Fixed #14370 -- Allowed using a Select2 widget for ForeignKey and ManyToManyField in the admin.

Thanks Florian Apolloner and Tim Graham for review and
contributing to the patch.

1 files changed, 231 insertions, 0 deletions

diff --git a/tests/admin_views/test_autocomplete_view.py b/tests/admin_views/test_autocomplete_view.py
new file mode 100644
index 0000000000..8396ceb5d1
--- /dev/null
+++ b/tests/admin_views/test_autocomplete_view.py
@@ -0,0 +1,231 @@
+import json
+
+from django.contrib import admin
+from django.contrib.admin import site
+from django.contrib.admin.tests import AdminSeleniumTestCase
+from django.contrib.admin.views.autocomplete import AutocompleteJsonView
+from django.contrib.auth.models import Permission, User
+from django.contrib.contenttypes.models import ContentType
+from django.http import Http404
+from django.test import RequestFactory, override_settings
+from django.urls import reverse, reverse_lazy
+
+from .admin import AnswerAdmin, QuestionAdmin
+from .models import Answer, Author, Authorship, Book, Question
+from .tests import AdminViewBasicTestCase
+
+PAGINATOR_SIZE = AutocompleteJsonView.paginate_by
+
+
+class AuthorAdmin(admin.ModelAdmin):
+    search_fields = ['id']
+
+
+class AuthorshipInline(admin.TabularInline):
+    model = Authorship
+    autocomplete_fields = ['author']
+
+
+class BookAdmin(admin.ModelAdmin):
+    inlines = [AuthorshipInline]
+
+
+site.register(Question, QuestionAdmin)
+site.register(Answer, AnswerAdmin)
+site.register(Author, AuthorAdmin)
+site.register(Book, BookAdmin)
+
+
+class AutocompleteJsonViewTests(AdminViewBasicTestCase):
+    as_view_args = {'model_admin': QuestionAdmin(Question, site)}
+    factory = RequestFactory()
+    url = reverse_lazy('admin:admin_views_question_autocomplete')
+
+    @classmethod
+    def setUpTestData(cls):
+        cls.user = User.objects.create_user(
+            username='user', password='secret',
+            email='user@example.com', is_staff=True,
+        )
+        super().setUpTestData()
+
+    def test_success(self):
+        q = Question.objects.create(question='Is this a question?')
+        request = self.factory.get(self.url, {'term': 'is'})
+        request.user = self.superuser
+        response = AutocompleteJsonView.as_view(**self.as_view_args)(request)
+        self.assertEqual(response.status_code, 200)
+        data = json.loads(response.content.decode('utf-8'))
+        self.assertEqual(data, {
+            'results': [{'id': str(q.pk), 'text': q.question}],
+            'pagination': {'more': False},
+        })
+
+    def test_must_be_logged_in(self):
+        response = self.client.get(self.url, {'term': ''})
+        self.assertEqual(response.status_code, 200)
+        self.client.logout()
+        response = self.client.get(self.url, {'term': ''})
+        self.assertEqual(response.status_code, 302)
+
+    def test_has_change_permission_required(self):
+        """
+        Users require the change permission for the related model to the
+        autocomplete view for it.
+        """
+        request = self.factory.get(self.url, {'term': 'is'})
+        self.user.is_staff = True
+        self.user.save()
+        request.user = self.user
+        response = AutocompleteJsonView.as_view(**self.as_view_args)(request)
+        self.assertEqual(response.status_code, 403)
+        self.assertJSONEqual(response.content.decode('utf-8'), {'error': '403 Forbidden'})
+        # Add the change permission and retry.
+        p = Permission.objects.get(
+            content_type=ContentType.objects.get_for_model(Question),
+            codename='change_question',
+        )
+        self.user.user_permissions.add(p)
+        request.user = User.objects.get(pk=self.user.pk)
+        response = AutocompleteJsonView.as_view(**self.as_view_args)(request)
+        self.assertEqual(response.status_code, 200)
+
+    def test_search_use_distinct(self):
+        """
+        Searching across model relations use QuerySet.distinct() to avoid
+        duplicates.
+        """
+        q1 = Question.objects.create(question='question 1')
+        q2 = Question.objects.create(question='question 2')
+        q2.related_questions.add(q1)
+        q3 = Question.objects.create(question='question 3')
+        q3.related_questions.add(q1)
+        request = self.factory.get(self.url, {'term': 'question'})
+        request.user = self.superuser
+
+        class DistinctQuestionAdmin(QuestionAdmin):
+            search_fields = ['related_questions__question', 'question']
+
+        model_admin = DistinctQuestionAdmin(Question, site)
+        response = AutocompleteJsonView.as_view(model_admin=model_admin)(request)
+        self.assertEqual(response.status_code, 200)
+        data = json.loads(response.content.decode('utf-8'))
+        self.assertEqual(len(data['results']), 3)
+
+    def test_missing_search_fields(self):
+        class EmptySearchAdmin(QuestionAdmin):
+            search_fields = []
+
+        model_admin = EmptySearchAdmin(Question, site)
+        msg = 'EmptySearchAdmin must have search_fields for the autocomplete_view.'
+        with self.assertRaisesMessage(Http404, msg):
+            model_admin.autocomplete_view(self.factory.get(self.url))
+
+    def test_get_paginator(self):
+        """Search results are paginated."""
+        Question.objects.bulk_create(Question(question=str(i)) for i in range(PAGINATOR_SIZE + 10))
+        model_admin = QuestionAdmin(Question, site)
+        model_admin.ordering = ['pk']
+        # The first page of results.
+        request = self.factory.get(self.url, {'term': ''})
+        request.user = self.superuser
+        response = AutocompleteJsonView.as_view(model_admin=model_admin)(request)
+        self.assertEqual(response.status_code, 200)
