Add description_plural to admin action decorator

django/contrib/admin/actions.py

@@ -7,6 +7,7 @@ from django.contrib.admin import helpers
 from django.contrib.admin.decorators import action
 from django.contrib.admin.utils import model_ngettext
 from django.core.exceptions import PermissionDenied
+from django.db.models.query import QuerySet
 from django.template.response import TemplateResponse
 from django.utils.translation import gettext as _
 from django.utils.translation import gettext_lazy
@@ -14,7 +15,8 @@ from django.utils.translation import gettext_lazy
 
 @action(
     permissions=["delete"],
-    description=gettext_lazy("Delete selected %(verbose_name_plural)s"),
+    description="Delete",
+    description_plural=gettext_lazy("Delete selected %(verbose_name_plural)s"),
 )
 def delete_selected(modeladmin, request, queryset):
     """
@@ -29,6 +31,11 @@ def delete_selected(modeladmin, request, queryset):
     opts = modeladmin.model._meta
     app_label = opts.app_label
 
+    # Handle the case when delete action is called from change view and
+    # it is a single object
+    if not isinstance(queryset, QuerySet):
+        queryset = modeladmin.model.objects.filter(id=queryset.id)
+
     # Populate deletable_objects, a data structure of all related objects that
     # will also be deleted.
     (

django/contrib/admin/decorators.py

@@ -1,10 +1,13 @@
-def action(function=None, *, permissions=None, description=None):
+def action(
+    function=None, *, permissions=None, description=None, description_plural=None
+):
     """
     Conveniently add attributes to an action function::
 
         @admin.action(
             permissions=['publish'],
-            description='Mark selected stories as published',
+            description='Mark story as published',
+            description_plural='Mark selected stories as published',
         )
         def make_published(self, request, queryset):
             queryset.update(status='p')
@@ -15,7 +18,8 @@ def action(function=None, *, permissions=None, description=None):
         def make_published(self, request, queryset):
             queryset.update(status='p')
         make_published.allowed_permissions = ['publish']
-        make_published.short_description = 'Mark selected stories as published'
+        make_published.short_description = 'Mark story as published'
+        make_published.plural_description = 'Mark selected stories as published'
     """
 
     def decorator(func):
@@ -23,6 +27,11 @@ def action(function=None, *, permissions=None, description=None):
             func.allowed_permissions = permissions
         if description is not None:
             func.short_description = description
+        if description_plural is not None:
+            func.plural_description = description_plural
+        elif description is not None:
+            func.plural_description = description
+
         return func
 
     if function is None:

django/contrib/admin/options.py

@@ -1032,16 +1032,21 @@ class ModelAdmin(BaseModelAdmin):
         return checkbox.render(helpers.ACTION_CHECKBOX_NAME, str(obj.pk))
 
     @staticmethod
-    def _get_action_description(func, name):
+    def _get_action_description(func, name, change=False):
         try:
-            return func.short_description
+            if change:
+                return func.short_description
+            else:
+                return func.plural_description
         except AttributeError:
             return capfirst(name.replace("_", " "))
 
-    def _get_base_actions(self):
+    def _get_base_actions(self, change=False):
         """Return the list of actions, prior to any request-based filtering."""
         actions = []
-        base_actions = (self.get_action(action) for action in self.actions or [])
+        base_actions = (
+            self.get_action(action, change) for action in self.actions or []
+        )
         # get_action might have returned None, so filter any of those out.
         base_actions = [action for action in base_actions if action]
         base_action_names = {name for _, name, _ in base_actions}
@@ -1050,7 +1055,7 @@ class ModelAdmin(BaseModelAdmin):
         for name, func in self.admin_site.actions:
             if name in base_action_names:
                 continue
-            description = self._get_action_description(func, name)
+            description = self._get_action_description(func, name, change)
             actions.append((func, name, description))
         # Add actions from this ModelAdmin.
         actions.extend(base_actions)
@@ -1072,7 +1077,7 @@ class ModelAdmin(BaseModelAdmin):
                 filtered_actions.append(action)
         return filtered_actions
 
-    def get_actions(self, request):
+    def get_actions(self, request, change=False):
         """
         Return a dictionary mapping the names of all actions for this
         ModelAdmin to a tuple of (callable, name, description) for each action.
@@ -1081,21 +1086,25 @@ class ModelAdmin(BaseModelAdmin):
         # this page.
         if self.actions is None or IS_POPUP_VAR in request.GET:
             return {}
-        actions = self._filter_actions_by_permissions(request, self._get_base_actions())
+        actions = self._filter_actions_by_permissions(
+            request, self._get_base_actions(change)
+        )
         return {name: (func, name, desc) for func, name, desc in actions}
 
-    def get_action_choices(self, request, default_choices=models.BLANK_CHOICE_DASH):
+    def get_action_choices(
+        self, request, change=False, default_choices=models.BLANK_CHOICE_DASH
+    ):
         """
         Return a list of choices for use in a form object. Each choice is a
         tuple (name, description).
         """
         choices = [] + default_choices
-        for func, name, description in self.get_actions(request).values():
+        for func, name, description in self.get_actions(request, change).values():
             choice = (name, description % model_format_dict(self.opts))
             choices.append(choice)
         return choices
 
