kunit: tool: print summary of failed tests if a few failed out of a lot

E.g. all the hw_breakpoint tests are failing right now.
So if I run `kunit.py run --altests --arch=x86_64`, then I see
> Testing complete. Ran 408 tests: passed: 392, failed: 9, skipped: 7

Seeing which 9 tests failed out of the hundreds is annoying.
If my terminal doesn't have scrollback support, I have to resort to
looking at `.kunit/test.log` for the `not ok` lines.

Teach kunit.py to print a summarized list of failures if the # of tests
reachs an arbitrary threshold (>=100 tests).

To try and keep the output from being too long/noisy, this new logic
a) just reports "parent_test failed" if every child test failed
b) won't print anything if there are >10 failures (also arbitrary).

With this patch, we get an extra line of output showing:
> Testing complete. Ran 408 tests: passed: 392, failed: 9, skipped: 7
> Failures: hw_breakpoint

This also works with parameterized tests, e.g. if I add a fake failure
> Failures: kcsan.test_atomic_builtins_missing_barrier.threads=6

Note: we didn't have enough tests for this to be a problem before.
But with commit 980ac3ad0512 ("kunit: tool: rename all_test_uml.config,
use it for --alltests"), --alltests works and thus running >100 tests
will probably become more common.

Signed-off-by: Daniel Latypov <dlatypov@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

1 files changed, 22 insertions, 0 deletions

diff --git a/tools/testing/kunit/kunit_tool_test.py b/tools/testing/kunit/kunit_tool_test.py
index a6e53945656e..7dcd67003b23 100755
--- a/tools/testing/kunit/kunit_tool_test.py
+++ b/tools/testing/kunit/kunit_tool_test.py
@@ -312,6 +312,28 @@ class KUnitParserTest(unittest.TestCase):
 				result.status)
 			self.assertEqual('kunit-resource-test', result.subtests[0].name)
 
+	def test_summarize_failures(self):
+		output = """
+		KTAP version 1
+		1..2
+			# Subtest: all_failed_suite
+			1..2
+			not ok 1 - test1
+			not ok 2 - test2
+		not ok 1 - all_failed_suite
+			# Subtest: some_failed_suite
+			1..2
+			ok 1 - test1
+			not ok 2 - test2
+		not ok 1 - some_failed_suite
+		"""
+		result = kunit_parser.parse_run_tests(output.splitlines())
+		self.assertEqual(kunit_parser.TestStatus.FAILURE, result.status)
+
+		self.assertEqual(kunit_parser._summarize_failed_tests(result),
+			'Failures: all_failed_suite, some_failed_suite.test2')
+
+
 def line_stream_from_strs(strs: Iterable[str]) -> kunit_parser.LineStream:
 	return kunit_parser.LineStream(enumerate(strs, start=1))