Commit fadb08e7c750 ("kunit: Support for Parameterized Testing")
introduced support but lacks documentation for how to use it.
This patch builds on commit 1f0e943df68a ("Documentation: kunit: provide
guidance for testing many inputs") to show a minimal example of the new
feature.
Signed-off-by: Daniel Latypov <dlatypov@xxxxxxxxxx>
---
Documentation/dev-tools/kunit/usage.rst | 57 +++++++++++++++++++++++++
1 file changed, 57 insertions(+)
diff --git a/Documentation/dev-tools/kunit/usage.rst b/Documentation/dev-tools/kunit/usage.rst
index d9fdc14f0677..650f99590df5 100644
--- a/Documentation/dev-tools/kunit/usage.rst
+++ b/Documentation/dev-tools/kunit/usage.rst
@@ -522,6 +522,63 @@ There's more boilerplate involved, but it can:
* E.g. if we wanted to also test ``sha256sum``, we could add a ``sha256``
field and reuse ``cases``.
+* be converted to a "parameterized test", see below.
+
+Parameterized Testing
+~~~~~~~~~~~~~~~~~~~~~
+
+The table-driven testing pattern is common enough that KUnit has special
+support for it.
+
+Reusing the same ``cases`` array from above, we can write the test as a
+"parameterized test" with the following.
+
+.. code-block:: c
+
+ // This is copy-pasted from above.
+ struct sha1_test_case {
+ const char *str;
+ const char *sha1;
+ };
+ struct sha1_test_case cases[] = {
+ {
+ .str = "hello world",
+ .sha1 = "2aae6c35c94fcfb415dbe95f408b9ce91ee846ed",
+ },
+ {
+ .str = "hello world!",
+ .sha1 = "430ce34d020724ed75a196dfc2ad67c77772d169",
+ },
+ };
+
+ // Need a helper function to generate a name for each test case.
+ static void case_to_desc(const struct sha1_test_case *t, char *desc)
+ {
+ strcpy(desc, t->str);
+ }
+ // Creates `sha1_gen_params()` to iterate over `cases`.
+ KUNIT_ARRAY_PARAM(sha1, cases, case_to_desc);
+
+ // Looks no different from a normal test.
+ static void sha1_test(struct kunit *test)
+ {
+ // This function can just contain the body of the for-loop.
+ // The former `cases[i]` is accessible under test->param_value.
+ char out[40];
+ struct sha1_test_case *test_param = (struct sha1_test_case *)(test->param_value);
+
+ sha1sum(test_param->str, out);
+ KUNIT_EXPECT_STREQ_MSG(test, (char *)out, test_param->sha1,
+ "sha1sum(%s)", test_param->str);
+ }
+
+ // Instead of KUNIT_CASE, we use KUNIT_CASE_PARAM and pass in the
+ // function declared by KUNIT_ARRAY_PARAM.
+ static struct kunit_case sha1_test_cases[] = {
+ KUNIT_CASE_PARAM(sha1_test, sha1_gen_params),
+ {}
+ };
+
.. _kunit-on-non-uml:
KUnit on non-UML architectures
base-commit: 5f6b99d0287de2c2d0b5e7abcb0092d553ad804a
--
2.29.2.684.gfbc64c5ab5-goog
