Edits.

Author: WaVEV

django_mongodb_backend/compiler.py

@@ -884,7 +884,7 @@ def execute_sql(self, result_type):
                     )
             prepared = field.get_db_prep_save(value, connection=self.connection)
             if is_direct_value(value):
-                prepared = {"$literal": prepared} if isinstance(value, str) else prepared
+                prepared = {"$literal": prepared}
             else:
                 prepared = prepared.as_mql(self, self.connection, as_expr=True)
             values[field.column] = prepared

django_mongodb_backend/expressions/builtins.py

@@ -211,8 +211,8 @@ def when(self, compiler, connection):
 
 def value(self, compiler, connection, as_expr=False):  # noqa: ARG001
     value = self.value
-    if isinstance(value, (list, int, str)) and as_expr:
-        # Wrap lists, numbers, and strings in $literal to avoid ambiguity when Value
+    if isinstance(value, (list, int, str, dict, tuple)) and as_expr:
+        # Wrap lists, numbers, strings, dict and tuple in $literal to avoid ambiguity when Value
         # is used in queries' aggregate or update_many's $set.
         return {"$literal": value}
     if isinstance(value, Decimal):

tests/basic_/models.py

@@ -6,3 +6,8 @@ class Author(models.Model):
 
     def __str__(self):
         return self.name
+
+
+class Book(models.Model):
+    name = models.CharField(max_length=10)
+    data = models.JSONField(null=True)

tests/basic_/tests.py

@@ -3,7 +3,7 @@
 
 from django_mongodb_backend.test import MongoTestCaseMixin
 
-from .models import Author
+from .models import Author, Book
 
 
 class SaveDollarPrefixTests(MongoTestCaseMixin, TestCase):
@@ -45,6 +45,38 @@ def test_update_dollar_prefix_in_value_expression(self):
             [{"$set": {"name": {"$literal": "$updated"}}}],
         )
 
+    def test_update_dict_value(self):
+        """MQL-like dict Value() expressions are correctly handled on update."""
+        obj = Book.objects.create(name="foobar", data={})
+        obj.data = Value({"$concat": ["$name", "-", "$name"]})
+        obj.save()
+        obj.refresh_from_db()
+        self.assertEqual(obj.data, {"$concat": ["$name", "-", "$name"]})
+
+    def test_update_dict(self):
+        """MQL-like dict updates are correctly handled on update."""
+        obj = Book.objects.create(name="foobar")
+        obj.data = {"$concat": ["$name", "-", "$name"]}
+        obj.save()
+        obj.refresh_from_db()
+        self.assertEqual(obj.data, {"$concat": ["$name", "-", "$name"]})
+
+    def test_update_tuple(self):
+        """MQL-like tuple updates are correctly handled on update."""
+        obj = Book.objects.create(name="foobar")
+        obj.data = ("$name", "-", "$name")
+        obj.save()
+        obj.refresh_from_db()
+        self.assertEqual(obj.data, ["$name", "-", "$name"])
+
+    def test_update_tuple_value(self):
+        """MQL-like tuple Value() expressions are correctly handled on update."""
+        obj = Book.objects.create(name="foobar")
+        obj.data = Value(("$name", "-", "$name"))
+        obj.save()
+        obj.refresh_from_db()
+        self.assertEqual(obj.data, ["$name", "-", "$name"])
+
 
 class QueryDollarPrefixTests(MongoTestCaseMixin, TestCase):
     def test_query_injection(self):