+        data = json.loads(response.content.decode('utf-8'))
+        self.assertEqual(data, {
+            'results': [{'id': str(q.pk), 'text': q.question} for q in Question.objects.all()[:PAGINATOR_SIZE]],
+            'pagination': {'more': True},
+        })
+        # The second page of results.
+        request = self.factory.get(self.url, {'term': '', 'page': '2'})
+        request.user = self.superuser
+        response = AutocompleteJsonView.as_view(model_admin=model_admin)(request)
+        self.assertEqual(response.status_code, 200)
+        data = json.loads(response.content.decode('utf-8'))
+        self.assertEqual(data, {
+            'results': [{'id': str(q.pk), 'text': q.question} for q in Question.objects.all()[PAGINATOR_SIZE:]],
+            'pagination': {'more': False},
+        })
+
+
+@override_settings(ROOT_URLCONF='admin_views.urls')
+class SeleniumTests(AdminSeleniumTestCase):
+    available_apps = ['admin_views'] + AdminSeleniumTestCase.available_apps
+
+    def setUp(self):
+        self.superuser = User.objects.create_superuser(
+            username='super', password='secret', email='super@example.com',
+        )
+        self.admin_login(username='super', password='secret', login_url=reverse('admin:index'))
+
+    def test_select(self):
+        from selenium.webdriver.common.keys import Keys
+        from selenium.webdriver.support.ui import Select
+        self.selenium.get(self.live_server_url + reverse('admin:admin_views_answer_add'))
+        elem = self.selenium.find_element_by_css_selector('.select2-selection')
+        elem.click()  # Open the autocomplete dropdown.
+        results = self.selenium.find_element_by_css_selector('.select2-results')
+        self.assertTrue(results.is_displayed())
+        option = self.selenium.find_element_by_css_selector('.select2-results__option')
+        self.assertEqual(option.text, 'No results found')
+        elem.click()  # Close the autocomplete dropdown.
+        q1 = Question.objects.create(question='Who am I?')
+        Question.objects.bulk_create(Question(question=str(i)) for i in range(PAGINATOR_SIZE + 10))
+        elem.click()  # Reopen the dropdown now that some objects exist.
+        result_container = self.selenium.find_element_by_css_selector('.select2-results')
+        self.assertTrue(result_container.is_displayed())
+        results = result_container.find_elements_by_css_selector('.select2-results__option')
+        # PAGINATOR_SIZE results and "Loading more results".
+        self.assertEqual(len(results), PAGINATOR_SIZE + 1)
+        search = self.selenium.find_element_by_css_selector('.select2-search__field')
+        # Load next page of results by scrolling to the bottom of the list.
+        for _ in range(len(results)):
+            search.send_keys(Keys.ARROW_DOWN)
+        results = result_container.find_elements_by_css_selector('.select2-results__option')
+        # All objects and "Loading more results".
+        self.assertEqual(len(results), PAGINATOR_SIZE + 11)
+        # Limit the results with the search field.
+        search.send_keys('Who')
+        results = result_container.find_elements_by_css_selector('.select2-results__option')
+        self.assertEqual(len(results), 1)
+        # Select the result.
+        search.send_keys(Keys.RETURN)
+        select = Select(self.selenium.find_element_by_id('id_question'))
+        self.assertEqual(select.first_selected_option.get_attribute('value'), str(q1.pk))
+
+    def test_select_multiple(self):
+        from selenium.webdriver.common.keys import Keys
+        from selenium.webdriver.support.ui import Select
+        self.selenium.get(self.live_server_url + reverse('admin:admin_views_question_add'))
+        elem = self.selenium.find_element_by_css_selector('.select2-selection')
+        elem.click()  # Open the autocomplete dropdown.
+        results = self.selenium.find_element_by_css_selector('.select2-results')
+        self.assertTrue(results.is_displayed())
+        option = self.selenium.find_element_by_css_selector('.select2-results__option')
+        self.assertEqual(option.text, 'No results found')
+        elem.click()  # Close the autocomplete dropdown.
+        Question.objects.create(question='Who am I?')
+        Question.objects.bulk_create(Question(question=str(i)) for i in range(PAGINATOR_SIZE + 10))
+        elem.click()  # Reopen the dropdown now that some objects exist.
+        result_container = self.selenium.find_element_by_css_selector('.select2-results')
+        self.assertTrue(result_container.is_displayed())
+        results = result_container.find_elements_by_css_selector('.select2-results__option')
+        self.assertEqual(len(results), PAGINATOR_SIZE + 1)
+        search = self.selenium.find_element_by_css_selector('.select2-search__field')
+        # Load next page of results by scrolling to the bottom of the list.
+        for _ in range(len(results)):
+            search.send_keys(Keys.ARROW_DOWN)
+        results = result_container.find_elements_by_css_selector('.select2-results__option')
+        self.assertEqual(len(results), 31)
+        # Limit the results with the search field.
+        search.send_keys('Who')
+        results = result_container.find_elements_by_css_selector('.select2-results__option')
+        self.assertEqual(len(results), 1)
+        # Select the result.
+        search.send_keys(Keys.RETURN)
+        # Reopen the dropdown and add the first result to the selection.
+        elem.click()
+        search.send_keys(Keys.ARROW_DOWN)
+        search.send_keys(Keys.RETURN)
+        select = Select(self.selenium.find_element_by_id('id_related_questions'))
+        self.assertEqual(len(select.all_selected_options), 2)