[Django]-Testing admin.ModelAdmin in django

As suggested in Udi’s answer, we can study Django’s own ModelAdmin tests, to determine the basic ingredients for a ModelAdmin test. Here’s a summary:

Basic ingredients

In addition to the Django TestCase stuff, the basic ingredients are:

1. An instance of AdminSite:

    from django.contrib.admin.sites import AdminSite
   

2. Your model class and corresponding ModelAdmin (sub)class:

    from my_app.models import MyModel
    from my_app.admin import MyModelAdmin
   

3. Optionally, depending on your needs, a (mock) request and/or form.

Recipe

The first two ingredients are required to create an instance of your (custom) ModelAdmin:

my_model_admin = MyModelAdmin(model=MyModel, admin_site=AdminSite())

Based on the ModelAdmin source, the default save_model implementation only requires an instance of your model, so it can be called, for example, as follows:

my_model_admin.save_model(obj=MyModel(), request=None, form=None, change=None)
# some test assertions here

It all depends on what your save_model does, and what you want to test.
Suppose your save_model checks user permissions, then you would need to provide a request (i.e. the third ingredient) with a valid user, in addition to the model instance:

from unittest.mock import Mock

...

my_user = User.objects.create(...)
my_model_admin.save_model(
    obj=MyModel(), request=Mock(user=my_user), form=None, change=None
)
# some test assertions here

Here we use unittest.mock.Mock to create a mock-request. Based on the Django test source, a minimal request consists of a Python object with a user attribute.
The user attribute may refer to a mock user, or an actual instance of your AUTH_USER_MODEL, depending on your needs. An alternative would be to use django.test.RequestFactory.

This basic approach applies to the other ModelAdmin methods as well.

You can specify custom modelform for modeladmin then simply test this modelform 😉

https://docs.djangoproject.com/en/1.8/ref/contrib/admin/#django.contrib.admin.ModelAdmin.form

forms

class SomeModelForm(forms.ModelForm):
    class Meta:
        model = SomeModel

admin

class SomeModelAdmin(admin.ModelAdmin):
    form = SomeModelForm


admin.site.register(SomeModel, SomeModelAdmin)

tests

class TestSomeModel(TestCase):
    def test_form(self):
        form = SomeModelForm(**kwargs)
        self.assertTrue(form.is_valid())
        # ...

To test if the search does not lead to server errors (i.e. because search_fields are not correct) you can use the following code:

from django.contrib import admin
from django.contrib.auth.models import User
from django.test import TestCase
from django.urls import reverse


class TestModelAdmins(TestCase):
    def test_search_fields(self):
        user_1 = User(
            username="user1",
            first_name="User",
            last_name="One",
            email="user1@example.org",
            password="superSecurePasswordFromStackoverflow",
            is_superuser=True,
            is_staff=True,
        )
        user_1.full_clean()
        user_1.save()
        self.client.force_login(user_1)
        for model_class, admin_class in admin.site._registry.items():
            with self.subTest(model_class._meta.model_name):
                path = reverse("admin:%s_%s_changelist" % (model_class._meta.app_label, model_class._meta.model_name))
                response = self.client.get(path + "?q=blub")
                self.assertEqual(response.status_code, 200)