[Qemu-devel] [PULL 3/3] qemu-iotests: add no-op streaming test

[Jeff Cody <jcody@redhat.com>]

From: Alberto Garcia <berto@igalia.com>

This patch tests that in a partial block-stream operation, no data is
ever copied from the base image.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 5272a2aa57bc0b3f981f8b3e0c813e58a88c974b.1458566441.git.berto@igalia.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
---
 tests/qemu-iotests/030     | 18 ++++++++++++++++++
 tests/qemu-iotests/030.out |  4 ++--
 2 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/tests/qemu-iotests/030 b/tests/qemu-iotests/030
index 48a924c..3ac2443 100755
--- a/tests/qemu-iotests/030
+++ b/tests/qemu-iotests/030
@@ -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()
 
diff --git a/tests/qemu-iotests/030.out b/tests/qemu-iotests/030.out
index fa16b5c..6323079 100644
--- a/tests/qemu-iotests/030.out
+++ b/tests/qemu-iotests/030.out
@@ -1,5 +1,5 @@
-.............
+..............
 ----------------------------------------------------------------------
-Ran 13 tests
+Ran 14 tests
 
 OK
-- 
1.9.3