxHealth;
            HealthSlider.value = MaxHealth;  
        }

        public void TakeDamageFromCharacter([NotNull] BaseCharacterClass baseCharacter)
        {
            CurrentHealth -= (int)baseCharacter.BaseStats.Power;
            HealthSlider.value = CurrentHealth;
            UpdateHealthBar ();
            if (CurrentHealth <= 0)
                isDead = true;
        }

        public void TakeDamageFromCharacter(int characterStrength)
        {
            CurrentHealth -= characterStrength;
            HealthSlider.value = CurrentHealth;
            UpdateHealthBar ();
            if (CurrentHealth <= 0)
                isDead = true;
        }

        public void RestoreHealth(BaseCharacterClass bs)
        {
            CurrentHealth += (int)bs.BaseStats.Power;
            HealthSlider.value = CurrentHealth;
            UpdateHealthBar ();
        }
        public void RestoreHealth(int characterStrength)
        {
            CurrentHealth += characterStrength;
            HealthSlider.value = CurrentHealth;
            UpdateHealthBar ();
        }
        public void UpdateHealthBar() {
            Fill.color = Color.Lerp(MinHealthColor, MaxHealthColor, (float)CurrentHealth / MaxHealth);
        }
    }
}

【问题讨论】：

我可能是错的，但问题本身很可能是由于您正在尝试创建 MonoBehavior 对象的新实例。你永远不应该自己做，因为 Unity 需要为你做这件事，因为有很多底层组件需要放在正确的位置才能让一切正常工作。所以在写单元测试的时候，不能自己测试MonoBehaviors，你必须把“核心游戏逻辑”放在各自的类中，单独测试；并且在单一行为中只有“图形游戏逻辑”。然后你就可以运行你的单元测试了:-)
另一件事是，您在 CharacterHealth 类的构造函数中引用了“HealthSlider”，这是一个统一的 UI 滑块；并且您没有在代码中的任何位置设置引用。所以那个对象是NULL。并且会抛出 NullPointerException。
我应该如何修改我写的代码？
基本上，我的 BaseCharacterClass（所有人类玩家和我的 AI 类都继承的类）应该是 MonoBehaviour 子类吗？ @KarlPatrikJohansson
你的 BaseCharacterClass 不应该是 MonoBehavior，而是将所有需要成为 monobehavior 的代码放在它自己的 MonoBehavior 中，并从中引用 BaseCharacterClass。例如，当获取另一个玩家的统计数据时（在您的OnTriggerEnter 中），您将改为使用var characterStats = other.gameObject.GetComponent<CharacterWrapperScript>().BaseCharacterClass.BaseStats;。并将 BaseCharacterClass 的逻辑与您从 MonoBehavior 获得的交互分开。

标签： c# .net unit-testing unity3d

【解决方案1】：

基本字符

用于单元测试的类

public class BaseCharacterClass 
{
    public BaseCharacterStats BaseStats { get; set; }
    public BaseCharacterClass(int startingHealth) 
    {
        BaseStats = new BaseCharacterStats {Health = new CharacterHealth(startingHealth)}; //Testing purposes
        BaseStats.ChanceForCriticalStrike = new Random().Next(0,BaseStats.CriticalStrikeCounter);
    }

    public bool CanDoExtraDamage() 
    {
        if (BaseStats.ChanceForCriticalStrike*BaseStats.Luck < 50) return false;
        BaseStats.CriticalStrikeCounter--;
        BaseStats.ChanceForCriticalStrike = new Random().Next(0, BaseStats.CriticalStrikeCounter);
        BaseStats.AjustCriticalStrikeChances(); 
        return true;
    }
}

用于您的角色/AI/NPCS 的新 MonoBehavior 脚本

using System;
using UnityEngine;
using System.Collections.Generic;
using JetBrains.Annotations;
using Random = System.Random;

namespace Assets.Scripts.CharactersUtil
{
    public class BaseCharacterClassWrapper : MonoBehaviour
    {
        //int[] basicUDLRMovementArray = new int[4];

        public List<BaseCharacterClass> CurrentEnnemies; 
        public int StartingHealth = 500;        

        public BaseCharacterClass CharacterClass;


        public CharacterHealthUI HealthUI;

        // Use this for initialization
        private void Start()
        {
            CharacterClass = new BaseCharacterClass(StartingHealth);  
            HealthUI = this.GetComponent<CharacterHealthUI>();
            HealthUI.CharacterHealth = CharacterClass.BaseStats.Health;
        }

        // Update is called once per frame

        private void Update()
        {
            //ExecuteBasicMovement();
        }

        //During an attack with any kind of character
        //TODO: Make sure that people from the same team cannot attack themselves (friendly fire)
        private void OnTriggerEnter([NotNull] Collider other)
        {
            if (other == null) throw new ArgumentNullException(other.tag);
            Debug.Log("I'm about to receive some damage");

            var characterStats = other.gameObject.GetComponent<BaseCharacterClassWrapper>().CharacterClass.BaseStats;

            var healthToAddOrRemove = other.gameObject.tag == "Healer" || other.gameObject.tag == "AIHealer" ? characterStats.Power : -1 * characterStats.Power;

            characterStats.Health.TakeDamageFromCharacter((int)healthToAddOrRemove);

            Debug.Log("I should have received damage from a bastard");

            if (characterStats.Health.CurrentHealth == 500)
            {
                Debug.Log("This is a mistake, I believe I'm a god! INVICIBLE");
            }
        }

