title: Mocking without using inerfaces
body: <p>Is there any way to use moq without definig interfaces??
  I had try to use with method that i am testing.</p>
  
  <pre><code>var real = new SubCoreClass();
  var mock = new Mock&lt;SubCoreClass&gt;();
  </code></pre>
  
  <p>But i got error in Setup:</p>
  
  <pre><code>mock.Setup(t =&gt; t.method(It.IsAny&lt;string&gt;(),It.IsAny&lt;string&gt;(),It.IsAny&lt;string&gt;()));
  </code></pre>
  
  <p>: Invalid setup on a non-virtual </p>