      suite.Add(new OneTestCase());
        suite.Add(new Assemblies.AssemblyTests());
        suite.Add(new AssertionTest());
        return suite;
      }
    }
  }
}
</pre>

</div>

<p>This approach has a serious problem: it requires a reference to the nunit.core assembly,
	which is not normally referenced by user tests. This means that the tests
	cannot be ported across versions of NUnit without recompilation. In some cases,
	introducing more than one version of the core assembly can prevent NUnit
	from