Moq access method failed for internal constructors

[jdbriaris]

I've been attempting to use moq to mock a class with an internal constructor. Following on from my SO post i appear to be hitting the constructor, but now faced with a new error, i.e.,

System.MethodAccessException
Attempt by method 'Castle.Proxies.MyClassProxy..ctor(Castle.DynamicProxy.IInterceptor[])'
to access method 'MyAssembly.MyClass..ctor()' failed.
at Castle.Proxies.StageProxy..ctor(IInterceptor[] )
--- End of inner exception stack trace ---
at System.RuntimeMethodHandle.InvokeMethod(Object target, Object[] >arguments, Signature sig, Boolean constructor)
at System.Reflection.RuntimeConstructorInfo.Invoke(BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
at System.RuntimeType.CreateInstanceImpl(BindingFlags bindingAttr, Binder binder, Object[] args, CultureInfo culture, Object[] activationAttributes, StackCrawlMark& stackMark)
at System.Activator.CreateInstance(Type type, BindingFlags bindingAttr, Binder binder, Object[] args, CultureInfo culture, Object[] activationAttributes)
at System.Activator.CreateInstance(Type type, Object[] args)
at Castle.DynamicProxy.ProxyGenerator.CreateClassProxyInstance(Type proxyType, List1 proxyArguments, Type classToProxy, Object[] constructorArguments) at Castle.DynamicProxy.ProxyGenerator.CreateClassProxy(Type classToProxy, Type[] additionalInterfacesToProxy, ProxyGenerationOptions options, Object[] constructorArguments, IInterceptor[] interceptors) at Moq.Proxy.CastleProxyFactory.CreateProxy(Type mockType, ICallInterceptor interceptor, Type[] interfaces, Object[] arguments) at Moq.Mock1.b__20_0()
at Moq.PexProtector.Invoke(Action action)
at Moq.Mock1.InitializeInstance() at Moq.Mock1.OnGetObject()
at Moq.Mock`1.get_Object()
at TestAssembly.UnitTest1.TestMethod1() in c:\users\briaris-j\documents\visual studio 2017\Projects\TestMoqInternals\TestAssembly\UnitTest1.cs:line 16

This is my AssemblyInfo.cs for MyAssembly, i.e., the assembly containing my internal types

using System.Reflection;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;

// General Information about an assembly is controlled through the following
// set of attributes. Change these attribute values to modify the information
// associated with an assembly.
[assembly: AssemblyTitle("MyAssembly")]
[assembly: AssemblyDescription("")]
[assembly: AssemblyConfiguration("")]
[assembly: AssemblyCompany("")]
[assembly: AssemblyProduct("MyAssembly")]
[assembly: AssemblyCopyright("Copyright ©  2017")]
[assembly: AssemblyTrademark("")]
[assembly: AssemblyCulture("")]

// Setting ComVisible to false makes the types in this assembly not visible
// to COM components.  If you need to access a type in this assembly from
// COM, set the ComVisible attribute to true on that type.
[assembly: ComVisible(false)]

// The following GUID is for the ID of the typelib if this project is exposed to COM
[assembly: Guid("2fda4fb1-6855-4af5-a0a3-fbe861dcc734")]

// Version information for an assembly consists of the following four values:
//
//      Major Version
//      Minor Version
//      Build Number
//      Revision
//
// You can specify all the values or you can default the Build and Revision Numbers
// by using the '*' as shown below:
// [assembly: AssemblyVersion("1.0.*")]
[assembly: AssemblyVersion("1.0.0.0")]
[assembly: AssemblyFileVersion("1.0.0.0")]

// Allow moq to access internal constructors of entities
[assembly: InternalsVisibleTo("DynamicProxyGenAssembly2,PublicKey=0024000004800000940000000602000000240000525341310004000001000100c547cac37abd99c8db225ef2f6c8a3602f3b3606cc9891605d02baa56104f4cfc0734aa39b93bf7852f7d9266654753cc297e7d2edfe0bac1cdcf9f717241550e0a7b191195b7667bb4f64bcb8e2121380fd1d9d46ad2d92d2d15605093924cceaf74c4861eff62abf69b9291ed0a340e113be11e6a7d3113e92484cf7045cc7")]

Any ideas how this may be fixed?

[jdbriaris]

Using [assembly:InternalsVisibleTo("DynamicProxyGenAssembly2")] seems to work. Why does the version with the PublicKey as stated in the docs not work?

[stakx]

@jdbriaris, thank you for reporting this.

The quickstart guide contained an inaccuracy here. You only need to include the public key in the assembly name if your own assembly is strong-named. If it isn't, then you should not include the public key.

It seems that you are not strong-naming your project that uses Moq, so I believe you've already discovered the correct solution.

I've updated the quickstart guide accordingly.