.NET 8 Moq mock GetRequiredKeyedService Setup报错
.NET 8 Moq mock GetRequiredKeyedService Setup报错
项目代码里有地方用到IServiceProvider.GetRequiredKeyedService<T>
来解析服务,在写单元测试时需要Mock它,本以为像下面这样写就可以了:
var serviceProvider = new Mock<IServiceProvider>(); serviceProvider.Setup(x => x.GetRequiredKeyedService<AAA>(It.IsAny<BBB>())).Returns(new CCC());
没想到报错了:
Test method threw exception: System.NotSupportedException: Unsupported expression: x => x.GetRequiredKeyedService(It.IsAny<Type>(), It.IsAny<object>()) Extension methods (here: ServiceProviderKeyedServiceExtensions.GetRequiredKeyedService) may not be used in setup / verification expressions. Stack Trace: Guard.IsOverridable(MethodInfo method, Expression expression) line 87 MethodExpectation.ctor(LambdaExpression expression, MethodInfo method, IReadOnlyList`1 arguments, Boolean exactGenericTypeArguments, Boolean skipMatcherInitialization, Boolean allowNonOverridable) line 236 ExpressionExtensions.<Split>g__Split|5_0(Expression e, Expression& r, MethodExpectation& p, Boolean assignment, Boolean allowNonOverridableLastProperty) line 256 ExpressionExtensions.Split(LambdaExpression expression, Boolean allowNonOverridableLastProperty) line 170 Mock.SetupRecursive[TSetup](Mock mock, LambdaExpression expression, Func`4 setupLast, Boolean allowNonOverridableLastProperty) line 728 Mock.Setup(Mock mock, LambdaExpression expression, Condition condition) line 562 Mock`1.Setup[TResult](Expression`1 expression) line 645
有点奇怪,难道GetRequiredKeyedService
不是接口方法?查看.NET源代码,果然,GetRequiredKeyedService
是IServiceProvider的扩展方法,而我们知道Moq是不支持Setup扩展方法的。
/// <summary> /// Get service of type <typeparamref name="T"/> from the <see cref="IServiceProvider"/>. /// </summary> /// <typeparam name="T">The type of service object to get.</typeparam> /// <param name="provider">The <see cref="IServiceProvider"/> to retrieve the service object from.</param> /// <param name="serviceKey">An object that specifies the key of service object to get.</param> /// <returns>A service object of type <typeparamref name="T"/>.</returns> /// <exception cref="System.InvalidOperationException">There is no service of type <typeparamref name="T"/>.</exception> public static T GetRequiredKeyedService<T>(this IServiceProvider provider, object? serviceKey) where T : notnull { ThrowHelper.ThrowIfNull(provider); return (T)provider.GetRequiredKeyedService(typeof(T), serviceKey); }
原因找到就好办了,翻看源码,一步步找到IServiceProvider.GetRequiredKeyedService
首先看下requiredServiceSupportingProvider.GetRequiredKeyedService(serviceType, serviceKey)调的是什么方法
/// <summary> /// IKeyedServiceProvider is a service provider that can be used to retrieve services using a key in addition /// to a type. /// </summary> public interface IKeyedServiceProvider : IServiceProvider { /// <summary> /// Gets the service object of the specified type. /// </summary> /// <param name="serviceType">An object that specifies the type of service object to get.</param> /// <param name="serviceKey">An object that specifies the key of service object to get.</param> /// <returns> A service object of type serviceType. -or- null if there is no service object of type serviceType.</returns> object? GetKeyedService(Type serviceType, object? serviceKey); /// <summary> /// Gets service of type <paramref name="serviceType"/> from the <see cref="IServiceProvider"/> implementing /// this interface. /// </summary> /// <param name="serviceType">An object that specifies the type of service object to get.</param> /// <param name="serviceKey">The <see cref="ServiceDescriptor.ServiceKey"/> of the service.</param> /// <returns>A service object of type <paramref name="serviceType"/>. /// Throws an exception if the <see cref="IServiceProvider"/> cannot create the object.</returns> object GetRequiredKeyedService(Type serviceType, object? serviceKey); }
可以看到IKeyedServiceProvider也是继承了IServiceProvider接口,这就更好办了,我们直接Mock IKeyedServiceProvider再Setup即可,将用到IServiceProvider的地方,换成IKeyedServiceProvider。
代码如下:
var serviceProvider = new Mock<IKeyedServiceProvider>(); serviceProvider.Setup(x => x.GetRequiredKeyedService(It.IsAny<AAA>(), It.IsAny<BBB>())).Returns(new CCC());
运行测试,完美。
总结
解决这个问题并不困难,但是如果.Net不开源,看不到源代码,还是有点头疼。
作者: 马行空的博客
出处: https://www.cnblogs.com/netry/p/18388859/dotnet-moq-mock-GetRequiredKeyedService
本文版权归作者和博客园共有,欢迎转载,但未经作者同意必须保留此段声明,且在文章页面明显位置给出原文链接。
【推荐】编程新体验,更懂你的AI,立即体验豆包MarsCode编程助手
【推荐】凌霞软件回馈社区,博客园 & 1Panel & Halo 联合会员上线
【推荐】抖音旗下AI助手豆包,你的智能百科全书,全免费不限次数
【推荐】博客园社区专享云产品让利特惠,阿里云新客6.5折上折
【推荐】轻量又高性能的 SSH 工具 IShell:AI 加持,快人一步
· 微软正式发布.NET 10 Preview 1:开启下一代开发框架新篇章
· C# 集成 DeepSeek 模型实现 AI 私有化(本地部署与 API 调用教程)
· DeepSeek R1 简明指南:架构、训练、本地部署及硬件要求
· 没有源码,如何修改代码逻辑?
· NetPad:一个.NET开源、跨平台的C#编辑器