Last Updated: 06 Nov 2013 10:30 by Ovidiu

Since I upgraded my JustMock I was unable to debug ASP.NET projects. I accidentally found a resolution to the problem here:

"If you are using Telerik JustMock as a mocking framework and have recently updated it to the 2013 Q3 version, it causes this exact problem. I was able to resolve this issue by uninstalling the mocking framework and installing the 2013 Q2 version."

So I uninstalled JustMock and everything came to normal.

Last Updated: 16 Jan 2019 08:51 by ADMIN
Created by: Michael
Comments: 4
Type: Bug Report
Creating a share link with Visual Studio Live Share does not work if you have the JustMock profiler enabled. We specifically have to disable the JustMock profiler in order for VS Live Share to create sharing links. This has been reproduced by several different members of our team.

Could this please be looked into? Thanks!
Last Updated: 18 Jun 2019 08:43 by ADMIN
There is a different behaviour when mocking the same method using the following two Arrange overrides:

public static FuncExpectation<TResult> Arrange<TResult>(Expression<Func<TResult>> expression);
public static FuncExpectation<TResult> Arrange<T, TResult>(T obj, Func<T, TResult> func);

Repro project attached. Steps to reproduce:
1. Open attached solution
2. In Tests.cs, run JustMockArrangeQueryableTest - it passes
3. Run JustMockArrangeQueryableTest2 - it fails with a invalid cast exception on the Residents collection.
Last Updated: 18 Jun 2019 08:37 by ADMIN
The integration between JustMock and dotCover stopped working with R2 2019. The result when code coverage is started is that all tests remain in pending state and does not finish while the CPU is idle.
Last Updated: 20 May 2019 09:32 by ADMIN
Mocking an async calls alse triggers hidden mocking of the return type. Depending of the type it might cause unexpected behavior or exception.
Last Updated: 20 May 2019 09:26 by ADMIN
A class property get wrongly mocked when used as parameter for arranging other class methods. The following sample demonstrates the scenario:

class Foo
	public string Prop{ get; set; }

	public void Bar(string val)

public void Sample()
	var sut = Mock.Create<Foo>(Behavior.CallOriginal);

	Mock.Arrange(() => sut.Bar(sut.Prop)).DoNothing();
Last Updated: 15 Jan 2020 09:58 by ADMIN
The JustMock tests are failing when the "Test platform version" option in the JustMock VSTest v.2 task is set to value "Installed by Tools Installer".
Last Updated: 24 Sep 2019 10:06 by ADMIN
The execution of JustMock tests stoped working in Visual Studio. The exact version is 16.2.1. The error message is: "The profiler must be enabled to mock, arrange or execute the specified target."
Last Updated: 04 Nov 2013 16:02 by ADMIN
using NUnit.Framework;
using Telerik.JustMock;

namespace Example
    public class MyClass
        public MyClass(int a = 5) { }

    public class TestMyClass
        public void test_MyClass()

Telerik.JustMock.MockException : Can not instantiate proxy of class: Example.MyClass.
Could not find a parameterless constructor.
   at Telerik.JustMock.Core.MocksRepository.Create(Type type, MockCreationSettings settings)
   at Telerik.JustMock.MockBuilder.Create(MocksRepository repository, Type type, Object[] constructorArgs, Nullable`1 behavior, Type[] additionalMockedInterfaces, Nullable`1 mockConstructorCall, IEnumerable`1 additionalProxyTypeAttributes, List`1 supplementaryBehaviors, List`1 fallbackBehaviors, List`1 mixins)
   at Telerik.JustMock.Mock.<>c__DisplayClass5b`1.<Create>b__5a()
   at Telerik.JustMock.Core.ProfilerInterceptor.GuardInternal[T](Func`1 guardedAction)
   at Telerik.JustMock.Mock.Create[T](Behavior behavior, Object[] args)
   at Example.TestMyClass.test_MyClass() in c:\users\micah\Documents\Source\Test\Test\Class1.cs:line 17#0

This appears to be related to the recent fix for "Improve exception message for Mock.Create".  Without Behavior.CallOriginal it works.  Supplying a parameter also works.
Last Updated: 04 Nov 2013 15:55 by ADMIN
Created by: Thomas
Comments: 3
Type: Bug Report
I need to be able to mock in Winrt. If that is already possible, then you need to spell out in example form how that is done.
Last Updated: 27 Aug 2013 06:39 by Omer
Created by: Omer
Comments: 0
Type: Bug Report
Hi there, I'm a developer on OzCode, a Visual Studio extension ( ).

