iotests.py: filter out successful output of qemu-img create

The only "feature" of this "Formatting ..." line is that we have to
update it every time we add new option. Let's drop it.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20211223160144.1097696-10-vsementsov@virtuozzo.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>

1 files changed, 8 insertions, 2 deletions

diff --git a/tests/qemu-iotests/iotests.py b/tests/qemu-iotests/iotests.py
index c382c527c8..65780c6098 100644
--- a/tests/qemu-iotests/iotests.py
+++ b/tests/qemu-iotests/iotests.py
@@ -150,7 +150,9 @@ def qemu_tool_popen(args: Sequence[str],
 
 
 def qemu_tool_pipe_and_status(tool: str, args: Sequence[str],
-                              connect_stderr: bool = True) -> Tuple[str, int]:
+                              connect_stderr: bool = True,
+                              drop_successful_output: bool = False) \
+        -> Tuple[str, int]:
     """
     Run a tool and return both its output and its exit code
     """
@@ -160,6 +162,8 @@ def qemu_tool_pipe_and_status(tool: str, args: Sequence[str],
             cmd = ' '.join(args)
             sys.stderr.write(f'{tool} received signal \
                                {-subp.returncode}: {cmd}\n')
+        if drop_successful_output and subp.returncode == 0:
+            output = ''
         return (output, subp.returncode)
 
 def qemu_img_create_prepare_args(args: List[str]) -> List[str]:
@@ -204,8 +208,10 @@ def qemu_img_pipe_and_status(*args: str) -> Tuple[str, int]:
     """
     Run qemu-img and return both its output and its exit code
     """
+    is_create = bool(args and args[0] == 'create')
     full_args = qemu_img_args + qemu_img_create_prepare_args(list(args))
-    return qemu_tool_pipe_and_status('qemu-img', full_args)
+    return qemu_tool_pipe_and_status('qemu-img', full_args,
+                                     drop_successful_output=is_create)
 
 def qemu_img(*args: str) -> int:
     '''Run qemu-img and return the exit code'''