Add some tests for the debug web backend

In part so that this has some CI coverage to highlight incompatibilities
with new versions of Django.

Author: PeterJCLaw

tests/settings.py

@@ -5,3 +5,7 @@
 INSTALLED_APPS = [
     'django_lightweight_queue',
 ]
+
+ROOT_URLCONF = 'tests.urls'
+
+SITE_URL = 'http://localhost:8000'

tests/test_debug_web_backend.py

@@ -0,0 +1,45 @@
+import io
+import unittest
+import contextlib
+import urllib.parse
+from unittest import mock
+
+from django.http import QueryDict
+from django.urls import resolve
+
+from django_lightweight_queue import task
+from django_lightweight_queue.job import Job
+from django_lightweight_queue.types import QueueName
+from django_lightweight_queue.backends.debug_web import DebugWebBackend
+
+
+@task()
+def demo_task() -> None:
+    pass
+
+
+class DebugWebBackendTests(unittest.TestCase):
+    def test_enqueue_prints_valid_url(self) -> None:
+        backend = DebugWebBackend()
+
+        job = Job('tests.test_debug_web_backend.demo_task', ('positional',), {'keyword': '&arg='})
+
+        with mock.patch('tests.test_debug_web_backend.demo_task') as demo_task_mock:
+            with contextlib.redirect_stdout(io.StringIO()) as mock_stdout:
+                backend.enqueue(job, QueueName('test-queue'))
+
+        url = mock_stdout.getvalue().strip()
+        parse_result = urllib.parse.urlparse(url)
+
+        match = resolve(parse_result.path)
+        self.assertIsNotNone(match, f"Failed to match {parse_result.path}")
+
+        query = QueryDict(parse_result.query)
+
+        self.assertEqual(
+            {'job': [job.to_json()]},
+            dict(query),
+            "Wrong query arguments printed",
+        )
+
+        demo_task_mock.assert_not_called()

tests/urls.py

@@ -0,0 +1,5 @@
+from django.urls import path, include
+
+urlpatterns = [
+    path('', include('django_lightweight_queue.urls', namespace='django-lightweight-queue')),
+]