[PATCH 07/10] iotests: use subprocess.run where possible

[John Snow <jsnow@redhat.com>]

pylint 2.8.x adds warnings whenever we use Popen calls without using
'with', so it's desirable to convert synchronous calls to run()
invocations where applicable.

(Though, this trades one pylint warning for another due to a pylint bug,
which I've silenced with a pragma and a link to the bug.)

Signed-off-by: John Snow <jsnow@redhat.com>
---
 tests/qemu-iotests/iotests.py | 19 +++++++++++--------
 1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/tests/qemu-iotests/iotests.py b/tests/qemu-iotests/iotests.py
index 5af01828951..46deb7f4dd4 100644
--- a/tests/qemu-iotests/iotests.py
+++ b/tests/qemu-iotests/iotests.py
@@ -113,15 +113,16 @@ def qemu_tool_pipe_and_status(tool: str, args: Sequence[str],
     Run a tool and return both its output and its exit code
     """
     stderr = subprocess.STDOUT if connect_stderr else None
-    subp = subprocess.Popen(args,
-                            stdout=subprocess.PIPE,
-                            stderr=stderr,
-                            universal_newlines=True)
-    output = subp.communicate()[0]
-    if subp.returncode < 0:
+    res = subprocess.run(args,
+                         stdout=subprocess.PIPE,
+                         stderr=stderr,
+                         universal_newlines=True,
+                         check=False)
+    output = res.stdout
+    if res.returncode < 0:
         cmd = ' '.join(args)
-        sys.stderr.write(f'{tool} received signal {-subp.returncode}: {cmd}\n')
-    return (output, subp.returncode)
+        sys.stderr.write(f'{tool} received signal {-res.returncode}: {cmd}\n')
+    return (output, res.returncode)
 
 def qemu_img_pipe_and_status(*args: str) -> Tuple[str, int]:
     """
@@ -1153,6 +1154,8 @@ def _verify_virtio_scsi_pci_or_ccw() -> None:
 
 
 def supports_quorum():
+    # https://github.com/PyCQA/astroid/issues/689
+    # pylint: disable=unsupported-membership-test
     return 'quorum' in qemu_img_pipe('--help')
 
 def verify_quorum():
-- 
2.30.2