Refactor.

Author: WaVEV

README.md

@@ -114,8 +114,6 @@ from the new application's `apps.py` file.
 - `QuerySet.delete()` and `update()` do not support queries that span multiple
   collections.
 
-- `QuerySet` in `QuerySet.annotate()` aren't supported.
-
 - `DateTimeField` doesn't support microsecond precision, and correspondingly,
   `DurationField` stores milliseconds rather than microseconds.
 

django_mongodb/compiler.py

@@ -685,9 +685,7 @@ def execute_sql(self, result_type=MULTI):
     def check_query(self):
         super().check_query()
         if not self.single_alias:
-            raise NotSupportedError(
-                "Cannot use QuerySet.delete() when querying across multiple collections on MongoDB."
-            )
+            raise NotSupportedError("Cannot use QuerySet.delete() when a subquery is required.")
 
     def get_where(self):
         return self.query.where

django_mongodb/features.py

@@ -326,23 +326,18 @@ def django_test_expected_failures(self):
             "aggregation.tests.AggregateAnnotationPruningTests.test_unused_aliased_aggregate_pruned",
             "aggregation.tests.AggregateAnnotationPruningTests.test_referenced_aggregate_annotation_kept",
             "aggregation.tests.AggregateTestCase.test_count_star",
-            "aggregation.tests.AggregateAnnotationPruningTests.test_referenced_composed_subquery_requires_wrapping",
-            "aggregation.tests.AggregateAnnotationPruningTests.test_referenced_subquery_requires_wrapping",
-            "aggregation.tests.AggregateTestCase.test_aggregation_subquery_annotation",
-            "aggregation.tests.AggregateTestCase.test_aggregation_subquery_annotation_related_field",
             "delete.tests.DeletionTests.test_only_referenced_fields_selected",
             "expressions.tests.ExistsTests.test_optimizations",
             "lookup.tests.LookupTests.test_in_ignore_none",
             "lookup.tests.LookupTests.test_textfield_exact_null",
             "migrations.test_commands.MigrateTests.test_migrate_syncdb_app_label",
             "migrations.test_commands.MigrateTests.test_migrate_syncdb_deferred_sql_executed_with_schemaeditor",
-            "queries.tests.ExcludeTests.test_exclude_multivalued_exists",
             "queries.tests.ExistsSql.test_exists",
             "queries.tests.Queries6Tests.test_col_alias_quoted",
             "schema.tests.SchemaTests.test_rename_column_renames_deferred_sql_references",
             "schema.tests.SchemaTests.test_rename_table_renames_deferred_sql_references",
         },
-        "Subqueries cannot be used in delete operations": {
+        "Cannot use QuerySet.delete() when a subquery is required.": {
             "delete_regress.tests.DeleteTests.test_self_reference_with_through_m2m_at_second_level",
             "many_to_many.tests.ManyToManyTests.test_assign",
             "many_to_many.tests.ManyToManyTests.test_assign_ids",

django_mongodb/lookups.py

@@ -36,6 +36,12 @@ def field_resolve_expression_parameter(self, compiler, connection, sql, param):
 def in_(self, compiler, connection):
     if isinstance(self.lhs, MultiColSource):
         raise NotImplementedError("MultiColSource is not supported.")
+    db_rhs = getattr(self.rhs, "_db", None)
+    if db_rhs is not None and db_rhs != connection.alias:
+        raise ValueError(
+            "Subqueries aren't allowed across different databases. Force "
+            "the inner query to be evaluated using `list(inner_query)`."
+        )
     return builtin_lookup(self, compiler, connection)
 
 

django_mongodb/query_utils.py

@@ -27,12 +27,6 @@ def process_lhs(node, compiler, connection):
 
 def process_rhs(node, compiler, connection):
     rhs = node.rhs
-    db_rhs = getattr(rhs, "_db", None)
-    if db_rhs is not None and db_rhs != connection.alias:
-        raise ValueError(
-            "Subqueries aren't allowed across different databases. Force "
-            "the inner query to be evaluated using `list(inner_query)`."
-        )
     if hasattr(rhs, "as_mql"):
         if getattr(rhs, "subquery", False):
             value = rhs.as_mql(compiler, connection, lookup_name=node.lookup_name)