We've received some complaints from customers that OzCode is incompatible with JustCode. I installed JustMock, and saw that when Visual Studio starts up, JustMock it seems to be causing a crash in a child process that OzCode spawns off of devenv.exe, which is called 'BugAidMetadataLoader.exe':

The exception in this process is:

Additional information: Could not load type 'Telerik.JustMock.Profiler' from assembly 'mscorlib, Version=, Culture=neutral, PublicKeyToken=b77a5c561934e089'.

I would guess that JustMock is unintentionally causing the process to be loaded with a CLR Profiler attached and injecting code into it, and the injected code causes the crash.

Could you please provide some advice on how to avoid this, or possibly provide a fix?

Thank you very much,
 - Omer Raviv, OzCode
Last Updated: 17 May 2013 12:44 by Jakub
When I try to invoke method from intercepted class in multi-thread test sometimes I get following exception:
Destination array was not long enough. Check destIndex and length, and the array's lower bounds.
   at System.Array.Copy(Array sourceArray, Int32 sourceIndex, Array destinationArray, Int32 destinationIndex, Int32 length, Boolean reliable)
   at System.Array.Copy(Array sourceArray, Int32 sourceIndex, Array destinationArray, Int32 destinationIndex, Int32 length)
   at System.Collections.Generic.List`1.CopyTo(T[] array, Int32 arrayIndex)
   at System.Collections.Generic.List`1..ctor(IEnumerable`1 collection)
   at System.Linq.Enumerable.ToList(IEnumerable`1 source)
   at Telerik.JustMock.Weaver.ContainerContext.InstanceIdentifier.GetUniqueId(Object target)
   at Telerik.JustMock.Weaver.ContainerContext.Get(Type targetType, MethodBase methodInfo, Object target)
   at Telerik.JustMock.Weaver.ContainerContext.Get(MethodBase methodBase, Object target)
   at Telerik.JustMock.Weaver.Interceptors.WeaverInterceptor.OnInvocation(IInvocation invocation)
   at Telerik.JustMock.Weaver.Interceptors.WeaverInterceptor.Telerik.JustMock.Weaver.Interceptors.Abstraction.IWeaverInterceptor.Intercept(IInvocation invocation)
   at TestClass_Interceptor_620e5e80fe0c4d738f7ef291ea50ea2a.Intercept(TestClass, ref Boolean)
   at ExceptionExample.TestClass.ExecuteSomething() in Test.cs: line 174
   at ExceptionExample.RunMethod() in Test.cs: line 199
   at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
   at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
   at System.Threading.ThreadHelper.ThreadStart()

Sample class that generates exception:

public class ExceptionExample
	static ExceptionExample()

	public class TestClass
		public void ExecuteSomething()
			int y = 0;
			for (int i = 0; i < 100; i++)
				y += i;

	public void MethodName()
		List<Thread> l = new List<Thread>();

		for (int i = 0; i < 6; i++)
			Thread t = new Thread(RunMethod);

		l.ForEach(th => th.Join());

	private void RunMethod()
		for (int i = 0; i < 10000; i++)
			TestClass tc1 = new TestClass();
Last Updated: 17 May 2013 12:23 by David
I'm getting this argument exception:
System.ArgumentException : The type or method has 3 generic parameter(s), but 2 generic argument(s) were provided. A generic argument must be provided for each generic parameter.
   at System.RuntimeType.SanityCheckGenericArguments(RuntimeType[] genericArguments, RuntimeType[] genericParamters)
   at System.Reflection.RuntimeMethodInfo.MakeGenericMethod(Type[] methodInstantiation)
   at .š.(Type ‹, MethodBase „†, BindingFlags )
   at .š.(Type ‚, MethodBase „†)
   at ”.“.Create(Object š, MethodInfo ›, Boolean ’)
   at ..(˜ )
   at ..(Expression`1 )
   at Telerik.JustMock.Mock..Ž( )
   at ..—[,—]( , Func`2 )
   at Telerik.JustMock.Mock.Arrange[TResult](Expression`1 expression)

