Set expect failure to tests that have get ordering issue.

Author: WaVEV

django_mongodb/compiler.py

@@ -359,7 +359,9 @@ def build_query(self, columns=None):
         query.project_fields = self.get_project_fields(columns, ordering=query.ordering)
         try:
             where = getattr(self, "where", self.query.where)
-            query.mongo_query = {"$expr": where.as_mql(self, self.connection)}
+            query.mongo_query = (
+                {"$expr": where.as_mql(self, self.connection)} if where is not None else {}
+            )
         except FullResultSet:
             query.mongo_query = {}
         return query

django_mongodb/features.py

@@ -104,16 +104,21 @@ class DatabaseFeatures(BaseDatabaseFeatures):
         "queries.test_explain.ExplainUnsupportedTests.test_message",
         # filter() on related model + update() doesn't work.
         "queries.tests.Queries5Tests.test_ticket9848",
-        # Variance is not implemented in mongo as an aggregation,
-        # we should transform it into StdDev * 2.
-        "aggregation.test_filter_argument.FilteredAggregateTests.test_filtered_numerical_aggregates",
         # Sum returns 0 instead of None in mongodb.
         "aggregation.test_filter_argument.FilteredAggregateTests.test_plain_annotate",
         "aggregation.tests.AggregateTestCase.test_aggregation_default_passed_another_aggregate",
         "aggregation.tests.AggregateTestCase.test_annotation_expressions",
         "aggregation.tests.AggregateTestCase.test_reverse_fkey_annotate",
         # Manage empty result when the flag elide_empty is False
         "aggregation.tests.AggregateTestCase.test_empty_result_optimization",
+        # Order is not working well for aggregates.
+        "aggregation.tests.AggregateTestCase.test_annotate_values_list",
+        "aggregation.tests.AggregateTestCase.test_combine_different_types",
+        "aggregation.tests.AggregateTestCase.test_grouped_annotation_in_group_by",
+        "aggregation.tests.AggregateTestCase.test_non_grouped_annotation_not_in_group_by",
+        "aggregation.tests.AggregateTestCase.test_values_annotation_with_expression",
+        "aggregation.tests.AggregateTestCase.test_annotate_ordering",
+        "aggregation.tests.AggregateTestCase.test_even_more_aggregate",
     }
     # $bitAnd, #bitOr, and $bitXor are new in MongoDB 6.3.
     _django_test_expected_failures_bitwise = {

django_mongodb/functions.py

@@ -140,7 +140,9 @@ def count(self, compiler, connection, **extra_context):
             node = self
             lhs_mql = process_lhs(self, compiler, connection)
             null_cond = {"$in": [{"$type": lhs_mql}, ["missing", "null"]]}
-            cond = {"$cond": {"if": null_cond, "then": 0, "else": lhs_mql if self.distinct else 1}}
+            cond = {
+                "$cond": {"if": null_cond, "then": None, "else": lhs_mql if self.distinct else 1}
+            }
         return {"$sum": cond}
 
     lhs_mql = process_lhs(self, compiler, connection)