Bug where a fake loses its fakeness

[TestClass, Isolated]
public class Tests
{
   public class A
   {
      public A()
      {
         B b2 = new B();
      }
   }

   public class B
   {
      public void BMethod()
      {
      }
   }

   [TestMethod]
   public void Test()
   {
      B b1 = Isolate.Fake.Instance<B>();
      Isolate.Fake.Instance<A>(Members.CallOriginal, ConstructorWillBe.Called);
      Isolate.Verify.WasCalledWithExactArguments(() => b1.BMethod());
   }
}