-    def get_action(self, action):
+    def get_action(self, action, change):
         """
         Return a given action from a parameter, which can either be a callable,
         or the name of a method on the ModelAdmin. Return is a tuple of
@@ -1119,7 +1128,7 @@ class ModelAdmin(BaseModelAdmin):
             except KeyError:
                 return None
 
-        description = self._get_action_description(func, action)
+        description = self._get_action_description(func, action, change)
         return func, action, description
 
     def get_list_display(self, request):
@@ -1948,11 +1957,9 @@ class ModelAdmin(BaseModelAdmin):
         # Build the action form and populate it with available actions.
         if actions and not add:
             action_form = self.action_form(auto_id=None)
-            action_choices = self.get_action_choices(request)
+            action_form.fields["action"].choices = self.get_action_choices(
-            # Remove "delete" action; change view already has a button for
+                request, change=True
-            # that action.
+            )
-            action_choices.pop(1)
-            action_form.fields["action"].choices = action_choices
             media += action_form.media
         else:
             action_form = None

tests/admin_views/admin.py

@@ -411,7 +411,10 @@ def redirect_to(modeladmin, request, selected):
     return HttpResponseRedirect("/some-where-else/")
 
 
-@admin.action(description="Download subscription")
+@admin.action(
+    description="Download subscription",
+    description_plural="Download selected subscriptions",
+)
 def download(modeladmin, request, selected):
     from django.db.models.query import QuerySet
 

tests/admin_views/test_actions.py

@@ -299,7 +299,7 @@ subscribers</option>
 <option value="redirect_to">Redirect to (Awesome action)</option>
 <option value="external_mail">External mail (Another awesome
 action)</option>
-<option value="download">Download subscription</option>
+<option value="download">Download selected subscriptions</option>
 <option value="no_perm">No permission to run</option>
 </select>""",
             html=True,
@@ -562,12 +562,8 @@ class AdminDetailActionsTest(TestCase):
 
     def test_available_detail_actions(self):
         """
-        - Action 1 has not description.
+        'Download' action with singular description and
-        - Action 2 has custom description.
+        'Delete' action present in dropdown.
-        - Action 3 ("Detail download") is not displayed because user does not
-          have permission.
-        - "Delete" action is not displayed in change view because already
-          exists a button for it.
         """
 
         response = self.client.get(
@@ -578,15 +574,40 @@ class AdminDetailActionsTest(TestCase):
             response,
             """<label>Action: <select name="action" required>
             <option value="" selected>---------</option>
+            <option value="delete_selected">Delete</option>
             <option value="redirect_to">Redirect to (Awesome action)</option>
-            <option value="external_mail">External mail (Another awesome
+            <option value="external_mail">External mail (Another awesome action)
-            action)</option>
+            </option>
             <option value="download">Download subscription</option>
             <option value="no_perm">No permission to run</option>
             </select>""",
             html=True,
         )
 
+    def test_available_list_actions(self):
+        """
+        'Download' action with plural description.
+        """
+
+        response = self.client.get(
+            reverse("admin:admin_views_externalsubscriber_changelist")
+        )
+
+        self.assertContains(
+            response,
+            """<label>Action: <select name="action" required>
+            <option value="" selected>---------</option>
+            <option value="delete_selected">Delete selected external subscribers
+            </option>
+            <option value="redirect_to">Redirect to (Awesome action)</option>
+            <option value="external_mail">External mail (Another awesome action)
+            </option>
+            <option value="download">Download selected subscriptions</option>
+            <option value="no_perm">No permission to run</option>
+            </select>""",
+            html=True,
+        )
+
     def test_detail_actions_are_not_present_in_add_view(self):
         """
         `add_view` inherits the same function as `change_view` but actions are
@@ -622,6 +643,7 @@ class AdminDetailActionsTest(TestCase):
         """
         Edit the Subscriber and then choose an action won't save the changes.
         """
+
         self.client.post(
             reverse("admin:admin_views_externalsubscriber_change", args=[self.s1.pk]),
             {
@@ -653,3 +675,24 @@ class AdminDetailActionsTest(TestCase):
             f"This is the content of the file written by {self.s1.name}".encode(),
         )
         self.assertEqual(response.status_code, 200)
+
+    def test_delete_action_in_detail_view(self):
+        response = self.client.post(
+            reverse("admin:admin_views_externalsubscriber_change", args=[self.s1.pk]),
+            {"action": "delete_selected"},
+        )
+        self.assertTrue(response.status_code, 200)
+        self.assertContains(
+            response,
+            "Are you sure you want to delete the selected external subscriber?",
+        )
+
+        response = self.client.post(
+            reverse("admin:admin_views_externalsubscriber_change", args=[self.s1.pk]),
+            {
+                "action": "delete_selected",
+                "post": "yes",
+            },
+        )
+        self.assertTrue(response.status_code, 200)
+        self.assertEqual(ExternalSubscriber.objects.count(), 0)