This internal utility function inspects the `test_pkg_data` structure to identify which testing framework is used in the package and returns the corresponding test path.
get_stf_test_path(test_pkg_data, testdir)A character string representing the path to the test directory, or `NULL` if no known test framework is found.
A named list containing logical flags such as `has_testthat`, `has_testit`, `has_tests_base`, etc.
A character string specifying the root directory where test folders are located.