@@ -91,6 +91,24 @@ class TestSingleDrive(iotests.QMPTestCase):
qemu_io('-f', iotests.imgfmt, '-c', 'map', test_img),
'image file map does not match backing file after streaming')
+ def test_stream_no_op(self):
+ self.assert_no_active_block_jobs()
+
+ # The image map is empty before the operation
+ empty_map = qemu_io('-f', iotests.imgfmt, '-c', 'map', test_img)
+
+ # This is a no-op: no data should ever be copied from the base image
+ result = self.vm.qmp('block-stream', device='drive0', base=mid_img)
+ self.assert_qmp(result, 'return', {})
+
+ self.wait_until_completed()
+
+ self.assert_no_active_block_jobs()
+ self.vm.shutdown()
+
+ self.assertEqual(qemu_io('-f', iotests.imgfmt, '-c', 'map', test_img),
+ empty_map, 'image file map changed after a no-op')
+
def test_stream_partial(self):
self.assert_no_active_block_jobs()
@@ -1,5 +1,5 @@
-.............
+..............
----------------------------------------------------------------------
-Ran 13 tests
+Ran 14 tests
OK