[PATCH v2 2/4] migrate-bitmaps-postcopy-test: Fix pylint warnings

[Max Reitz <mreitz@redhat.com>]

pylint complains that discards1_sha256 and all_discards_sha256 are first
set in non-__init__ methods.

These variables are not really class-variables anyway, so let them
instead be returned by start_postcopy(), thus silencing pylint.

Suggested-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
---
 .../tests/migrate-bitmaps-postcopy-test             | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/tests/qemu-iotests/tests/migrate-bitmaps-postcopy-test b/tests/qemu-iotests/tests/migrate-bitmaps-postcopy-test
index 584062b412..00ebb5c251 100755
--- a/tests/qemu-iotests/tests/migrate-bitmaps-postcopy-test
+++ b/tests/qemu-iotests/tests/migrate-bitmaps-postcopy-test
@@ -132,10 +132,10 @@ class TestDirtyBitmapPostcopyMigration(iotests.QMPTestCase):
 
         result = self.vm_a.qmp('x-debug-block-dirty-bitmap-sha256',
                                node='drive0', name='bitmap0')
-        self.discards1_sha256 = result['return']['sha256']
+        discards1_sha256 = result['return']['sha256']
 
         # Check, that updating the bitmap by discards works
-        assert self.discards1_sha256 != empty_sha256
+        assert discards1_sha256 != empty_sha256
 
         # We want to calculate resulting sha256. Do it in bitmap0, so, disable
         # other bitmaps
@@ -148,7 +148,7 @@ class TestDirtyBitmapPostcopyMigration(iotests.QMPTestCase):
 
         result = self.vm_a.qmp('x-debug-block-dirty-bitmap-sha256',
                                node='drive0', name='bitmap0')
-        self.all_discards_sha256 = result['return']['sha256']
+        all_discards_sha256 = result['return']['sha256']
 
         # Now, enable some bitmaps, to be updated during migration
         for i in range(2, nb_bitmaps, 2):
@@ -173,10 +173,11 @@ class TestDirtyBitmapPostcopyMigration(iotests.QMPTestCase):
 
         event_resume = self.vm_b.event_wait('RESUME')
         self.vm_b_events.append(event_resume)
-        return event_resume
+        return (event_resume, discards1_sha256, all_discards_sha256)
 
     def test_postcopy_success(self):
-        event_resume = self.start_postcopy()
+        event_resume, discards1_sha256, all_discards_sha256 = \
+                self.start_postcopy()
 
         # enabled bitmaps should be updated
         apply_discards(self.vm_b, discards2)
@@ -217,7 +218,7 @@ class TestDirtyBitmapPostcopyMigration(iotests.QMPTestCase):
         for i in range(0, nb_bitmaps, 5):
             result = self.vm_b.qmp('x-debug-block-dirty-bitmap-sha256',
                                    node='drive0', name='bitmap{}'.format(i))
-            sha = self.discards1_sha256 if i % 2 else self.all_discards_sha256
+            sha = discards1_sha256 if i % 2 else all_discards_sha256
             self.assert_qmp(result, 'return/sha256', sha)
 
     def test_early_shutdown_destination(self):
-- 
2.31.1