kunit: tool: Add (primitive) support for outputting JUnit XML

This is used by things like Jenkins and other CI systems, which can
pretty-print the test output and potentially provide test-level comparisons
between runs.

The implementation here is pretty basic: it only provides the raw results,
split into tests and test suites, and doesn't provide any overall metadata.
However, CI systems like Jenkins can ingest it and it is already useful.

Link: https://lore.kernel.org/r/20260606013827.240790-2-david@davidgow.net
Reviewed-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: David Gow <david@davidgow.net>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

3 files changed, 117 insertions, 4 deletions

diff --git a/tools/testing/kunit/kunit.py b/tools/testing/kunit/kunit.py
index 742f5c555666..ac3f7159e67f 100755
--- a/tools/testing/kunit/kunit.py
+++ b/tools/testing/kunit/kunit.py
@@ -21,6 +21,7 @@ from enum import Enum, auto
 from typing import Iterable, List, Optional, Sequence, Tuple
 
 import kunit_json
+import kunit_junit
 import kunit_kernel
 import kunit_parser
 from kunit_printer import stdout, null_printer
@@ -49,6 +50,7 @@ class KunitBuildRequest(KunitConfigRequest):
 class KunitParseRequest:
 	raw_output: Optional[str]
 	json: Optional[str]
+	junit: Optional[str]
 	summary: bool
 	failed: bool
 
@@ -268,6 +270,13 @@ def parse_tests(request: KunitParseRequest, metadata: kunit_json.Metadata, input
 			stdout.print_with_timestamp("Test results stored in %s" %
 				os.path.abspath(request.json))
 
+	if request.junit:
+		if request.junit == 'stdout':
+			kunit_junit.print_junit_result(test=test)
+		else:
+			kunit_junit.write_junit_result(test=test,filename=request.junit)
+			stdout.print_with_timestamp(f"Test results stored in {os.path.abspath(request.junit)}")
+
 	if test.status != kunit_parser.TestStatus.SUCCESS:
 		return KunitResult(KunitStatus.TEST_FAILURE, parse_time), test
 
