This turns run_linters() into a bit of a hybrid test; returning non-zero
on failed execution while also printing diffable information. This is
done for the benefit of the avocado simple test runner, which will soon
be attempting to execute this test from a different environment.

(Note: universal_newlines is added to the pylint invocation for type
consistency with the mypy run -- it's not strictly necessary, but it
avoids some typing errors caused by our re-use of the 'p' variable.)

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
---
 tests/qemu-iotests/297 | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/tests/qemu-iotests/297 b/tests/qemu-iotests/297
index b2bf7928c5d..ca9ee72d2fa 100755
--- a/tests/qemu-iotests/297
+++ b/tests/qemu-iotests/297
@@ -73,19 +73,22 @@ def run_linters(
     files: List[str],
     directory: str = '.',
     env: Optional[Mapping[str, str]] = None,
-) -> None:
+) -> int:
+    ret = 0
 
     print('=== pylint ===')
     sys.stdout.flush()
 
     # Todo notes are fine, but fixme's or xxx's should probably just be
     # fixed (in tests, at least)
-    subprocess.run(
+    p = subprocess.run(
         ('python3', '-m', 'pylint', '--score=n', '--notes=FIXME,XXX', *files),
         cwd=directory,
         env=env,
         check=False,
+        universal_newlines=True,
     )
+    ret += p.returncode
 
     print('=== mypy ===')
     sys.stdout.flush()
@@ -118,9 +121,12 @@ def run_linters(
             universal_newlines=True
         )
 
+        ret += p.returncode
         if p.returncode != 0:
             print(p.stdout)
 
+    return ret
+
 
 def main() -> None:
     for linter in ('pylint-3', 'mypy'):
-- 
2.31.1