Increase accuracy of ModelAdmin types (#375)

* Increase accuracy of ModelAdmin types

* Add comment for regression test

django-stubs/contrib/admin/options.pyi

@@ -1,5 +1,9 @@
 from collections import OrderedDict
-from typing import Any, Callable, Dict, Iterator, List, Optional, Sequence, Set, Tuple, Type, Union
+from typing import Any, Callable, Dict, Iterator, List, Optional, Sequence, Set, Tuple, Type, Union, Mapping, TypeVar
+
+from django.forms.forms import BaseForm
+from django.forms.formsets import BaseFormSet
+from typing_extensions import Literal, TypedDict
 
 from django.contrib.admin.filters import ListFilter
 from django.contrib.admin.models import LogEntry
@@ -26,8 +30,10 @@ from django.db.models.fields import Field
 
 IS_POPUP_VAR: str
 TO_FIELD_VAR: str
-HORIZONTAL: Any
+HORIZONTAL: Literal[1] = ...
-VERTICAL: Any
+VERTICAL: Literal[2] = ...
+
+_Direction = Union[Literal[1], Literal[2]]
 
 def get_content_type_for_model(obj: Union[Type[Model], Model]) -> ContentType: ...
 def get_ul_class(radio_style: int) -> str: ...
@@ -37,21 +43,35 @@ class IncorrectLookupParameters(Exception): ...
 FORMFIELD_FOR_DBFIELD_DEFAULTS: Any
 csrf_protect_m: Any
 
+class _OptionalFieldOpts(TypedDict, total=False):
+    classes: Sequence[str]
+    description: str
+
+class _FieldOpts(_OptionalFieldOpts, total=True):
+    fields: Sequence[Union[str, Sequence[str]]]
+
+# Workaround for mypy issue, a Sequence type should be preferred here.
+# https://github.com/python/mypy/issues/8921
+# _FieldsetSpec = Sequence[Tuple[Optional[str], _FieldOpts]]
+_T = TypeVar("_T")
+_ListOrTuple = Union[Tuple[_T, ...], List[_T]]
+_FieldsetSpec = _ListOrTuple[Tuple[Optional[str], _FieldOpts]]
+
 class BaseModelAdmin:
-    autocomplete_fields: Any = ...
+    autocomplete_fields: Sequence[str] = ...
-    raw_id_fields: Any = ...
+    raw_id_fields: Sequence[str] = ...
-    fields: Any = ...
+    fields: Sequence[Union[str, Sequence[str]]] = ...
-    exclude: Any = ...
+    exclude: Sequence[str] = ...
-    fieldsets: Any = ...
+    fieldsets: _FieldsetSpec = ...
-    form: Any = ...
+    form: Type[BaseForm] = ...
-    filter_vertical: Any = ...
+    filter_vertical: Sequence[str] = ...
-    filter_horizontal: Any = ...
+    filter_horizontal: Sequence[str] = ...
-    radio_fields: Any = ...
+    radio_fields: Mapping[str, _Direction] = ...
-    prepopulated_fields: Any = ...
+    prepopulated_fields: Mapping[str, Sequence[str]] = ...
-    formfield_overrides: Any = ...
+    formfield_overrides: Mapping[Type[Field], Mapping[str, Any]] = ...
-    readonly_fields: Any = ...
+    readonly_fields: Sequence[Union[str, Callable[[Model], Any]]] = ...
-    ordering: Any = ...
+    ordering: Sequence[str] = ...
-    sortable_by: Any = ...
+    sortable_by: Sequence[str] = ...
     view_on_site: bool = ...
     show_full_result_count: bool = ...
     checks_class: Any = ...
@@ -93,7 +113,7 @@ class BaseModelAdmin:
     def has_module_permission(self, request: HttpRequest) -> bool: ...
 
