1、介绍自动化测试
测试的主要工作是检查代码的运行情况。测试有全覆盖和部分覆盖。
自动测试表示测试工作由系统自动完成。
在大型系统中，有许多组件有很复杂的交互。一个小的变化可能会带来意想不到的后果
测试能发现问题，并以此解决问题。
测试驱动开发
在polls/tests.py文件中，建立 测试方法：
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)
在终端中输入以下命令，对投票系统进行测试：
python manage.py test polls
则输出以下信息。
表明系统有bug，测试失败。
修改文件polls/models.py为：
def was_published_recently(self):
now = timezone.now()
return now - datetime.timedelta(days=1) <= self.pub_date <= now
重新测试，则bug消失。
更复杂的测试
在测试文件中输入更多的测试方法：
def test_was_published_recently_with_old_question(self):
"""
was_published_recently() returns False for questions whose pub_date
is older than 1 day.
"""
time = timezone.now() - datetime.timedelta(days=1, seconds=1)
old_question = Question(pub_date=time)
self.assertIs(old_question.was_published_recently(), False)
def test_was_published_recently_with_recent_question(self):
"""
was_published_recently() returns True for questions whose pub_date
is within the last day.
"""
time = timezone.now() - datetime.timedelta(hours=23, minutes=59, seconds=59)
recent_question = Question(pub_date=time)
self.assertIs(recent_question.was_published_recently(), True)
现在有三个测试方法，分别对应于过去、最近和未来的问题。
可以在客户端建立测试环境来对网页进行测试。
在命令提示符下输入：
python manage.py shell
from django.test.utils import setup_test_environment
setup_test_environment()
导入客户端
from django.test import Client
建立一个客户端实例对象
client = Client()
修改polls/tests.py文件：
from django.urls import reverse
添加以下内容：
def create_question(question_text, days):
"""
Create a question with the given `question_text` and published the
given number of `days` offset to now (negative for questions published
in the past, positive for questions that have yet to be published).
"""
time = timezone.now() + datetime.timedelta(days=days)
return Question.objects.create(question_text=question_text, pub_date=time)
class QuestionIndexViewTests(TestCase):
def test_no_questions(self):
"""
If no questions exist, an appropriate message is displayed.
"""
response = self.client.get(reverse("polls:index"))
self.assertEqual(response.status_code, 200)
self.assertContains(response, "No polls are available.")
self.assertQuerySetEqual(response.context["latest_question_list"], [])
def test_past_question(self):
"""
Questions with a pub_date in the past are displayed on the
index page.
"""
question = create_question(question_text="Past question.", days=-30)
response = self.client.get(reverse("polls:index"))
self.assertQuerySetEqual(
response.context["latest_question_list"],
question\], ) def test_future_question(self): """ Questions with a pub_date in the future aren't displayed on the index page. """ create_question(question_text="Future question.", days=30) response = self.client.get(reverse("polls:index")) self.assertContains(response, "No polls are available.") self.assertQuerySetEqual(response.context\["latest_question_list"\], \[\]) def test_future_question_and_past_question(self): """ Even if both past and future questions exist, only past questions are displayed. """ question = create_question(question_text="Past question.", days=-30) create_question(question_text="Future question.", days=30) response = self.client.get(reverse("polls:index")) self.assertQuerySetEqual( response.context\["latest_question_list"\], \[question\], ) def test_two_past_questions(self): """ The questions index page may display multiple questions. """ question1 = create_question(question_text="Past question 1.", days=-30) question2 = create_question(question_text="Past question 2.", days=-5) response = self.client.get(reverse("polls:index")) self.assertQuerySetEqual( response.context\["latest_question_list"\], \[question2, question1\], ) 在polls/views.py中，添加以下内容： class DetailView(generic.DetailView): ... def get_queryset(self): """ Excludes any questions that aren't published yet. """ return Question.objects.filter(pub_date__lte=timezone.now()) 在polls/tests.py中，添加以下的内容： class QuestionDetailViewTests(TestCase): def test_future_question(self): """ The detail view of a question with a pub_date in the future returns a 404 not found. """ future_question = create_question(question_text="Future question.", days=5) url = reverse("polls:detail", args=(future_question.id,)) response = self.client.get(url) self.assertEqual(response.status_code, 404) def test_past_question(self): """ The detail view of a question with a pub_date in the past displays the question's text. """ past_question = create_question(question_text="Past Question.", days=-5) url = reverse("polls:detail", args=(past_question.id,)) response = self.client.get(url) self.assertContains(response, past_question.question_text) 错误更改`：如果使用self.assertQuerySetEqual` 收到一条错误消息"`DeviceTest object has no attribute assertQuerySetEqual`" 应将`assertQuerySetEqual` 替换为：assertEqual