MoQ不设置Returns方法

Question

你好，我正在使用最小起订量，我想了解为什么我的方法的 return 值会被使用。在下面的示例中，我正在使用模拟接口 dependency.I 创建服务，我正在设置接口方法应该 return 的内容。但是，当服务使用我的模拟依赖项时， return 值为 null ，而不是我在 Returns 方法中设置的值。为什么会这样？

型号

public class SomeModel
{
  public string Name {get;set;}
}

模拟依赖

public interface IDependency
{
    Task<SomeModel> GetByIdAsync(string input);
}

使用模拟依赖的服务

public class SomeService
{
  private IDependency dependency;
  public SomeService(IDependency dependency)
  {
    this.dependency=dependency;
  }
  public async Task<SomeModel> GetByIdAsync(string id)
  {
     var model=await this.dependency.GetByIdAsync(id); //why is the result null , i have set the `Returns`
     if(model==null)
     {
        throw new NotSupportedException();
     }
     return model;
  }
}

测试class

public class MyTest
{
  [Testcase("data")]
  public async Task CanGetById(string value)
  {
      var model=new SomeModel{Name=value};
      var dependency=new Mock<IDependency>();
      dependency.Setup(x=>x.GetByIdAsync(value)).Returns(Task.FromResult(model)).Verifiable(); //i have set up the return of the dependency
      var service=new SomeService(dependency.Object);
      var clone=await service.GetByIdAsync(value);
      dependency.Verify();
  }
}

Answer 1

只有在调用时传递给模拟成员的值与设置模拟时的预期值不匹配时，结果才会为 null

除了使用 ReturnsAsync

之外，还有其他选择

例如

[Testcase("data")]
public async Task CanGetById(string value) {
    //Arrange
    var model = new SomeModel { Name = value };
    var dependency = new Mock<IDependency>();
    dependency
        .Setup(x => x.GetByIdAsync(value))
        .ReturnsAsync(model)
        .Verifiable(); 

    var service = new SomeService(dependency.Object);

    //Act
    var clone = await service.GetByIdAsync(value);

    //Assert
    dependency.Verify();
}

MoQ不设置Returns方法

MoQ does not set the Returns method

c#

unit-testing

moq

.net-core