
  The above points should make it clear that it's preferable to split <a class="link" href="../user-guide.html#test-module.def">test module
  </a> into smaller units. These units are test cases. A test case has to be constructed based on some kind of
  function and registered in a test tree, so that the test runner knows how to invoke it. There are different
  possible designs for the test case construction problem: inheritance from the predefined base class, specifically
  named member function and so on.