        /*
        public void ExecuteBasicMovement()
        {
            var move = new Vector3(Input.GetAxis("Horizontal"), Input.GetAxis("Vertical"), 0);
            transform.position += move * BaseStats.Speed * Time.deltaTime;
        }

        //TODO: Make sure players moves correctly within the environment per cases
        public void ExecuteMovementPerCase()
        {
        }
        */



        public bool CanDoExtraDamage()
        {
            return CharacterClass.CanDoExtraDamage();
        }
    }
}

健康

将此用于您的健康 UI

using JetBrains.Annotations;
using UnityEngine;
using UnityEngine.UI;

namespace Assets.Scripts.CharactersUtil
{
    public class CharacterHealthUI : MonoBehavior {
      public Image Fill;
      public Color MaxHealthColor = Color.green;
      public Color MinHealthColor = Color.red;   
      public Slider HealthSlider;

      private void Start() {
          if(!HealthSlider) {
            HealthSlider = this.GetComponent<Slider>();            
          }
          if(!Fill) {
            Fill = this.GetComponent<Image>();
          }          
      }

      private CharacterHealth _charaHealth;
      public CharacterHealth CharacterHealth { 
        get { return _charaHealth; }
        set { 
        if(_charaHealth!=null)
            _charaHealth.HealthChanged -= HealthChanged;
          _charaHealth = value; 
          _charaHealth.HealthChanged += HealthChanged;
        }
      }

      public HealthChanged(object sender, HealthChangedEventArgs hp) {
            HealthSlider.wholeNumbers = true; 
            HealthSlider.minValue = hp.MinHealth;
            HealthSlider.maxValue = hp.MaxHealth;
            HealthSlider.value = hp.CurrentHealth;  
            Fill.color = Color.Lerp(MinHealthColor, MaxHealthColor, (float)hp.CurrentHealth / hp.MaxHealth);
      }

    }

}

最后，你的健康逻辑 :-)

using JetBrains.Annotations;
using UnityEngine;
using UnityEngine.UI;

namespace Assets.Scripts.CharactersUtil
{      

    public class HealthChangedEventArgs : EventArgs 
    {
        public float MinHealth { get; set; }
        public float MaxHealth { get; set; }
        public float CurrentHealth { get; set;}
        public HealthChangedEventArgs(float minHealth, float curHealth, float maxHealth) {
            MinHealth = minHealth;
            CurrentHealth = curHealth;
            MaxHealth = maxHealth;
        }
    }


    public class CharacterHealth {
        public int StartingHealth { get; set; }

        private int _currentHealth;
        public int CurrentHealth 
        { 
          get { return _currentHealth; } 
          set { 
              _currentHealth = value;
              if(HealthChanged!=null)
                HealthChanged(this, new HealthChangedEventArgs(0f, _currentHealth, MaxHealth);
            }
        }      

        public bool isDead;

        private int _counter;
        private const int MaxHealth = 200;

        public event EventHandler<HealthChangedEventArgs> HealthChanged;

        // Use this for initialization

        public CharacterHealth(int sh)
        {
            StartingHealth = sh;
            CurrentHealth = StartingHealth;
        }

        public void TakeDamageFromCharacter([NotNull] BaseCharacterClass baseCharacter)
        {
            CurrentHealth -= (int)baseCharacter.BaseStats.Power;        
            if (CurrentHealth <= 0)
                isDead = true;
        }

        public void TakeDamageFromCharacter(int characterStrength)
        {
            CurrentHealth -= characterStrength;
            if (CurrentHealth <= 0)
                isDead = true;
        }

        public void RestoreHealth(BaseCharacterClass bs)
        {
            CurrentHealth += (int)bs.BaseStats.Power;
        }
        public void RestoreHealth(int characterStrength)
        {
            CurrentHealth += characterStrength;
        }
    }
}

这应该使您可以对游戏逻辑进行单元测试:-)

虽然我还没有测试过，所以我不能肯定它会起作用。但从逻辑上讲（至少在我的脑海中）它应该。

最大的不同是你想在你的游戏对象上使用BaseCharacterClassWrapper 和CharacterHealthUI 来实现想要的行为。然后单元测试继续BaseCharacterClass 和CharacterHealth

我希望这会有所帮助！

【讨论】：

所以，如果我做对了，我的单元测试，在这种情况下，我所要做的就是定位 BaseCharacter 和 CharacterHealth 但是当我将脚本提供给 GameObjects 时，我提供了 Wrapper 和 UI脚本^
从 CharacterHealth 中，您删除了 Image 和 Slider 字段以及健康栏将如何更新为当前健康状况。我该怎么办？
我添加了一个名为 HealthChanged 的事件，它会在每次更改健康状况时触发，这也会为您更新 Healthbar（您的滑块）。所以你不必在你的健康逻辑中考虑那部分。隔离不同区域，使逻辑本身可测试:-)

【解决方案2】：

还有另一个选项可以在不调用构造函数的情况下对 MonoBehaviours 进行单元测试（使用 FormatterServices）。这是一个创建可测试的 MonoBehaviours 的小助手类：

public static class TestableObjectFactory {
    public static T Create<T>() {
        return FormatterServices.GetUninitializedObject(typeof(T)).CastTo<T>();
    }
}

用法：

var testableObject = TestableObjectFactory.Create<MyMonoBehaviour>();
testableObject.Test();

【讨论】：