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

Question

我在 Github 上有以下开源项目 ( game project )。我目前正在尝试对我使用 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。”当我尝试使用 NUnit 模板进行单元测试时，发生了这种情况。

我浏览过 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有效，但在调试器区域外无效。就我而言，在查看该帖子时，OP 的问题尚未解决。

之后，我将 UnityTestTools 框架导入到我的项目中。我认为这很容易，因为它基于 NUnit 框架。事实证明没有。该测试本身是相当基础的。我有一个名为 BaseCharacterClass:MonoBehavior 的基类，除其他外，它还具有 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状况。

现在，我有以下两个堆栈跟踪，当我在测试中尝试以下操作时，我似乎没有得到它们。

单元测试 (NUNIT)

1. 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 : Object reference not set to an instance of an object --- at Assets.Scripts.CharactersUtil.CharacterHealth..ctor (Int32 sh) [0x0002f] in C:\Users\Kevin\Documents\AndroidPC_Prototype\PC_Augmented_Tactics_Demo\Assets\Scripts\CharactersUtil\CharacterHealth.cs:29

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

at UnityTest.SampleTests.Mock_Character_With_No_Health () [0x00000] in 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 : Exception has been thrown by the target of an invocation. ----> System.NullReferenceException : Object reference not set to an instance of an object --- at System.Reflection.MonoCMethod.Invoke (System.Object obj, BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) [0x0012c] in /Users/builduser/buildslave/mono-runtime-and-classlibs/build/mcs/class/corlib/System.Reflection/MonoMethod.cs:519

at System.Reflection.MonoCMethod.Invoke (BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) [0x00000] in /Users/builduser/buildslave/mono-runtime-and-classlibs/build/mcs/class/corlib/System.Reflection/MonoMethod.cs:528

at System.Activator.CreateInstance (System.Type type, BindingFlags bindingAttr, System.Reflection.Binder binder, System.Object[] args, System.Globalization.CultureInfo culture, System.Object[] activationAttributes) [0x001b8] in /Users/builduser/buildslave/mono-runtime-and-classlibs/build/mcs/class/corlib/System/Activator.cs:338

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

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

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

at Castle.DynamicProxy.ProxyGenerator.CreateClassProxy (System.Type classToProxy, System.Type[] additionalInterfacesToProxy, Castle.DynamicProxy.ProxyGenerationOptions options, System.Object[] constructorArguments, Castle.DynamicProxy.IInterceptor[] interceptors) [0x00000] in :0

at NSubstitute.Proxies.CastleDynamicProxy.CastleDynamicProxyFactory.CreateProxyUsingCastleProxyGenerator (System.Type typeToProxy, System.Type[] additionalInterfaces, System.Object[] constructorArguments, IInterceptor interceptor, Castle.DynamicProxy.ProxyGenerationOptions proxyGenerationOptions) [0x00000] in :0

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

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

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

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

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

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

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

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

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

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

at (wrapper managed-to-native) System.Reflection.MonoCMethod:InternalInvoke (object,object[],System.Exception&)

at System.Reflection.MonoCMethod.Invoke (System.Object obj, BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) [0x00119] in /Users/builduser/buildslave/mono-runtime-and-classlibs/build/mcs/class/corlib/System.Reflection/MonoMethod.cs:513

免责声明

快速阅读NSubstitute告诉我，我应该更好地使用接口(interface)来代替...在我的情况下，我真的不知道接口(interface)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，我会全力以赴!最后，这是 BaseCharacter、BaseStats 和 Health 的源代码

基本角色实现

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;
        }
    }
}

基础统计数据

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);
        }
    }
}

Answer 1

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 的小帮助器类:

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();