TypeLoadException using Moq on internal interface in signed assembly

Question

I am using the latest Moq (4.2.1502.911) in Visual Studio 2013 to mock an internal interface contained in another project. Both projects are signed with the same key. After searching here and elsewhere on the web I figured I had to add InternalsVisibleTo for the test assembly and "DynamicProxyGenAssembly2", using Moq's public key like so:

[assembly: InternalsVisibleTo("UnitTestProject1, PublicKey=00240000048000009...
[assembly: InternalsVisibleTo("DynamicProxyGenAssembly2, PublicKey=002400000...

Now when I run my test method I still get the following error:

Test Name:  TestMethod1
Test FullName:  UnitTestProject1.Class1Test.TestMethod1
Test Source:    c:\Users\******\Documents\Visual Studio 2013\Projects\MoqTest\UnitTestProject1\UnitTest1.cs : line 13
Test Outcome:   Failed
Test Duration:  0:00:00,0693592

Result Message: 
Test method UnitTestProject1.Class1Test.TestMethod1 threw exception: 
System.TypeLoadException: Le type 'Castle.Proxies.IFooProxy' de l'assembly 'DynamicProxyGenAssembly2, Version=0.0.0.0, Culture=neutral, PublicKeyToken=a621a9e7e5c32e69' essaye d'implémenter une interface inaccessible.
Result StackTrace:  
à System.Reflection.Emit.TypeBuilder.TermCreateClass(RuntimeModule module, Int32 tk, ObjectHandleOnStack type)
   à System.Reflection.Emit.TypeBuilder.CreateTypeNoLock()
   à System.Reflection.Emit.TypeBuilder.CreateType()
   à Castle.DynamicProxy.Generators.Emitters.AbstractTypeEmitter.CreateType(TypeBuilder type)
   à Castle.DynamicProxy.Generators.Emitters.AbstractTypeEmitter.BuildType()
   à Castle.DynamicProxy.Generators.InterfaceProxyWithoutTargetGenerator.GenerateType(String typeName, Type proxyTargetType, Type[] interfaces, INamingScope namingScope)
   à Castle.DynamicProxy.Generators.InterfaceProxyWithTargetGenerator.<>c__DisplayClass1.<GenerateCode>b__0(String n, INamingScope s)
   à Castle.DynamicProxy.Generators.BaseProxyGenerator.ObtainProxyType(CacheKey cacheKey, Func`3 factory)
   à Castle.DynamicProxy.Generators.InterfaceProxyWithTargetGenerator.GenerateCode(Type proxyTargetType, Type[] interfaces, ProxyGenerationOptions options)
   à Castle.DynamicProxy.DefaultProxyBuilder.CreateInterfaceProxyTypeWithoutTarget(Type interfaceToProxy, Type[] additionalInterfacesToProxy, ProxyGenerationOptions options)
   à Castle.DynamicProxy.ProxyGenerator.CreateInterfaceProxyWithoutTarget(Type interfaceToProxy, Type[] additionalInterfacesToProxy, ProxyGenerationOptions options, IInterceptor[] interceptors)
   à Moq.Proxy.CastleProxyFactory.CreateProxy(Type mockType, ICallInterceptor interceptor, Type[] interfaces, Object[] arguments)
   à Moq.Mock`1.<InitializeInstance>b__2()
   à Moq.PexProtector.Invoke(Action action)
   à Moq.Mock`1.InitializeInstance()
   à Moq.Mock`1.OnGetObject()
   à Moq.Mock`1.get_Object()
   à UnitTestProject1.Class1Test.TestMethod1() dans c:\Users\******\Documents\Visual Studio 2013\Projects\MoqTest\UnitTestProject1\UnitTest1.cs:ligne 15

(In English: System.TypeLoadException : Type 'Castle.Proxies.IFooProxy' from assembly 'DynamicProxyGenAssembly2, Version=0.0.0.0, Culture=neutral, PublicKeyToken=a621a9e7e5c32e69' is attempting to implement an inaccessible interface.)

Is there something else to do to get this to work? Here is a minimal compilable example: https://www.dropbox.com/s/c2slwq4do5ttp9p/MoqTest.zip?dl=0

You can't derive from internal interface... Following question http://stackoverflow.com/questions/8606412/create-type-that-implements-internal-interface may give you some hope... — Alexei Levenkov, May 06 '15 at 23:08
Not true, that's what InternalsVisibleToAttribute is for. The above works when the assemblies are not signed. — Asik, May 06 '15 at 23:14
So you are able to change "another" project - did not realize that. Note that your sample shows different public key from error... Usually test/proxy assemblies are not signed - you may need to actually manually build proxy that is signed with correct key for this to work. — Alexei Levenkov, May 06 '15 at 23:51

lawst · Accepted Answer · 2015-05-07T09:47:31.480

Using the following Public Key value solved the issue for me:

0024000004800000940000000602000000240000525341310004000001000100c547cac37abd99c8db225ef2f6c8a3602f3b3606cc9891605d02baa56104f4cfc0734aa39b93bf7852f7d9266654753cc297e7d2edfe0bac1cdcf9f717241550e0a7b191195b7667bb4f64bcb8e2121380fd1d9d46ad2d92d2d15605093924cceaf74c4861eff62abf69b9291ed0a340e113be11e6a7d3113e92484cf7045cc7

I initially tried to get the public key using sn.exe but I think the public key it returns is for Moq rather than DynamicProxyGenAssembly2. I got the above key from the Moq GitHub page:

https://github.com/Moq/moq4/wiki/Quickstart

// This assembly is the default dynamic assembly generated Castle DynamicProxy, 
// used by Moq. Paste in a single line.   
[assembly:InternalsVisibleTo("DynamicProxyGenAssembly2,PublicKey=0024000004800000940000000602000000240000525341310004000001000100c547cac37abd99c8db225ef2f6c8a3602f3b3606cc9891605d02baa56104f4cfc0734aa39b93bf7852f7d9266654753cc297e7d2edfe0bac1cdcf9f717241550e0a7b191195b7667bb4f64bcb8e2121380fd1d9d46ad2d92d2d15605093924cceaf74c4861eff62abf69b9291ed0a340e113be11e6a7d3113e92484cf7045cc7")]

TypeLoadException using Moq on internal interface in signed assembly

1 Answers1