Change in vdsm[master]: python3: Fix UUID packing/unpacking on python 3

[Code Review]

From Dan Kenigsberg :

Dan Kenigsberg has posted comments on this change.

Change subject: python3: Fix UUID packing/unpacking on python 3
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Patch Set 9:

(1 comment)

https://gerrit.ovirt.org/#/c/78632/9/tests/storage/misc_test.py
File tests/storage/misc_test.py:

Line 459:         Test that the uuid that was packed can be unpacked without being
Line 460:         changed
Line 461:         """
Line 462:         for i in range(1000):
Line 463:             origUuid = str(uuid.uuid4())
> We test here 1000 random uuids, better than small list of random uuids. And

I have nothing against testing 1000 numbers. What I don't like is surprises in tests.

Assume your test fails on a single random uuid on a single CI run by a single developer. Nobody would notice. All they'd see is a fluke -1, and they'd re-trigger the job.

A safe approach is to have a predictable list of number. If we introduce a bug that makes the test fail on one of them, it would keep on failing.

r = random.Random(42)
for _ in range(1000):
  origUiid = str(uuid.UUID(int=r.randint(0, 2**128-1)))
  ...

it's not terribly important for this simple test, but I think that uncontrolled randomness is a bad practice for testing, and it should be avoided.
Line 464:             packedUuid = misc.packUuid(origUuid)
Line 465:             self.assertEqual(misc.unpackUuid(packedUuid), origUuid)
Line 466: 
Line 467: