本文将讲解自动测试。

第一个测试

Question.was_published_recently() 在问题发布时间为将来的时候，也会返回True，这是一个bug。

修改polls/tests.py文件如下：

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 the future.
        """
        time = timezone.now() + datetime.timedelta(days=30)
        future_question = Question(pub_date=time)
        self.assertIs(future_question.was_published_recently(), False)

测试系统将自动从所有文件中查找方法名以test开头的方法，然后执行。

在Terminal中执行：

py manage.py test polls

将显示：

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)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/path/to/mysite/polls/tests.py", line 16, 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'...

修改polls/models.py如下：

def was_published_recently(self):
    now = timezone.now()
    return now - datetime.timedelta(days=1) <= self.pub_date <= now

再次执行py manage.py test polls，将显示测试通过。

参考：https://docs.djangoproject.com/en/2.1/intro/tutorial05/