kunit: Support for Parameterized Testing

Implementation of support for parameterized testing in KUnit. This
approach requires the creation of a test case using the
KUNIT_CASE_PARAM() macro that accepts a generator function as input.

This generator function should return the next parameter given the
previous parameter in parameterized tests. It also provides a macro to
generate common-case generators based on arrays. Generators may also
optionally provide a human-readable description of parameters, which is
displayed where available.

Note, currently the result of each parameter run is displayed in
diagnostic lines, and only the overall test case output summarizes
TAP-compliant success or failure of all parameter runs. In future, when
supported by kunit-tool, these can be turned into subsubtest outputs.

Signed-off-by: Arpitha Raghunandan <98.arpi@gmail.com>
Co-developed-by: Marco Elver <elver@google.com>
Signed-off-by: Marco Elver <elver@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Tested-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

1 files changed, 46 insertions, 13 deletions

diff --git a/lib/kunit/test.c b/lib/kunit/test.c
index 750704abe89a..ec9494e914ef 100644
--- a/lib/kunit/test.c
+++ b/lib/kunit/test.c
@@ -325,39 +325,72 @@ static void kunit_catch_run_case(void *data)
  * occur in a test case and reports them as failures.
  */
 static void kunit_run_case_catch_errors(struct kunit_suite *suite,
-					struct kunit_case *test_case)
+					struct kunit_case *test_case,
+					struct kunit *test)
 {
 	struct kunit_try_catch_context context;
 	struct kunit_try_catch *try_catch;
-	struct kunit test;
 
-	kunit_init_test(&test, test_case->name, test_case->log);
-	try_catch = &test.try_catch;
+	kunit_init_test(test, test_case->name, test_case->log);
+	try_catch = &test->try_catch;
 
 	kunit_try_catch_init(try_catch,
-			     &test,
+			     test,
 			     kunit_try_run_case,
 			     kunit_catch_run_case);
-	context.test = &test;
+	context.test = test;
 	context.suite = suite;
 	context.test_case = test_case;
 	kunit_try_catch_run(try_catch, &context);
 
-	test_case->success = test.success;
-
-	kunit_print_ok_not_ok(&test, true, test_case->success,
-			      kunit_test_case_num(suite, test_case),
-			      test_case->name);
+	test_case->success = test->success;
 }
 
 int kunit_run_tests(struct kunit_suite *suite)
 {
+	char param_desc[KUNIT_PARAM_DESC_SIZE];
 	struct kunit_case *test_case;
 
 	kunit_print_subtest_start(suite);
 
-	kunit_suite_for_each_test_case(suite, test_case)
-		kunit_run_case_catch_errors(suite, test_case);
+	kunit_suite_for_each_test_case(suite, test_case) {
+		struct kunit test = { .param_value = NULL, .param_index = 0 };
+		bool test_success = true;
+
+		if (test_case->generate_params) {
+			/* Get initial param. */
+			param_desc[0] = '\0';
+			test.param_value = test_case->generate_params(NULL, param_desc);
+		}
+
+		do {
+			kunit_run_case_catch_errors(suite, test_case, &test);
+			test_success &= test_case->success;
+
+			if (test_case->generate_params) {
+				if (param_desc[0] == '\0') {
+					snprintf(param_desc, sizeof(param_desc),
+						 "param-%d", test.param_index);
+				}
+
+				kunit_log(KERN_INFO, &test,
+					  KUNIT_SUBTEST_INDENT
+					  "# %s: %s %d - %s",
+					  test_case->name,
+					  kunit_status_to_string(test.success),
+					  test.param_index + 1, param_desc);
+
+				/* Get next param. */
+				param_desc[0] = '\0';
+				test.param_value = test_case->generate_params(test.param_value, param_desc);
+				test.param_index++;
+			}
+		} while (test.param_value);
+
+		kunit_print_ok_not_ok(&test, true, test_success,
+				      kunit_test_case_num(suite, test_case),
+				      test_case->name);
+	}
 
 	kunit_print_subtest_end(suite);