5.1 First test

first_django_app.md

@@ -417,3 +417,73 @@ class ResultsView(generic.DetailView):
 * 我们提供 context_object_name 属性，表示我们想使用 latest_question_list
 
 重启服务器后，就是新的投票应用（同样的html），但是内部用了generic view
+
+## Part 5 Automated Test
+
+TDD with python. Always stick to it.
+
+### 5.1 First test
+
+#### Create/Verify a bug
+
+幸运的是，我们的 polls 应用现在就有一个小 bug 需要被修复：我们的要求是如果 Question 是在一天之内发布的， Question.was_published_recently() 方法将会返回 True ，然而现在这个方法在 Question 的 pub_date 字段比当前时间还晚时也会返回 True（这是个 Bug）。
+
+确认bug:
+
+```
+>>> import datetime
+>>> from django.utils import timezone
+>>> from polls.models import Question
+>>> # create a Question instance with pub_date 30 days in the future
+>>> future_question = Question(pub_date=timezone.now() + datetime.timedelta(days=30))
+>>> # was it published recently?
+>>> future_question.was_published_recently()
+True
+```
+
+#### Create a test to verify this bug
+
+All tests (polls/tests.py) are in app directory
+
+```python
+import datetime
+
+from django.test import TestCase
+from django.utils import timezone
+
+from .models import Question
+
+class QuestionModelTests(TestCase):
+
+    def test_was_published_recently_with_future_question(self):
+        """
+        was_published_recently() returns False for questions whose pub_date is in future
+        """
+
+        time = timezone.now() + datetime.timedelta(days=30)
+        future_question = Question(pub_date=time)
+        self.assertIs(future_question.was_published_recently(), False)
+```
+
+Result
+
+```
+python manage.py test polls
+Creating test database for alias 'default'...
+System check identified no issues (0 silenced).
+F
+======================================================================
+FAIL: test_was_published_recently_with_future_question (polls.tests.QuestionModelTests)
+was_published_recently() returns False for questions whose pub_date is in future
+----------------------------------------------------------------------
+Traceback (most recent call last):
+  File "/home/jason/HomeWorkstation/SynologyGiteaSpace/djangoproject/src/polls/tests.py", line 17, in test_was_published_recently_with_future_question
+    self.assertIs(future_question.was_published_recently(), False)
+AssertionError: True is not False
+
+----------------------------------------------------------------------
+Ran 1 test in 0.001s
+
+FAILED (failures=1)
+Destroying test database for alias 'default'...
+```

src/polls/tests.py

@@ -1,3 +1,17 @@
-from django.test import TestCase
+import datetime
 
-# Create your tests here.
+from django.test import TestCase
+from django.utils import timezone
+
+from .models import Question
+
+class QuestionModelTests(TestCase):
+
+    def test_was_published_recently_with_future_question(self):
+        """
+        was_published_recently() returns False for questions whose pub_date is in future
+        """
+
+        time = timezone.now() + datetime.timedelta(days=30)
+        future_question = Question(pub_date=time)
+        self.assertIs(future_question.was_published_recently(), False)