From fe10f4559b97164a6e5649af13f5dbd3a77ba99d Mon Sep 17 00:00:00 2001
From: James Page <james.page@canonical.com>
Date: Mon, 22 Jan 2024 17:08:52 +0000
Subject: [PATCH] fixture: Drop use of OrderedDict for Python compat

Python >= 3.12 changes the string representation of an OrderedDict
which changes the md5 digest of an object; this causes a regression
on the test_get_hashes unit test on newer Pythons.

Subclass OrderedDict to revert the change in __repr__ in order provide
a represenation which is consistent across all supported Python versions.

Closes-Bug: #2046220
Change-Id: I9b0d9e7b501f3de425bc2c342f25b8ea2248da20
---
 oslo_versionedobjects/fixture.py            | 19 ++++++++++++++++++-
 oslo_versionedobjects/tests/test_fixture.py |  6 +++---
 2 files changed, 21 insertions(+), 4 deletions(-)

diff --git a/oslo_versionedobjects/fixture.py b/oslo_versionedobjects/fixture.py
index 9661c70e..eccacd98 100644
--- a/oslo_versionedobjects/fixture.py
+++ b/oslo_versionedobjects/fixture.py
@@ -26,6 +26,7 @@ import copy
 import datetime
 import inspect
 import logging
+from reprlib import recursive_repr
 from unittest import mock
 
 import fixtures
@@ -101,6 +102,22 @@ def compare_obj(test, obj, db_obj, subs=None, allow_missing=None,
             test.assertEqual(db_val, obj_val)
 
 
+class OsloOrderedDict(OrderedDict):
+    """Oslo version of OrderedDict for Python consistency."""
+
+    @recursive_repr()
+    def __repr__(self):
+        if not self:
+            return '%s()' % self.__class__.__bases__[0].__name__
+        # NOTE(jamespage):
+        # Python >= 3.12 uses a dict instead of a list which changes the
+        # repr of the versioned object and its associated hash value
+        # Switch back to using list an use super class name.
+        return '%s(%r)' % (
+            self.__class__.__bases__[0].__name__, list(self.items())
+        )
+
+
 class FakeIndirectionAPI(base.VersionedObjectIndirectionAPI):
     def __init__(self, serializer=None):
         super(FakeIndirectionAPI, self).__init__()
@@ -263,7 +280,7 @@ class ObjectVersionChecker(object):
         # and return value changes, for example).
         if hasattr(obj_class, 'child_versions'):
             relevant_data = (obj_fields, methods,
-                             OrderedDict(
+                             OsloOrderedDict(
                                  sorted(obj_class.child_versions.items())))
         else:
             relevant_data = (obj_fields, methods)
diff --git a/oslo_versionedobjects/tests/test_fixture.py b/oslo_versionedobjects/tests/test_fixture.py
index f991f745..e6a84a55 100644
--- a/oslo_versionedobjects/tests/test_fixture.py
+++ b/oslo_versionedobjects/tests/test_fixture.py
@@ -12,7 +12,6 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-import collections
 import copy
 import datetime
 import hashlib
@@ -565,8 +564,9 @@ class TestObjectVersionChecker(test.TestCase):
         exp_fields = sorted(list(MyObject.fields.items()))
         exp_methods = sorted([('remotable_method', argspec),
                               ('remotable_classmethod', argspec)])
-        exp_child_versions = collections.OrderedDict(sorted(
-            child_versions.items()))
+        exp_child_versions = fixture.OsloOrderedDict(
+            sorted(child_versions.items())
+        )
         exp_relevant_data = (exp_fields, exp_methods, exp_child_versions)
 
         # NOTE(hberaud) the following hashlib usage will emit a bandit