kunit: tool: better handling of quasi-bool args (--json, --raw_output)

Problem:

What does this do?
$ kunit.py run --json
Well, it runs all the tests and prints test results out as JSON.

And next is
$ kunit.py run my-test-suite --json
This runs just `my-test-suite` and prints results out as JSON.

But what about?
$ kunit.py run --json my-test-suite
This runs all the tests and stores the json results in a "my-test-suite"
file.

Why:
--json, and now --raw_output are actually string flags. They just have a
default value. --json in particular takes the name of an output file.

It was intended that you'd do
$ kunit.py run --json=my_output_file my-test-suite
if you ever wanted to specify the value.

Workaround:
It doesn't seem like there's a way to make
https://docs.python.org/3/library/argparse.html only accept arg values
after a '='.

I believe that `--json` should "just work" regardless of where it is.
So this patch automatically rewrites a bare `--json` to `--json=stdout`.

That makes the examples above work the same way.
Add a regression test that can catch this for --raw_output.

Fixes: 6a499c9c42d0 ("kunit: tool: make --raw_output support only showing kunit output")
Signed-off-by: Daniel Latypov <dlatypov@google.com>
Tested-by: David Gow <davidgow@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

1 files changed, 8 insertions, 0 deletions

diff --git a/tools/testing/kunit/kunit_tool_test.py b/tools/testing/kunit/kunit_tool_test.py
index 619c4554cbff..1edcc8373b4e 100755
--- a/tools/testing/kunit/kunit_tool_test.py
+++ b/tools/testing/kunit/kunit_tool_test.py
@@ -408,6 +408,14 @@ class KUnitMainTest(unittest.TestCase):
 			self.assertNotEqual(call, mock.call(StrContains('Testing complete.')))
 			self.assertNotEqual(call, mock.call(StrContains(' 0 tests run')))
 
+	def test_run_raw_output_does_not_take_positional_args(self):
+		# --raw_output is a string flag, but we don't want it to consume
+		# any positional arguments, only ones after an '='
+		self.linux_source_mock.run_kernel = mock.Mock(return_value=[])
+		kunit.main(['run', '--raw_output', 'filter_glob'], self.linux_source_mock)
+		self.linux_source_mock.run_kernel.assert_called_once_with(
+			args=None, build_dir='.kunit', filter_glob='filter_glob', timeout=300)
+
 	def test_exec_timeout(self):
 		timeout = 3453
 		kunit.main(['exec', '--timeout', str(timeout)], self.linux_source_mock)