The tester manual overview refers to all other sections:
Similarly, $FILESPEC will fill in $TESTDIR for the current $FILENAME .
Also, $TESTSPEC will fill in $TESTDIR for the current $TESTNAME .
The first test run will create a database of test descriptions and each test is incremented sequentially. All new tests will be added to the database sequentially. This allows tests to be run and then changed with little side affects.
Note that if a test description changes, it is a new test to the database. So some tests may over time be orphaned.