How to mock web service call with Moq?

Question

The using below hits an external resource that I do not want to actually hit. I want to test someResult and the code that uses it, but every time I run my unit test, this code still tries to hit the real web service. How do I use moq to fake the real call to the web service, but not mock the rest of the code within the using?

public IMyInterface.SomeMethod()
{    
     // hits a web service
     using ( mySoapClient client = new mySoapClient() )
     {
          var someResult = client.DoSomething();
       ...
       ...
     }
}


[TestMethod()]
public void SomeMethodTest()
{
    IMyInterface target = new MyInterface();
    target.SomeMethod();

    // Assert....
}

Answer 1

You need to decouple the web service implementation from the consumer

public class ClassIWantToTest
{
      public ClassIWantToTest(IServiceIWantToCall service) {}

      public void SomeMethod()
      {
           var results = service.DoSomething();
           //Rest of the logic here
      }
}

Now you can use Moq to mock the IServiceIWantToCall in order to test the logic of SomeMethod

Answer 2

To add to pickles' answer, I created an interface for my current service calls named IService. I then created a ServiceMock class that inherits the interface and added a global variable named _service. In the constructor I instantiate the mock service and set up all the methods of the interface as such:

public class ServiceMock : IService
{
    Mock<IService> _serviceMock;

    public ServiceMock()
    {
        _serviceMock = new Mock<IService>();

        _serviceMock.Setup(x => x.GetString()).Returns("Default String");

        SomeClass someClass = new SomeClass();
        someClass.Property1= "Default";
        someClass.Property2= Guid.NewGuid().ToString();

        _serviceMock.Setup(x => x.GetSomeClass()).Returns(someClass);
    }

    public string GetString()
    {
        return _serviceMock.Object.GetString();
    }

    public License GetSomeClass()
    {
        return _serviceMock.Object.GetSomeClass();
    }
}

You then inject this class into your code instead of the actual web service. It will return the values you set it up to return. You can now test without depending on your web service.