in reply to Problem with orderly execution of test cases in .t file
What I always do is to create numbered test-files, and to put one relevant test in each file. (Like t/0100_basic_tests/0150_test_thing.t.) The files will be executed in sorted order, and directory traversal is also in sorted order.
Each test file is “executed,” so whatever it has inside each file will be carried out in sequence.