Unit Class Test Method will not run

I created a Test Class in SE24, and created one method with the following code:

private section.

  methods CREATE_ISTREAM_XSTRING_TEST
  for testing .
  methods SETUP .
  methods TEARDOWN .

METHOD create_istream_xstring_test

   CALL METHOD CL_AUNIT_ASSERT=>FAIL
       EXPORTING
         MSG    = 'Deliberate fail'
         LEVEL  = 2
*        QUIT   = METHOD
*        DETAIL =
        .
ENDMETHOD.

For some reason it won't hit this code and the status window informs me that

Unit tests processed successfully; 1 programs, 0 classes, 0 methods

When I run a unit test.

Why won't the method get executed when testing?