Used model's Options.label/label_lower where applicable.

django/contrib/admin/checks.py

@@ -607,8 +607,9 @@ class BaseModelAdminChecks:
             except FieldDoesNotExist:
                 return [
                     checks.Error(
-                        "The value of '%s' is not a callable, an attribute of '%s', or an attribute of '%s.%s'." % (
-                            label, obj.__class__.__name__, obj.model._meta.app_label, obj.model._meta.object_name
+                        "The value of '%s' is not a callable, an attribute of "
+                        "'%s', or an attribute of '%s'." % (
+                            label, obj.__class__.__name__, obj.model._meta.label,
                         ),
                         obj=obj.__class__,
                         id='admin.E035',
@@ -731,9 +732,9 @@ class ModelAdminChecks(BaseModelAdminChecks):
                     checks.Error(
                         "The value of '%s' refers to '%s', which is not a "
                         "callable, an attribute of '%s', or an attribute or "
-                        "method on '%s.%s'." % (
+                        "method on '%s'." % (
                             label, item, obj.__class__.__name__,
-                            obj.model._meta.app_label, obj.model._meta.object_name,
+                            obj.model._meta.label,
                         ),
                         obj=obj.__class__,
                         id='admin.E108',
@@ -1035,8 +1036,8 @@ class InlineModelAdminChecks(BaseModelAdminChecks):
             return [
                 checks.Error(
                     "Cannot exclude the field '%s', because it is the foreign key "
-                    "to the parent model '%s.%s'." % (
-                        fk.name, parent_model._meta.app_label, parent_model._meta.object_name
+                    "to the parent model '%s'." % (
+                        fk.name, parent_model._meta.label,
                     ),
                     obj=obj.__class__,
                     id='admin.E201',
@@ -1113,9 +1114,8 @@ def must_inherit_from(parent, option, obj, id):
 def refer_to_missing_field(field, option, obj, id):
     return [
         checks.Error(
-            "The value of '%s' refers to '%s', which is not an attribute of '%s.%s'." % (
-                option, field, obj.model._meta.app_label, obj.model._meta.object_name
-            ),
+            "The value of '%s' refers to '%s', which is not an attribute of "
+            "'%s'." % (option, field, obj.model._meta.label),
             obj=obj.__class__,
             id=id,
         ),

django/contrib/admindocs/views.py

@@ -307,7 +307,7 @@ class ModelDetailView(BaseAdminDocsView):
             })
         return super().get_context_data(**{
             **kwargs,
-            'name': '%s.%s' % (opts.app_label, opts.object_name),
+            'name': opts.label,
             'summary': title,
             'description': body,
             'fields': fields,

django/contrib/auth/checks.py

@@ -119,9 +119,10 @@ def check_models_permissions(app_configs=None, **kwargs):
             )
             errors.append(
                 checks.Error(
-                    "The verbose_name of model '%s.%s' must be at most %d characters "
-                    "for its builtin permission names to be at most %d characters." % (
-                        opts.app_label, opts.object_name, verbose_name_max_length, permission_name_max_length
+                    "The verbose_name of model '%s' must be at most %d "
+                    "characters for its builtin permission names to be at "
+                    "most %d characters." % (
+                        opts.label, verbose_name_max_length, permission_name_max_length
                     ),
                     obj=model,
                     id='auth.E007',
@@ -138,11 +139,10 @@ def check_models_permissions(app_configs=None, **kwargs):
             )
             errors.append(
                 checks.Error(
-                    "The name of model '%s.%s' must be at most %d characters "
+                    "The name of model '%s' must be at most %d characters "
                     "for its builtin permission codenames to be at most %d "
                     "characters." % (
-                        opts.app_label,
-                        opts.object_name,
+                        opts.label,
                         model_name_max_length,
                         permission_codename_max_length,
                     ),
@@ -156,8 +156,9 @@ def check_models_permissions(app_configs=None, **kwargs):
             if len(name) > permission_name_max_length:
                 errors.append(
                     checks.Error(
-                        "The permission named '%s' of model '%s.%s' is longer than %d characters." % (
-                            name, opts.app_label, opts.object_name, permission_name_max_length
+                        "The permission named '%s' of model '%s' is longer "
+                        "than %d characters." % (
+                            name, opts.label, permission_name_max_length,
                         ),
                         obj=model,
                         id='auth.E008',
@@ -167,11 +168,10 @@ def check_models_permissions(app_configs=None, **kwargs):
             if len(codename) > permission_codename_max_length:
                 errors.append(
                     checks.Error(
-                        "The permission codenamed '%s' of model '%s.%s' is "
+                        "The permission codenamed '%s' of model '%s' is "
                         "longer than %d characters." % (
                             codename,
-                            opts.app_label,
-                            opts.object_name,
+                            opts.label,
                             permission_codename_max_length,
                         ),
                         obj=model,
@@ -183,9 +183,7 @@ def check_models_permissions(app_configs=None, **kwargs):
                 errors.append(
                     checks.Error(
                         "The permission codenamed '%s' clashes with a builtin permission "
-                        "for model '%s.%s'." % (
-                            codename, opts.app_label, opts.object_name
-                        ),
+                        "for model '%s'." % (codename, opts.label),
                         obj=model,
                         id='auth.E005',
                     )
@@ -193,9 +191,8 @@ def check_models_permissions(app_configs=None, **kwargs):
             elif codename in codenames:
                 errors.append(
                     checks.Error(
-                        "The permission codenamed '%s' is duplicated for model '%s.%s'." % (
-                            codename, opts.app_label, opts.object_name
-                        ),
+                        "The permission codenamed '%s' is duplicated for "
+                        "model '%s'." % (codename, opts.label),
                         obj=model,
                         id='auth.E006',
                     )

django/core/serializers/__init__.py

@@ -225,7 +225,7 @@ def sort_dependencies(app_list):
             raise RuntimeError(
                 "Can't resolve dependencies for %s in serialized app list." %
                 ', '.join(
-                    '%s.%s' % (model._meta.app_label, model._meta.object_name)
+                    model._meta.label
                     for model, deps in sorted(skipped, key=lambda obj: obj[0].__name__)
                 )
             )

django/db/models/options.py

@@ -307,7 +307,7 @@ class Options:
         return '<Options for %s>' % self.object_name
 
     def __str__(self):
-        return "%s.%s" % (self.app_label, self.model_name)
+        return self.label_lower
 
     def can_migrate(self, connection):
         """