test/pybind/rbd: don't ignore from_snapshot in check_diff()

Despite the test in test_diff_iterate() being correct, it started
failing:

    >       check_diff(self.image, 0, IMG_SIZE, 'snap1', [(0, 512, False)])
    ...
    a = [], b = [(0, 512, False)]
    ...
    >       assert a == b
    E       AssertionError

This is because check_diff() drops 'snap1' argument on the floor and
passes None to image.diff_iterate() instead.  This goes back to 2013,
see commit e88fe3cbbc8f ("rbd.py: add some missing functions").

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
(cherry picked from commit f8ced6d1fe667864bee224104c23b62a2c1c0bfc)

diff --git a/src/test/pybind/test_rbd.py b/src/test/pybind/test_rbd.py
index 0ce3c0dd90caa5d98ace848f1d49d8678bbe6c06..df47b0d2976be816b5598475959e5841768299ba 100644 (file)
--- a/src/test/pybind/test_rbd.py
+++ b/src/test/pybind/test_rbd.py
@@ -1471,7 +1471,7 @@ def check_diff(image, offset, length, from_snapshot, expected):
     extents = []
     def cb(offset, length, exists):
         extents.append((offset, length, exists))
-    image.diff_iterate(0, IMG_SIZE, None, cb)
+    image.diff_iterate(0, IMG_SIZE, from_snapshot, cb)
     eq(extents, expected)
 
 class TestClone(object):