On Thu, May 18, 2023 at 04:38:46PM +0800, David Gow wrote:
+Registering Cleanup Actions +---------------------------
+If you need to perform some cleanup beyond simple use of ``kunit_kzalloc``, +you can register a cusom "deferred action", which is a cleanup function +run when the test exits (whether cleanly, or via a failed assertion).
+Actions are simple functions with no return value, and a single ``void*`` +context argument, and forfil the same role as "cleanup" functions in Python
"... fulfill the same role ..."?
+and Go tests, "defer" statements in languages which support them, and +(in some cases) destructors in RAII languages.
+These are very useful for unregistering things from global lists, closing +files or other resources, or freeing resources.
+For example:
+.. code-block:: C
- static void cleanup_device(void *ctx)
- {
struct device *dev = (struct device *)ctx;device_unregister(dev);- }
- void example_device_test(struct kunit *test)
- {
struct my_device dev;device_register(&dev);kunit_add_action(test, &cleanup_device, &dev);- }
+Note that, for functions like device_unregister which only accept a single +pointer-sized argument, it's possible to directly cast that function to +a ``kunit_action_t`` rather than writing a wrapper function, for example:
+.. code-block:: C
- kunit_add_action(test, (kunit_action_t *)&device_unregister, &dev);
+``kunit_add_action`` can fail if, for example, the system is out of memory. +You can use ``kunit_add_action_or_reset`` instead which runs the action +immediately if it cannot be deferred.
+If you need more control over when the cleanup function is called, you +can trigger it early using ``kunit_release_action``, or cancel it entirely +with ``kunit_remove_action``.
Testing Static Functions
The rest is LGTM.