Heres an example of a failing test:

        public void GenericTestCanMockTwoGenericMethods()
            var mocked = Mock.Create<GenericTest>();
            IEnumerable<EVENT_CODE> n = null;
            Mock.Arrange(() => mocked.Query<EVENT_CODE, ALARM_CODE>(Arg.AnyString, Arg.IsAny<object>())).Returns(n).MustBeCalled();

        public interface GenericTest
            IEnumerable<T1> Query<T1, T2>(string arg1, params object[] args);

            IEnumerable<T1> Query<T1, T2, T3>(string arg1, params object[] args);
Last Updated: 22 Nov 2012 15:00 by Philip Japikse
If I have a constructor like this: public Foo(IAccount fromAccount, IAccount toAccount) { //code }, I need to be able to distinguish between the two accounts when automocking.
container.Arrange<IAccount>() won't work.  Perhaps container.Arrange<IAccount>[0] would. 
Last Updated: 12 Sep 2018 14:04 by ADMIN
MbUnitContextResolver gets wrongly initialized because of the weak check based on Gallio.Framework.Assertions.AssertionException type presence in the current app domain. Needs to be improved with some additional type check from mbunit assembly, MbUnit.Framework.TestFixtureAttribute for example.
Last Updated: 22 Jun 2018 07:48 by Jeremy
Created by: Michele
Comments: 3
Type: Bug Report
In Visual Studio 2015 Pro justmock generates this error error MSB6006: "vbc.exe" To function properly you need to uninstall VS2015 justmock.

Last Updated: 24 Nov 2015 08:37 by Simo
I have installed the trial version of JustMock to evaluate it. I have been trying to mock the static calls of Azure RoleEnvironment class, but the SetupStatic does not work. It seems to be calling the original method. Please see my simple test below:

public void VerifyRoleEnvironment()
       bool expected = true;
       Mock.SetupStatic(typeof(RoleEnvironment), StaticConstructor.Mocked);
       Mock.Arrange(() => RoleEnvironment.IsAvailable).Returns(true);
       Assert.AreEqual(expected, RoleEnvironment.IsAvailable);
Last Updated: 10 Jan 2014 09:04 by ADMIN
1. Load the attached project in Visual Studio 2013.
2. Update the NuGet packages (NUnit).
3. Update the reference to JustMock to point to the correct path to a retail version of Telerik.JustMock.dll.
4. Run tests in NUnit runner (or any other runner that will run them in the same process/sequentially.
5. --> Notice that the first TestCase will pass, the second will fail.
6. Run the two test cases separately.
7. --> Notice that they both pass.
8. Remove the reference to Telerik.JustMock.dll.
9. Use NuGet to get the latest JustMock Lite.
10. Run the tests again.
11. --> Notice that they both pass.

This appears to be a bug with JustMock (retail) 2013.3.1119.2.  The bug does not reproduce when using JustMock Lite from NuGet.

If you drop into a debugger and step through both tests in a row you see the following behavior:
1. When the first test is started (after SetUp has been called) FlagA is correctly set to true and FlagB is defaulted to false.
2. When you step over the Mock.Arrange, FlagA is still true and FlagB is set to the value of input (order of running tests doesn't appear to matter, second always fails).
3. When the second test starts (after SetUp has been called again) Flag A is correctly set to true and FlagB is defaulted to false.
4. When you step over the Mock.Arrange, FlagB is set to the value of input but FlagA has been reverted to default!

If you add several other properties to the interface they will all be reset to default (no matter how many you arrange) when the second test executes the Mock.Arrange.

This bug reproduces without the JustMock profiler attached, and also with the profiler attached.

The version of JustMock Lite that was tested against is 2014.1.1217.4.  When I run the Telerik Control Panel I am not prompted to update my version of JustMock beyond 2013.3.1119.2 (perhaps this bug is already fixed and I just need to figure out how to upgrade).
Last Updated: 18 Jun 2019 10:06 by ADMIN

Values from already mocked methods are not taken into account when initializing a static constructor from the Telerik.JustMock.PrivateAccessor class.

Here is an example: PrivateAccessor.ForType(typeof(Foo)).SetField("someStringField", "stringvalue");

A workaround is to call the: Mock.Intercept(typeof(Foo)); before calling the PrivateAccessor.

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