From 19502fca854e943d852ac89de66e878635ea02a6 Mon Sep 17 00:00:00 2001
From: Tim Graham <timograham@gmail.com>
Date: Wed, 8 Jan 2025 16:31:26 -0500
Subject: [PATCH] add test_contained_by_subquery (broken)

---
 django_mongodb_backend/fields/array.py |  8 ++-
 tests/model_fields_/test_arrayfield.py | 74 ++++++++++++++++++++++++++
 2 files changed, 81 insertions(+), 1 deletion(-)

diff --git a/django_mongodb_backend/fields/array.py b/django_mongodb_backend/fields/array.py
index c60b65a2..860233be 100644
--- a/django_mongodb_backend/fields/array.py
+++ b/django_mongodb_backend/fields/array.py
@@ -260,7 +260,13 @@ class ArrayContainedBy(ArrayRHSMixin, FieldGetDbPrepValueMixin, Lookup):
     def as_mql(self, compiler, connection):
         lhs_mql = process_lhs(self, compiler, connection)
         value = process_rhs(self, compiler, connection)
-        return {"$and": [{"$ne": [lhs_mql, None]}, {"$setIsSubset": [lhs_mql, value]}]}
+        return {
+            "$and": [
+                {"$ne": [lhs_mql, None]},
+                {"$ne": [value, None]},
+                {"$setIsSubset": [lhs_mql, value]},
+            ]
+        }
 
 
 @ArrayField.register_lookup
diff --git a/tests/model_fields_/test_arrayfield.py b/tests/model_fields_/test_arrayfield.py
index 39ac55c3..a6c359cf 100644
--- a/tests/model_fields_/test_arrayfield.py
+++ b/tests/model_fields_/test_arrayfield.py
@@ -369,6 +369,80 @@ def test_contains_subquery(self):
             self.objs[1:3],
         )
 
+    def test_contained_by_subquery(self):
+        IntegerArrayModel.objects.create(field=[2, 3])
+        inner_qs = IntegerArrayModel.objects.values_list("field", flat=True)
+        self.assertSequenceEqual(
+            NullableIntegerArrayModel.objects.filter(field__contained_by=inner_qs[:1]),
+            self.objs[1:3],
+        )
+        IntegerArrayModel.objects.create(field=[2])
+        inner_qs = IntegerArrayModel.objects.filter(field__contained_by=OuterRef("field"))
+        # fails with  "both operands of $setIsSubset must be arrays. Second
+        # argument is of type: null"
+        self.assertSequenceEqual(
+            NullableIntegerArrayModel.objects.filter(Exists(inner_qs)),
+            self.objs[1:3],
+        )
+
+    # [
+    #    {
+    #        "$lookup": {
+    #            "as": "__subquery0",
+    #            "from": "model_fields__integerarraymodel",
+    #            "let": {"parent__field__0": "$field"},
+    #            "pipeline": [
+    #                {
+    #                    "$match": {
+    #                        "$expr": {
+    #                            "$and": [
+    #                                {"$ne": ["$field", None]},
+    #                                {"$ne": ["$$parent__field__0", None]},
+    #                                {"$setIsSubset": ["$field", "$$parent__field__0"]},
+    #                            ]
+    #                        }
+    #                    }
+    #                },
+    #                {"$project": {"a": {"$literal": 1}}},
+    #                {"$limit": 1},
+    #            ],
+    #        }
+    #    },
+    #    {
+    #        "$set": {
+    #            "__subquery0": {
+    #                "$cond": {
+    #                    "if": {
+    #                        "$or": [
+    #                            {"$eq": [{"$type": "$__subquery0"}, "missing"]},
+    #                            {"$eq": [{"$size": "$__subquery0"}, 0]},
+    #                        ]
+    #                    },
+    #                    "then": {},
+    #                    "else": {"$arrayElemAt": ["$__subquery0", 0]},
+    #                }
+    #            }
+    #        }
+    #    },
+    #    {
+    #        "$match": {
+    #            "$expr": {
+    #                "$eq": [
+    #                    {
+    #                        "$not": {
+    #                            "$or": [
+    #                                {"$eq": [{"$type": "$__subquery0.a"}, "missing"]},
+    #                                {"$eq": ["$__subquery0.a", None]},
+    #                            ]
+    #                        }
+    #                    },
+    #                    True,
+    #                ]
+    #            }
+    #        }
+    #    },
+    # ]
+
     def test_contains_including_expression(self):
         self.assertSequenceEqual(
             NullableIntegerArrayModel.objects.filter(