How to mock ISerializable classes with Moq?

Question

Hi there,

I'm completly new to Moq and now trying to create a mock for System.Reflection.Assembly class. I'm using this code:

var mockAssembly = new Mock<Assembly>(); 
mockAssembly.Setup( x => x.GetTypes() ).Returns( new Type[] { 
    typeof( Type1 ), 
    typeof( Type2 ) 
} );

But when I run tests I get next exception:

System.ArgumentException : The type System.Reflection.Assembly 
implements ISerializable, but failed to provide a deserialization 
constructor 
Stack Trace: 
   at 
Castle.DynamicProxy.Generators.BaseProxyGenerator.VerifyIfBaseImplementsGet­ObjectData(Type 
baseType) 
   at 
Castle.DynamicProxy.Generators.ClassProxyGenerator.GenerateCode(Type[] 
interfaces, ProxyGenerationOptions options) 
   at Castle.DynamicProxy.DefaultProxyBuilder.CreateClassProxy(Type 
classToProxy, Type[] additionalInterfacesToProxy, 
ProxyGenerationOptions options) 
   at Castle.DynamicProxy.ProxyGenerator.CreateClassProxy(Type 
classToProxy, Type[] additionalInterfacesToProxy, 
ProxyGenerationOptions options, Object[] constructorArguments, 
IInterceptor[] interceptors) 
   at Moq.Proxy.CastleProxyFactory.CreateProxy[T](ICallInterceptor 
interceptor, Type[] interfaces, Object[] arguments) 
   at Moq.Mock`1.<InitializeInstance>b__0() 
   at Moq.PexProtector.Invoke(Action action) 
   at Moq.Mock`1.InitializeInstance() 
   at Moq.Mock`1.OnGetObject() 
   at Moq.Mock`1.get_Object() 

Could you reccomend me the right way to mock ISerializable classes (like System.Reflection.Assembly) with Moq.

Thanks in advance!

Answer 1

The issue is not with ISerializable interface. You can mock ISerializable classes.

Notice the exception message:

The type System.Reflection.Assembly implements ISerializable, but failed to provide a deserialization constructor

Problem is, that Assembly does not provide deserialization constructor.

Answer 2

Instead of a mock you could try creating a dynamic assembly and build from that.

var appDomain = AppDomain.CurrentDomain;
var assembly = appDomain.DefineDynamicAssembly(new AssemblyName("Test"), AssemblyBuilderAccess.ReflectionOnly);