Re: [PATCH v3 0/2] kunit: add macro to allow conditionally exposing static symbols to tests

[John Johansen]

On 12/6/22 17:40, Rae Moar wrote:
> Currently in order to test a static function, tests must be included in the
> same translation unit as the function. However, this can cause issues with
> including implementation and test code in the same file. As an alternative,
> the first patch in this series creates a macro that will set a function to
> be static or not depending on whether CONFIG_KUNIT is enabled. This allows
> the function to be visible during testing and static otherwise.
>
> As an example, the current status quo to test static functions is:
>
> === test.c ===
>
> static void test_case(struct kunit *test)
> {
>    KUNIT_EXPECT_EQ(test, my_func_to_test(), 2);
> }
>
> Then the tests are included in the implementation file as a workaround to
> the issue of testing static functions:
>
> === implementation.c ===
>
> static int my_func_to_test() {...}
> ...
> #include "test.c"
>
> Instead, the function could be defined with this new macro:
>
> === implementation.c ===
>
> VISIBLE_IF_KUNIT int my_func_to_test() {...}
>
> The first patch also creates a macro that will export a symbol into a kunit
> testing namespace only if CONFIG_KUNIT is enabled. This follows the logic
> above and allows symbols to be conditionally exported based on the testing
> status.
>
> The second patch in the series updates the policy_unpack test in AppArmor
> to show an example of how to use both of these macros in order to address
> the issue of testing static functions. Additionally, the patch allows the
> policy_unpack test to be built as a module.
>
> Changes since v2:
>   - Add mention of namespacing symbols to the commit message of the
>     second patch.
>   - Change module name in the second patch from policy_unpack_test to
>     apparmor_policy_unpack_test.
>
> Changes since v1:
>   - Changed the namespace of exported symbols for the apparmor
>     policy_unpack_test by adding the aa_ prefix.
>   - Separated the documentation comments for macros in
>     include/kunit/visibility.h.
>   - Changed copyright date and author for include/kunit/visibility.h.
>
> Rae Moar (2):
>    kunit: add macro to allow conditionally exposing static symbols to
>      tests
>    apparmor: test: make static symbols visible during kunit testing
>
>   include/kunit/visibility.h                |  33 +++
>   security/apparmor/Kconfig                 |   4 +-
>   security/apparmor/Makefile                |   3 +
>   security/apparmor/include/policy_unpack.h |  50 +++++
>   security/apparmor/policy_unpack.c         | 238 ++++++++++------------
>   security/apparmor/policy_unpack_test.c    |  69 ++++---
>   6 files changed, 229 insertions(+), 168 deletions(-)
>   create mode 100644 include/kunit/visibility.h
>
>
> base-commit: 0f08f3e2a0186dfb8e33cb46105228eb18448a0e

thanks Rae,

looks good to me, David unless you tell me otherwise I assume this is
still going in via the kselftest/kunit tree.