Re: [PATCH] kunit: tool: Fix error messages for cases of no tests and wrong TAP header

[Daniel Latypov <dlatypov@google.com>]

On Wed, Jun 30, 2021 at 4:40 PM Rae Moar <rmoar@google.com> wrote:
>
> This patch addresses misleading error messages reported by kunit_tool in
> two cases. First, in the case of TAP output having an incorrect header
> format or missing a header, the parser used to output an error message of
> 'no tests run!'. Now the parser outputs an error message of 'could not
> parse test results!'.
>
> As an example:
>
> Before:
> $ ./tools/testing/kunit/kunit.py parse /dev/null
> [ERROR] no tests run!
> ...
>
> After:
> $ ./tools/testing/kunit/kunit.py parse /dev/null
> [ERROR] could not parse test results!
> ...
>
> Second, in the case of TAP output with the correct header but no
> tests, the parser used to output an error message of 'could not parse
> test results!'. Now the parser outputs an error message of 'no tests
> run!'.
>
> As an example:
>
> Before:
> $ echo -e 'TAP version 14\n1..0' | ./tools/testing/kunit/kunit.py parse
> [ERROR] could not parse test results!
>
> After:
> $ echo -e 'TAP version 14\n1..0' | ./tools/testing/kunit/kunit.py parse
> [ERROR] no tests run!
>
> Additionally, this patch also corrects the tests in kunit_tool_test.py
> and adds a test to check the error in the case of TAP output with the
> correct header but no tests (the log for this test was simplified from
> the first version of this patch).

Just as a note: usually people will mention changes between versions
of a patch series just above the diffstat.
Picking a random example from linux-kselftest:
https://lore.kernel.org/linux-kselftest/20210630081202.4423-7-yangbo.lu@nxp.com/

Note the extra "---" above those change notes, just like above the diffstat.

>
> Signed-off-by: Rae Moar <rmoar@google.com>

Reviewed-by: Daniel Latypov <dlatypov@google.com>

Thanks! Looks good to me.

Just a note to others, this is a v2 of
https://lore.kernel.org/linux-kselftest/20210629223541.1512296-1-rmoar@google.com/

> ---
>  tools/testing/kunit/kunit_parser.py              |  6 ++++--
>  tools/testing/kunit/kunit_tool_test.py           | 16 +++++++++++++---
>  ...st_is_test_passed-no_tests_run_no_header.log} |  0
>  ...t_is_test_passed-no_tests_run_with_header.log |  2 ++
>  4 files changed, 19 insertions(+), 5 deletions(-)
>  rename tools/testing/kunit/test_data/{test_is_test_passed-no_tests_run.log => test_is_test_passed-no_tests_run_no_header.log} (100%)
>  create mode 100644 tools/testing/kunit/test_data/test_is_test_passed-no_tests_run_with_header.log
>
> diff --git a/tools/testing/kunit/kunit_parser.py b/tools/testing/kunit/kunit_parser.py
> index c3c524b79db8..b88db3f51dc5 100644
> --- a/tools/testing/kunit/kunit_parser.py
> +++ b/tools/testing/kunit/kunit_parser.py
> @@ -338,9 +338,11 @@ def bubble_up_suite_errors(test_suites: Iterable[TestSuite]) -> TestStatus:
>  def parse_test_result(lines: LineStream) -> TestResult:
>         consume_non_diagnostic(lines)
>         if not lines or not parse_tap_header(lines):
> -               return TestResult(TestStatus.NO_TESTS, [], lines)
> +               return TestResult(TestStatus.FAILURE_TO_PARSE_TESTS, [], lines)
>         expected_test_suite_num = parse_test_plan(lines)
> -       if not expected_test_suite_num:
> +       if expected_test_suite_num == 0:
> +               return TestResult(TestStatus.NO_TESTS, [], lines)
> +       elif expected_test_suite_num is None:
>                 return TestResult(TestStatus.FAILURE_TO_PARSE_TESTS, [], lines)
>         test_suites = []
>         for i in range(1, expected_test_suite_num + 1):
> diff --git a/tools/testing/kunit/kunit_tool_test.py b/tools/testing/kunit/kunit_tool_test.py
> index bdae0e5f6197..75045aa0f8a1 100755
> --- a/tools/testing/kunit/kunit_tool_test.py
> +++ b/tools/testing/kunit/kunit_tool_test.py
> @@ -157,8 +157,18 @@ class KUnitParserTest(unittest.TestCase):
>                         kunit_parser.TestStatus.FAILURE,
>                         result.status)
>
> +       def test_no_header(self):
> +               empty_log = test_data_path('test_is_test_passed-no_tests_run_no_header.log')
> +               with open(empty_log) as file:
> +                       result = kunit_parser.parse_run_tests(
> +                               kunit_parser.extract_tap_lines(file.readlines()))
> +               self.assertEqual(0, len(result.suites))
> +               self.assertEqual(
> +                       kunit_parser.TestStatus.FAILURE_TO_PARSE_TESTS,
> +                       result.status)
> +
>         def test_no_tests(self):
> -               empty_log = test_data_path('test_is_test_passed-no_tests_run.log')
> +               empty_log = test_data_path('test_is_test_passed-no_tests_run_with_header.log')
>                 with open(empty_log) as file:
>                         result = kunit_parser.parse_run_tests(
>                                 kunit_parser.extract_tap_lines(file.readlines()))
> @@ -173,7 +183,7 @@ class KUnitParserTest(unittest.TestCase):
>                 with open(crash_log) as file:
>                         result = kunit_parser.parse_run_tests(
>                                 kunit_parser.extract_tap_lines(file.readlines()))
> -               print_mock.assert_any_call(StrContains('no tests run!'))
> +               print_mock.assert_any_call(StrContains('could not parse test results!'))
>                 print_mock.stop()
>                 file.close()
>
> @@ -309,7 +319,7 @@ class KUnitJsonTest(unittest.TestCase):
>                         result["sub_groups"][1]["test_cases"][0])
>
>         def test_no_tests_json(self):
> -               result = self._json_for('test_is_test_passed-no_tests_run.log')
> +               result = self._json_for('test_is_test_passed-no_tests_run_with_header.log')
>                 self.assertEqual(0, len(result['sub_groups']))
>
>  class StrContains(str):
> diff --git a/tools/testing/kunit/test_data/test_is_test_passed-no_tests_run.log b/tools/testing/kunit/test_data/test_is_test_passed-no_tests_run_no_header.log
> similarity index 100%
> rename from tools/testing/kunit/test_data/test_is_test_passed-no_tests_run.log
> rename to tools/testing/kunit/test_data/test_is_test_passed-no_tests_run_no_header.log
> diff --git a/tools/testing/kunit/test_data/test_is_test_passed-no_tests_run_with_header.log b/tools/testing/kunit/test_data/test_is_test_passed-no_tests_run_with_header.log
> new file mode 100644
> index 000000000000..5f48ee659d40
> --- /dev/null
> +++ b/tools/testing/kunit/test_data/test_is_test_passed-no_tests_run_with_header.log
> @@ -0,0 +1,2 @@
> +TAP version 14
> +1..0
> --
> 2.32.0.93.g670b81a890-goog
>