@@ -309,6 +318,7 @@ def run_tests(linux: kunit_kernel.LinuxSourceTree,
 # So we hackily automatically rewrite --json => --json=stdout
 pseudo_bool_flag_defaults = {
 		'--json': 'stdout',
+		'--junit': 'stdout',
 		'--raw_output': 'kunit',
 }
 def massage_argv(argv: Sequence[str]) -> Sequence[str]:
@@ -459,6 +469,11 @@ def add_parse_opts(parser: argparse.ArgumentParser) -> None:
 			    help='Prints parsed test results as JSON to stdout or a file if '
 			    'a filename is specified. Does nothing if --raw_output is set.',
 			    type=str, const='stdout', default=None, metavar='FILE')
+	parser.add_argument('--junit',
+			    nargs='?',
+			    help='Prints parsed test results as JUnit XML to stdout or a file if '
+			    'a filename is specified. Does nothing if --raw_output is set.',
+			    type=str, const='stdout', default=None, metavar='FILE')
 	parser.add_argument('--summary',
 			    help='Prints only the summary line for parsed test results.'
 				'Does nothing if --raw_output is set.',
@@ -502,6 +517,7 @@ def run_handler(cli_args: argparse.Namespace) -> None:
 					jobs=cli_args.jobs,
 					raw_output=cli_args.raw_output,
 					json=cli_args.json,
+					junit=cli_args.junit,
 					summary=cli_args.summary,
 					failed=cli_args.failed,
 					timeout=cli_args.timeout,
@@ -552,6 +568,7 @@ def exec_handler(cli_args: argparse.Namespace) -> None:
 	exec_request = KunitExecRequest(raw_output=cli_args.raw_output,
 					build_dir=cli_args.build_dir,
 					json=cli_args.json,
+					junit=cli_args.junit,
 					summary=cli_args.summary,
 					failed=cli_args.failed,
 					timeout=cli_args.timeout,
@@ -580,7 +597,9 @@ def parse_handler(cli_args: argparse.Namespace) -> None:
 	# We know nothing about how the result was created!
 	metadata = kunit_json.Metadata()
 	request = KunitParseRequest(raw_output=cli_args.raw_output,
-					json=cli_args.json, summary=cli_args.summary,
+					json=cli_args.json,
+					junit=cli_args.junit,
+					summary=cli_args.summary,
 					failed=cli_args.failed)
 	result, _ = parse_tests(request, metadata, kunit_output)
 	if result.status != KunitStatus.SUCCESS:
diff --git a/tools/testing/kunit/kunit_junit.py b/tools/testing/kunit/kunit_junit.py
new file mode 100644
index 000000000000..3622070358e7
--- /dev/null
+++ b/tools/testing/kunit/kunit_junit.py
@@ -0,0 +1,61 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Generates JUnit XML files from KUnit test results
+#
+# Copyright (C) 2026, Google LLC and David Gow.
+
+from xml.sax.saxutils import quoteattr, XMLGenerator
+import xml.etree.ElementTree as ET
+from kunit_parser import Test, TestStatus
+from typing import Optional
+
+# Get a string representing a tes suite (including subtests) in JUnit XML
+def get_test_suite(test: Test, parent: Optional[ET.Element]) -> ET.Element:
+	suite_attrs = {
+		'name': test.name,
+		'tests': str(test.counts.total()),
+		'failures': str(test.counts.failed),
+		'skipped': str(test.counts.skipped),
+		'errors': str(test.counts.crashed + test.counts.errors),
+	}
+
+	if parent is not None:
+		test_suite_element = ET.SubElement(parent, 'testsuite', suite_attrs)
+	else:
+		test_suite_element = ET.Element('testsuite', suite_attrs)
+
+	for subtest in test.subtests:
+		if subtest.subtests:
+			get_test_suite(subtest, test_suite_element)
+			continue
+		test_case_element = ET.SubElement(test_suite_element, 'testcase', {'name': subtest.name})
+		if subtest.status == TestStatus.FAILURE:
+			ET.SubElement(test_case_element, 'failure', {}).text = 'Test Failed'
+		elif subtest.status == TestStatus.SKIPPED:
+			ET.SubElement(test_case_element, 'skipped', {}).text = subtest.skip_reason
+		elif subtest.status == TestStatus.TEST_CRASHED:
+			ET.SubElement(test_case_element, 'error', {}).text = 'Test Crashed'
+
+		if subtest.log:
+			ET.SubElement(test_case_element, 'system-out', {}).text = "\n".join(subtest.log)
+
+	return test_suite_element
+
+# Get a string for an entire XML file for the test structure starting at test
+def get_junit_result(test: Test) -> str:
+	root_element = get_test_suite(test, None)
+	ET.indent(root_element)
+	return ET.tostring(root_element, encoding="unicode", xml_declaration=True)
+
+# Print a JUnit result to stdout.
+def print_junit_result(test: Test) -> None:
+	root_element = get_test_suite(test, None)
+	ET.indent(root_element)
+	ET.dump(root_element)
+
+# Write an entire XML file for the test structure starting at test
+def write_junit_result(test: Test, filename: str) -> None:
+	root_element = get_test_suite(test, None)
+	ET.indent(root_element)
+	root_et = ET.ElementTree(root_element)
+	root_et.write(filename, encoding='utf-8', xml_declaration=True)
diff --git a/tools/testing/kunit/kunit_tool_test.py b/tools/testing/kunit/kunit_tool_test.py
index 5ebd551b5072..da88c3a1651d 100755
--- a/tools/testing/kunit/kunit_tool_test.py
+++ b/tools/testing/kunit/kunit_tool_test.py
@@ -24,6 +24,7 @@ import kunit_config
 import kunit_parser
 import kunit_kernel
 import kunit_json
+import kunit_junit
 import kunit
 from kunit_printer import stdout
 
