[PATCH 4/4] tests/qemu-iotests/qom-set-drive: replace with a differently sized node

["Denis V. Lunev" <den@openvz.org>]

All images in this test have the same size, so the test never reaches
the size change path of bdrv_replace_child_bs(). Add a node of a
different size and point a device at it.

The notification itself is not visible over QMP, so this only covers the
block layer side. What the device does with it is checked by
tests/qtest/virtio-scsi-test.c.

Signed-off-by: Denis V. Lunev <den@openvz.org>
---
 tests/qemu-iotests/tests/qom-set-drive     | 14 +++++++++++---
 tests/qemu-iotests/tests/qom-set-drive.out |  2 ++
 2 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/tests/qemu-iotests/tests/qom-set-drive b/tests/qemu-iotests/tests/qom-set-drive
index ec8ddac4fd..52d7eb96da 100755
--- a/tests/qemu-iotests/tests/qom-set-drive
+++ b/tests/qemu-iotests/tests/qom-set-drive
@@ -24,12 +24,15 @@ import iotests
 from iotests import imgfmt, log, qemu_img_create, QMPTestCase
 
 image_size = 1 * 1024 * 1024
-images = [os.path.join(iotests.test_dir, f'{i}.img') for i in range(0, 4)]
+images = [os.path.join(iotests.test_dir, f'{i}.img') for i in range(0, 5)]
+
+# node4 is deliberately larger, to cover a replacement which changes the size
+image_sizes = [image_size] * 4 + [2 * image_size]
 
 class TestQOMSetDrive(QMPTestCase):
     def setUp(self) -> None:
-        for image in images:
-            qemu_img_create('-f', imgfmt, image, str(image_size))
+        for image, size in zip(images, image_sizes):
+            qemu_img_create('-f', imgfmt, image, str(size))
 
         self.vm = iotests.VM()
         for i, image in enumerate(images):
@@ -68,6 +71,11 @@ class TestQOMSetDrive(QMPTestCase):
         log(self.vm.qmp('qom-get', path='/machine/peripheral/no-iot',
                         property='drive'))
 
+        log(self.vm.qmp('qom-set', path='/machine/peripheral/no-iot',
+                        property='drive', value='node4'))
+        log(self.vm.qmp('qom-get', path='/machine/peripheral/no-iot',
+                        property='drive'))
+
 if __name__ == '__main__':
     iotests.activate_logging()
     # LUKS would require special key-secret handling in add_blockdevs()
diff --git a/tests/qemu-iotests/tests/qom-set-drive.out b/tests/qemu-iotests/tests/qom-set-drive.out
index 7fc243dca6..6f6e5e2b31 100644
--- a/tests/qemu-iotests/tests/qom-set-drive.out
+++ b/tests/qemu-iotests/tests/qom-set-drive.out
@@ -4,6 +4,8 @@
 {"return": "node1"}
 {"return": {}}
 {"return": "node3"}
+{"return": {}}
+{"return": "node4"}
 .
 ----------------------------------------------------------------------
 Ran 1 tests
-- 
2.53.0