 class ModelAdmin(BaseModelAdmin):
-    list_display: Sequence[Union[str, Callable]] = ...
+    list_display: Sequence[Union[str, Callable[[Model], Any]]] = ...
     list_display_links: Optional[Sequence[Union[str, Callable]]] = ...
     list_filter: Sequence[Union[str, Type[ListFilter], Tuple[str, Type[ListFilter]]]] = ...
     list_select_related: Union[bool, Sequence[str]] = ...
@@ -101,21 +121,21 @@ class ModelAdmin(BaseModelAdmin):
     list_max_show_all: int = ...
     list_editable: Sequence[str] = ...
     search_fields: Sequence[str] = ...
-    date_hierarchy: Optional[Any] = ...
+    date_hierarchy: Optional[str] = ...
     save_as: bool = ...
     save_as_continue: bool = ...
     save_on_top: bool = ...
-    paginator: Any = ...
+    paginator: Type = ...
     preserve_filters: bool = ...
     inlines: Sequence[Type[InlineModelAdmin]] = ...
-    add_form_template: Any = ...
+    add_form_template: str = ...
-    change_form_template: Any = ...
+    change_form_template: str = ...
-    change_list_template: Any = ...
+    change_list_template: str = ...
-    delete_confirmation_template: Any = ...
+    delete_confirmation_template: str = ...
-    delete_selected_confirmation_template: Any = ...
+    delete_selected_confirmation_template: str = ...
-    object_history_template: Any = ...
+    object_history_template: str = ...
-    popup_response_template: Any = ...
+    popup_response_template: str = ...
-    actions: Any = ...
+    actions: Sequence[Callable[[ModelAdmin, HttpRequest, QuerySet], None]] = ...
     action_form: Any = ...
     actions_on_top: bool = ...
     actions_on_bottom: bool = ...
@@ -227,9 +247,9 @@ class ModelAdmin(BaseModelAdmin):
     def history_view(self, request: HttpRequest, object_id: str, extra_context: None = ...) -> HttpResponse: ...
 
 class InlineModelAdmin(BaseModelAdmin):
-    model: Any = ...
+    model: Type[Model] = ...
-    fk_name: Any = ...
+    fk_name: str = ...
-    formset: Any = ...
+    formset: BaseFormSet = ...
     extra: int = ...
     min_num: Optional[int] = ...
     max_num: Optional[int] = ...
@@ -238,8 +258,8 @@ class InlineModelAdmin(BaseModelAdmin):
     verbose_name_plural: Optional[str] = ...
     can_delete: bool = ...
     show_change_link: bool = ...
-    classes: Any = ...
+    classes: Optional[Sequence[str]] = ...
-    admin_site: Any = ...
+    admin_site: AdminSite = ...
     parent_model: Any = ...
     opts: Any = ...
     has_registered_model: Any = ...

