Fixed #26919 -- Added the action form's media in the changelist view.

django/contrib/admin/options.py

@@ -1642,6 +1642,7 @@ class ModelAdmin(BaseModelAdmin):
         if actions:
             action_form = self.action_form(auto_id=None)
             action_form.fields['action'].choices = self.get_action_choices(request)
+            media += action_form.media
         else:
             action_form = None
 

tests/admin_views/admin.py

@@ -22,6 +22,7 @@ from django.utils.html import format_html
 from django.utils.safestring import mark_safe
 from django.utils.six import StringIO
 
+from .forms import MediaActionForm
 from .models import (
     Actor, AdminOrderedAdminMethod, AdminOrderedCallable, AdminOrderedField,
     AdminOrderedModelMethod, Album, Answer, Article, BarAccount, Book,
@@ -235,6 +236,7 @@ class PersonaAdmin(admin.ModelAdmin):
 
 class SubscriberAdmin(admin.ModelAdmin):
     actions = ['mail_admin']
+    action_form = MediaActionForm
 
     def mail_admin(self, request, selected):
         EmailMessage(

tests/admin_views/forms.py

 from django import forms
 from django.contrib.admin.forms import AdminAuthenticationForm
+from django.contrib.admin.helpers import ActionForm
 
 
 class CustomAdminAuthenticationForm(AdminAuthenticationForm):
@@ -12,3 +13,8 @@ class CustomAdminAuthenticationForm(AdminAuthenticationForm):
         if username == 'customform':
             raise forms.ValidationError('custom form error')
         return username
+
+
+class MediaActionForm(ActionForm):
+    class Media:
+        js = ['path/to/media.js']

tests/admin_views/tests.py

@@ -43,6 +43,7 @@ from django.utils.six.moves.urllib.parse import parse_qsl, urljoin, urlparse
 
 from . import customadmin
 from .admin import CityAdmin, site, site2
+from .forms import MediaActionForm
 from .models import (
     Actor, AdminOrderedAdminMethod, AdminOrderedCallable, AdminOrderedField,
     AdminOrderedModelMethod, Answer, Article, BarAccount, Book, Bookmark,
@@ -3374,6 +3375,17 @@ action)</option>
         self.assertEqual(len(mail.outbox), 1)
         self.assertEqual(mail.outbox[0].subject, 'Greetings from a function action')
 
+    def test_media_from_actions_form(self):
+        """
+        The action form's media is included in changelist view's media.
+        """
+        response = self.client.get(reverse('admin:admin_views_subscriber_changelist'))
+        media_path = MediaActionForm.Media.js[0]
+        self.assertIsInstance(response.context['action_form'], MediaActionForm)
+        self.assertIn('media', response.context)
+        self.assertIn(media_path, response.context['media']._js)
+        self.assertContains(response, media_path)
+
     def test_user_message_on_none_selected(self):
         """
         User should see a warning when 'Go' is pressed and no items are selected.