@@ -693,6 +694,38 @@ class StrContains(str):
 	def __eq__(self, other):
 		return self in other
 
+class KUnitJUnitTest(unittest.TestCase):
+	def setUp(self):
+		self.print_mock = mock.patch('kunit_printer.Printer.print').start()
+		self.addCleanup(mock.patch.stopall)
+
+	def _junit_string(self, log_file):
+		with open(_test_data_path(log_file)) as file:
+			test_result = kunit_parser.parse_run_tests(file, stdout)
+			junit_string = kunit_junit.get_junit_result(
+					test=test_result)
+		print(junit_string)
+		return junit_string
+
+	def test_failed_test_junit(self):
+		result = self._junit_string('test_is_test_passed-failure.log')
+		self.assertTrue("<failure>" in result)
+
+	def test_skipped_test_junit(self):
+		result = self._junit_string('test_skip_tests.log')
+		self.assertTrue("<skipped>" in result)
+		self.assertTrue("skipped=\"1\"" in result)
+
+	def test_crashed_test_junit(self):
+		result = self._junit_string('test_kernel_panic_interrupt.log')
+		self.assertTrue("<error>" in result);
+
+	def test_no_tests_junit(self):
+		result = self._junit_string('test_is_test_passed-no_tests_run_with_header.log')
+		self.assertTrue("tests=\"0\"" in result)
+		self.assertFalse("testcase" in result)
+
+
 class KUnitMainTest(unittest.TestCase):
 	def setUp(self):
 		path = _test_data_path('test_is_test_passed-all_passed.log')
@@ -940,7 +973,7 @@ class KUnitMainTest(unittest.TestCase):
 		self.linux_source_mock.run_kernel.return_value = ['TAP version 14', 'init: random output'] + want
 
 		got = kunit._list_tests(self.linux_source_mock,
-				     kunit.KunitExecRequest(None, None, False, False, '.kunit', 300, 'suite*', '', None, None, 'suite', False, False, False))
+				     kunit.KunitExecRequest(None, None, None, False, False, '.kunit', 300, 'suite*', '', None, None, 'suite', False, False, False))
 		self.assertEqual(got, want)
 		# Should respect the user's filter glob when listing tests.
 		self.linux_source_mock.run_kernel.assert_called_once_with(
@@ -953,7 +986,7 @@ class KUnitMainTest(unittest.TestCase):
 
 		# Should respect the user's filter glob when listing tests.
 		mock_tests.assert_called_once_with(mock.ANY,
-				     kunit.KunitExecRequest(None, None, False, False, '.kunit', 300, 'suite*.test*', '', None, None, 'suite', False, False, False))
+				     kunit.KunitExecRequest(None, None, None, False, False, '.kunit', 300, 'suite*.test*', '', None, None, 'suite', False, False, False))
 		self.linux_source_mock.run_kernel.assert_has_calls([
 			mock.call(args=None, build_dir='.kunit', filter_glob='suite.test*', filter='', filter_action=None, timeout=300),
 			mock.call(args=None, build_dir='.kunit', filter_glob='suite2.test*', filter='', filter_action=None, timeout=300),
@@ -966,7 +999,7 @@ class KUnitMainTest(unittest.TestCase):
 
 		# Should respect the user's filter glob when listing tests.
 		mock_tests.assert_called_once_with(mock.ANY,
-				     kunit.KunitExecRequest(None, None, False, False, '.kunit', 300, 'suite*', '', None, None, 'test', False, False, False))
+				     kunit.KunitExecRequest(None, None, None, False, False, '.kunit', 300, 'suite*', '', None, None, 'test', False, False, False))
 		self.linux_source_mock.run_kernel.assert_has_calls([
 			mock.call(args=None, build_dir='.kunit', filter_glob='suite.test1', filter='', filter_action=None, timeout=300),
 			mock.call(args=None, build_dir='.kunit', filter_glob='suite.test2', filter='', filter_action=None, timeout=300),