test-data/typecheck/contrib/admin/test_options.yml

@@ -0,0 +1,126 @@
+# "Happy path" test for model admin, trying to cover as many valid
+# configurations as possible.
+-   case: test_full_admin
+    main: |
+      from django.contrib import admin
+      from django.forms import Form, Textarea
+      from django.db import models
+      from django.core.paginator import Paginator
+      from django.contrib.admin.sites import AdminSite
+      from django.db.models.options import Options
+      from django.http.request import HttpRequest
+      from django.db.models.query import QuerySet
+
+      def an_action(modeladmin: admin.ModelAdmin, request: HttpRequest, queryset: QuerySet) -> None:
+          pass
+
+      class A(admin.ModelAdmin):
+          # BaseModelAdmin
+          autocomplete_fields = ("strs",)
+          raw_id_fields = ["strs"]
+          fields = (
+              "a field",
+              ["a", "list of", "fields"],
+          )
+          exclude = ("a", "b")
+          fieldsets = [
+              (None, {"fields": ["a", "b"]}),
+              ("group", {"fields": ("c",), "classes": ("a",), "description": "foo"}),
+          ]
+          form = Form
+          filter_vertical = ("fields",)
+          filter_horizontal = ("plenty", "of", "fields")
+          radio_fields = {
+              "some_field": admin.VERTICAL,
+              "another_field": admin.HORIZONTAL,
+          }
+          prepopulated_fields = {"slug": ("title",)}
+          formfield_overrides = {models.TextField: {"widget": Textarea}}
+          readonly_fields = ("date_modified",)
+          ordering = ("-pk", "date_modified")
+          sortable_by = ["pk"]
+          view_on_site = True
+          show_full_result_count = False
+
+          # ModelAdmin
+          list_display = ("pk",)
+          list_display_links = ("str",)
+          list_filter = ("str", admin.SimpleListFilter, ("str", admin.SimpleListFilter))
+          list_select_related = True
+          list_per_page = 1
+          list_max_show_all = 2
+          list_editable = ("a", "b")
+          search_fields = ("c", "d")
+          date_hirearchy = "f"
+          save_as = False
+          save_as_continue = True
+          save_on_top = False
+          paginator = Paginator
+          presserve_filters = False
+          inlines = (admin.TabularInline, admin.StackedInline)
+          add_form_template = "template"
+          change_form_template = "template"
+          change_list_template = "template"
+          delete_confirmation_template = "template"
+          delete_selected_confirmation_template = "template"
+          object_history_template = "template"
+          popup_response_template = "template"
+          actions = (an_action,)
+          actions_on_top = True
+          actions_on_bottom = False
+          actions_selection_counter = True
+          admin_site = AdminSite()
+# This test is here to make sure we're not running into a mypy issue which is
+# worked around using a somewhat complicated _ListOrTuple union type. Once the
+# issue is solved upstream this test should pass even with the workaround
+# replaced by a simpler Sequence type.
+# https://github.com/python/mypy/issues/8921
+-   case: test_fieldset_workaround_regression
+    main: |
+      from django.contrib import admin
+
+      class A(admin.ModelAdmin):
+          fieldsets = (
+              (None, {
+                  'fields': ('name',),
+              }),
+          )
+-   case: errors_on_omitting_fields_from_fieldset_opts
+    main: |
+      from django.contrib import admin
+
+      class A(admin.ModelAdmin):
+          fieldsets = [  # type: ignore
+              (None, {}),  # E: Key 'fields' missing for TypedDict "_FieldOpts"
+          ]
+-   case: errors_on_invalid_radio_fields
+    main: |
+      from django.contrib import admin
+
+      class A(admin.ModelAdmin):
+          radio_fields = {"some_field": 0}  # E: Dict entry 0 has incompatible type "str": "Literal[0]"; expected "str": "Union[Literal[1], Literal[2]]"
+
+      class B(admin.ModelAdmin):
+          radio_fields = {1: admin.VERTICAL}  # E: Dict entry 0 has incompatible type "int": "Literal[2]"; expected "str": "Union[Literal[1], Literal[2]]"
+-   case: errors_for_invalid_formfield_overrides
+    main: |
+      from django.contrib import admin
+      from django.forms import Textarea
+
+      class A(admin.ModelAdmin):
+          formfield_overrides = {
+              "not a field": {  # E: Dict entry 0 has incompatible type "str": "Dict[str, Any]"; expected "Type[Field[Any, Any]]": "Mapping[str, Any]"
+                  "widget": Textarea
+              }
+          }
+-   case: errors_for_invalid_action_signature
+    main: |
+      from django.contrib import admin
+      from django.http.request import HttpRequest
+      from django.db.models.query import QuerySet
+
+      def an_action(modeladmin: None) -> None:
+          pass
+
+      class A(admin.ModelAdmin):
+          actions = [an_action]  # E: List item 0 has incompatible type "Callable[[None], None]"; expected "Callable[[ModelAdmin, HttpRequest, QuerySet[Any]], None]"