kunit: improve KTAP compliance of KUnit test output

Change KUnit test output to better comply with KTAP v1 specifications
found here: https://kernel.org/doc/html/latest/dev-tools/ktap.html.
1) Use "KTAP version 1" instead of "TAP version 14" as test output header
2) Remove '-' between test number and test name on test result lines
2) Add KTAP version lines to each subtest header as well

Note that the new KUnit output still includes the “# Subtest” line now
located after the KTAP version line. This does not completely match the
KTAP v1 spec but since it is classified as a diagnostic line, it is not
expected to be disruptive or break any existing parsers. This
“# Subtest” line comes from the TAP 14 spec
(https://testanything.org/tap-version-14-specification.html) and it is
used to define the test name before the results.

Original output:

 TAP version 14
 1..1
   # Subtest: kunit-test-suite
   1..3
   ok 1 - kunit_test_1
   ok 2 - kunit_test_2
   ok 3 - kunit_test_3
 # kunit-test-suite: pass:3 fail:0 skip:0 total:3
 # Totals: pass:3 fail:0 skip:0 total:3
 ok 1 - kunit-test-suite

New output:

 KTAP version 1
 1..1
   KTAP version 1
   # Subtest: kunit-test-suite
   1..3
   ok 1 kunit_test_1
   ok 2 kunit_test_2
   ok 3 kunit_test_3
 # kunit-test-suite: pass:3 fail:0 skip:0 total:3
 # Totals: pass:3 fail:0 skip:0 total:3
 ok 1 kunit-test-suite
Signed-off-by: Rae Moar <rmoar@google.com>
Reviewed-by: Daniel Latypov <dlatypov@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Tested-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

lib/kunit/debugfs.c

@@ -63,7 +63,7 @@ static int debugfs_print_results(struct seq_file *seq, void *v)
 	kunit_suite_for_each_test_case(suite, test_case)
 		debugfs_print_result(seq, suite, test_case);
 
-	seq_printf(seq, "%s %d - %s\n",
+	seq_printf(seq, "%s %d %s\n",
 		   kunit_status_to_ok_not_ok(success), 1, suite->name);
 	return 0;
 }

lib/kunit/executor.c

@@ -166,7 +166,7 @@ static void kunit_exec_run_tests(struct suite_set *suite_set)
 {
 	size_t num_suites = suite_set->end - suite_set->start;
 
-	pr_info("TAP version 14\n");
+	pr_info("KTAP version 1\n");
 	pr_info("1..%zu\n", num_suites);
 
 	__kunit_test_suites_init(suite_set->start, num_suites);
@@ -177,8 +177,8 @@ static void kunit_exec_list_tests(struct suite_set *suite_set)
 	struct kunit_suite * const *suites;
 	struct kunit_case *test_case;
 
-	/* Hack: print a tap header so kunit.py can find the start of KUnit output. */
-	pr_info("TAP version 14\n");
+	/* Hack: print a ktap header so kunit.py can find the start of KUnit output. */
+	pr_info("KTAP version 1\n");
 
 	for (suites = suite_set->start; suites < suite_set->end; suites++)
 		kunit_suite_for_each_test_case((*suites), test_case) {

lib/kunit/test.c

@@ -151,6 +151,7 @@ EXPORT_SYMBOL_GPL(kunit_suite_num_test_cases);
 
 static void kunit_print_suite_start(struct kunit_suite *suite)
 {
+	kunit_log(KERN_INFO, suite, KUNIT_SUBTEST_INDENT "KTAP version 1\n");
 	kunit_log(KERN_INFO, suite, KUNIT_SUBTEST_INDENT "# Subtest: %s",
 		  suite->name);
 	kunit_log(KERN_INFO, suite, KUNIT_SUBTEST_INDENT "1..%zd",
@@ -177,13 +178,13 @@ static void kunit_print_ok_not_ok(void *test_or_suite,
 	 * representation.
 	 */
 	if (suite)
-		pr_info("%s %zd - %s%s%s\n",
+		pr_info("%s %zd %s%s%s\n",
 			kunit_status_to_ok_not_ok(status),
 			test_number, description, directive_header,
 			(status == KUNIT_SKIPPED) ? directive : "");
 	else
 		kunit_log(KERN_INFO, test,
-			  KUNIT_SUBTEST_INDENT "%s %zd - %s%s%s",
+			  KUNIT_SUBTEST_INDENT "%s %zd %s%s%s",
 			  kunit_status_to_ok_not_ok(status),
 			  test_number, description, directive_header,
 			  (status == KUNIT_SKIPPED) ? directive : "");
@@ -544,6 +545,8 @@ int kunit_run_tests(struct kunit_suite *suite)
 			/* Get initial param. */
 			param_desc[0] = '\0';
 			test.param_value = test_case->generate_params(NULL, param_desc);
+			kunit_log(KERN_INFO, &test, KUNIT_SUBTEST_INDENT KUNIT_SUBTEST_INDENT
+				  "KTAP version 1\n");
 			kunit_log(KERN_INFO, &test, KUNIT_SUBTEST_INDENT KUNIT_SUBTEST_INDENT
 				  "# Subtest: %s", test_case->name);
 
@@ -557,7 +560,7 @@ int kunit_run_tests(struct kunit_suite *suite)
 
 				kunit_log(KERN_INFO, &test,
 					  KUNIT_SUBTEST_INDENT KUNIT_SUBTEST_INDENT
-					  "%s %d - %s",
+					  "%s %d %s",
 					  kunit_status_to_ok_not_ok(test.status),
 					  test.param_index + 1, param_desc);