[5.0] Add django.db.models.GeneratedField (#1944)

* Add django.db.models.GeneratedField

* Fix all the known test failures for GeneratedField

* Ignore cached_col cached_property issues

* Removed default values from GeneratedField

* Apply suggestions from code review

---------

Co-authored-by: Nikita Sobolev <mail@sobolevn.me>

django-stubs/db/models/__init__.pyi

@@ -74,6 +74,7 @@ from .fields import URLField as URLField
 from .fields import UUIDField as UUIDField
 from .fields.files import FileField as FileField
 from .fields.files import ImageField as ImageField
+from .fields.generated import GeneratedField as GeneratedField
 from .fields.json import JSONField as JSONField
 from .fields.proxy import OrderWrt as OrderWrt
 from .fields.related import ForeignKey as ForeignKey

django-stubs/db/models/fields/generated.pyi

@@ -0,0 +1,47 @@
+from typing import Any, Iterable, Literal
+
+from django.core.validators import _ValidatorCallable
+from django.db import models
+from django.db.backends.base.base import BaseDatabaseWrapper
+from django.db.models.expressions import Expression
+from django.db.models.fields import _ErrorMessagesMapping, _FieldChoices
+from django.db.models.sql import Query
+from django.utils.datastructures import DictWrapper
+from django.utils.functional import _StrOrPromise
+
+class GeneratedField(models.Field):
+    generated: Literal[True]
+    db_returning: Literal[True]
+    _query: Query | None
+    output_field: models.Field | None
+
+    def __init__(
+        self,
+        *,
+        expression: Expression,
+        output_field: models.Field,
+        db_persist: bool | None = ...,
+        verbose_name: _StrOrPromise | None = ...,
+        name: str | None = ...,
+        primary_key: bool = ...,
+        unique: bool = ...,
+        blank: bool = ...,
+        null: bool = ...,
+        default: Any = ...,
+        editable: bool = ...,
+        auto_created: bool = ...,
+        serialize: bool = ...,
+        unique_for_date: str | None = ...,
+        unique_for_month: str | None = ...,
+        unique_for_year: str | None = ...,
+        choices: _FieldChoices | None = ...,
+        help_text: _StrOrPromise = ...,
+        db_column: str | None = ...,
+        db_comment: str | None = ...,
+        db_tablespace: str | None = ...,
+        validators: Iterable[_ValidatorCallable] = ...,
+        error_messages: _ErrorMessagesMapping | None = ...,
+        **kwargs: Any,
+    ) -> None: ...
+    def generated_sql(self, connection: BaseDatabaseWrapper) -> tuple[str, Any]: ...
+    def db_type_parameters(self, connection: BaseDatabaseWrapper) -> DictWrapper: ...

scripts/stubtest/allowlist.txt

@@ -182,6 +182,7 @@ django.contrib.gis.db.models.ForeignObjectRel.name
 django.contrib.gis.db.models.ForeignObjectRel.one_to_many
 django.contrib.gis.db.models.ForeignObjectRel.one_to_one
 django.contrib.gis.db.models.ForeignObjectRel.related_model
+django.contrib.gis.db.models.GeneratedField.cached_col
 django.contrib.gis.db.models.IntegerField.validators
 django.contrib.gis.db.models.Lookup.contains_aggregate
 django.contrib.gis.db.models.Lookup.contains_over_clause
@@ -300,6 +301,7 @@ django.db.models.ForeignObjectRel.name
 django.db.models.ForeignObjectRel.one_to_many
 django.db.models.ForeignObjectRel.one_to_one
 django.db.models.ForeignObjectRel.related_model
+django.db.models.GeneratedField.cached_col
 django.db.models.IntegerField.validators
 django.db.models.Lookup.contains_aggregate
 django.db.models.Lookup.contains_over_clause
@@ -313,6 +315,7 @@ django.db.models.fields.DecimalField.validators
 django.db.models.fields.Field.cached_col
 django.db.models.fields.Field.validators
 django.db.models.fields.IntegerField.validators
+django.db.models.fields.generated.GeneratedField.cached_col
 django.db.models.fields.related.ForeignObject.foreign_related_fields
 django.db.models.fields.related.ForeignObject.local_related_fields
 django.db.models.fields.related.ForeignObject.related_fields

scripts/stubtest/allowlist_todo_django50.txt

@@ -70,7 +70,6 @@ django.contrib.gis.db.models.ForeignObject.get_joining_fields
 django.contrib.gis.db.models.ForeignObject.get_reverse_joining_fields
 django.contrib.gis.db.models.ForeignObjectRel.get_joining_fields
 django.contrib.gis.db.models.Func.allowed_default
-django.contrib.gis.db.models.GeneratedField
 django.contrib.gis.db.models.Lookup.allowed_default
 django.contrib.gis.db.models.Prefetch.get_current_querysets
 django.contrib.gis.db.models.Q.identity
@@ -181,7 +180,6 @@ django.db.models.ForeignObject.get_joining_fields
 django.db.models.ForeignObject.get_reverse_joining_fields
 django.db.models.ForeignObjectRel.get_joining_fields
 django.db.models.Func.allowed_default
-django.db.models.GeneratedField
 django.db.models.Lookup.allowed_default
 django.db.models.Prefetch.get_current_querysets
 django.db.models.Q.identity
@@ -206,7 +204,6 @@ django.db.models.expressions.When.allowed_default
 django.db.models.fields.Field.__init__
 django.db.models.fields.Field._get_flatchoices
 django.db.models.fields.Field.generated
-django.db.models.fields.generated
 django.db.models.fields.related.ForeignKey.cast_db_type
 django.db.models.fields.related.ForeignObject.get_joining_fields
 django.db.models.fields.related.ForeignObject.get_reverse_joining_fields