fix QuerySet.update() with related model instance

Author: timgraham

.github/workflows/test-python.yml

@@ -74,7 +74,9 @@ jobs:
  model_fields.test_datetimefield
  model_fields.test_decimalfield
  model_fields.test_charfield
+ model_fields.test_floatfield
  model_fields.test_textfield
+ model_fields.test_uuid.TestAsPrimaryKey.test_update_with_related_model_instance
  or_lookups
 
  docs:

django_mongodb/compiler.py

@@ -223,6 +223,15 @@ def execute_sql(self, result_type):
  self.pre_sql_setup()
  values = []
  for field, _, value in self.query.values:
+ if hasattr(value, "prepare_database_save"):
+ if field.remote_field:
+ value = value.prepare_database_save(field)
+ else:
+ raise TypeError(
+ f"Tried to update field {field} with a model "
+ f"instance, {value!r}. Use a value compatible with "
+ f"{field.__class__.__name__}."
+ )
  prepared = field.get_db_prep_save(value, connection=self.connection)
  values.append((field, prepared))
  return self.update(values)

pyproject.toml

@@ -104,6 +104,7 @@ ignore = [
  "ARG002", # Unused method argument:
  "S101", # Use of `assert` detected
  "RUF012", # Mutable class attributes should be annotated with `typing.ClassVar`
+ "PLW2901", # `for` loop variable `value` overwritten by assignment target
 ]
 unfixable = []
 exclude = []