title: NSubstitute - mock throwing an exception in method returning void
body: <p>Using NSubstitute, how do you mock an exception being thrown in a method returning void?</p>
  
  <p>Let's say our method signature looks something like this:</p>
  
  <pre><code>    void Add();
  </code></pre>
  
  <p>Here's how NSubstitute docs say to mock throwing exceptions for void return types. But this doesn't compile :(</p>
  
  <pre><code>    myService
          .When(x =&gt; x.Add(-2, -2))
          .Do(x =&gt; { throw new Exception(); });
  </code></pre>
  
  <p>So how do you accomplish this?</p>