《python web开发 测试驱动方法》

第一部分 TDD和Django基础

第一章 使用功能测试协助安装Django

1.1 遵从测试山羊的教诲，没有测试什么也别做

• 先编写功能测试,建立文件functional_test.py

# -*- encoding: utf-8 -*-
from selenium import webdriver
browser = webdriver.Chrome()
browser.get("http://localhost:8000")
assert 'Django' in browser.title

• 会发现报错

1.2 让Django运行起来

• django-admin startproject superlists 创建项目

  C:\coding\python\tdd_learn\tdd_python_web\demo1>tree /f
  Folder PATH listing
  Volume serial number is 765E-FFBF
  C:.
  │ functional_tests.py
  │ geckodriver.log
  │
  └─superlists
  │ manage.py
  │
  └─superlists
  settings.py
  urls.py
  wsgi.py
  init.py

• 启动Django：python manage.py runserver

• 再开一个窗口，在其中再次尝试运行测试 python functional_tests.py

1.3 创建Git仓库

• mv functional_tests.py superlists/

• cd superlists/

• git init .

  $ ls
  db.sqlite3 functional_tests.py manage.py* superlists/
  db.sqlite3是数据库文件，不想把这个纳入版本控制，因此要将其添加到一个特殊的文件.gitignore中，告诉Git将其忽略

• echo "db.sqlite3" >> .gitignore

• git add .

• git status

• git rm -r --cached superlists/__pycache__/

• echo "__pycache__" >> .gitignore

• echo ".pyc" >> .gitignore

• git status

• git commit

• 在你自己的GitHub上建立一个仓库superlists,然后

  • git remote add origin https://github.com/Gin757306533/superlists.git

• git push -u origin master

• git push origin master

第2章 使用unittest模块扩展功能测试

2.1使用功能测试驱动开发一个最简可用的应用

2.2 python标准库中的unittest模块

• C:\coding\python\tdd_learn\tdd_python_web\demo1\superlists\functional_tests.py

# -*- encoding: utf-8 -*-
import unittest
from selenium import webdriver

class NewVisitorTest(unittest.TestCase):
    def setUp(self):
        self.browser = webdriver.Chrome()
        self.browser.implicitly_wait(3)
        # 隐式等待
    def tearDown(self):
        self.browser.quit()
    def test_can_start_a_list_and_retrieve_it_later(self):
        self.browser.get("http://localhost:8000")
        self.assertIn('To-Do' , self.browser.title)
        self.fail("Finish the test!")


if __name__ == '__main__':
    unittest.main(warnings='ignore')

2.3 隐式等待

2.4 提交

• git status
• git diff
• git commit -a

第3章 使用单元测试测试简单的首页

3.1 第一个Django应用，第一个单元测试

• python manage.py startapp lists

  C:\coding\python\tdd_learn\tdd_python_web\demo1\superlists>tree /F
  Folder PATH listing
  Volume serial number is 765E-FFBF
  C:.
  │ .gitignore
  │ db.sqlite3
  │ functional_tests.py
  │ manage.py
  │
  ├─lists
  │ │ admin.py
  │ │ apps.py
  │ │ models.py
  │ │ tests.py
  │ │ views.py
  │ │ init.py
  │ │
  │ └─migrations
  │ init.py
  │
  └─superlists
  │ settings.py
  │ urls.py
  │ wsgi.py
  │ init.py
  │
  └─pycache
  settings.cpython-36.pyc
  urls.cpython-36.pyc
  wsgi.cpython-36.pyc
  init.cpython-36.pyc

3.2 单元测试及其与功能测试的区别

• 功能测试站在用户的角度从外部测试应用
• 单元测试则站在程序员的角度从内部测试应用
• 工作流程
  • 先写功能测试
  • 功能测试失败后，想办法编写代码让它通过
    • 此时，使用一个或多个单元测试定义希望代码实现的效果，保证为应用中的每一行代码编写一个单元测试
  • 单元测试失败后，编写最少量的应用代码，刚好让单元测试通过。
  • 再次运行功能测试，看是否能够通过，或者有没有进展

3.3 Django中的单元测试

• django.test.TestCase是unittest.TestCase的增强版
• C:\coding\python\tdd_learn\tdd_python_web\demo1\superlists\lists\tests.py代码

from django.test import TestCase

# Create your tests here.
class SmokeTest(TestCase):
    def test_bad_maths(self):
        self.assertEqual(1+1, 3)

• 然后执行：python manage.py test，发现：

  Creating test database for alias 'default'...
  System check identified no issues (0 silenced).
  F

  FAIL: test_bad_maths (lists.tests.SmokeTest)

  Traceback (most recent call last):
  File "C:\coding\python\tdd_learn\tdd_python_web\demo1\superlists\lists\tests.py", line 6, in test_bad_maths
  self.assertEqual(1+1, 3)
  AssertionError: 2 != 3

  ---

  Ran 1 test in 0.002s

  FAILED (failures=1)
  Destroying test database for alias 'default'...

• git status

• git add lists

• git diff --staged

• git commit -m "Add app for lists, with deliberately failing unit test"

3.4 Django 中的MVC，URL和视图函数

• C:\coding\python\tdd_learn\tdd_python_web\demo1\superlists\lists\tests.py修改如下：

from django.test import TestCase
from django.urls import resolve
from lists.views import home_page
# Create your tests here.
class HomePageTest(TestCase):
    def test_root_url_resolves_to_home_page_view(self):
        found = resolve('/')
        self.assertEqual(found.func, home_page)
# class SmokeTest(TestCase):
#     def test_bad_maths(self):
#         self.assertEqual(1+1, 3)

• python manage.py test
  • 此时会报错，说无法导入home_page

3.5 终于可以编写一些应用代码了

• 上面无法导入home_page函数，所以可以这么做：
• C:\coding\python\tdd_learn\tdd_python_web\demo1\superlists\lists\views.py

from django.shortcuts import render

# Create your views here.
home_page = None

• 然后再执行：python manage.py test
  • 会报错，说无法解析"/"

3.6 urls.py

• C:\coding\python\Django_project\mysite\mysite\urls.py

"""superlists URL Configuration

The `urlpatterns` list routes URLs to views. For more information please see:
    https://docs.djangoproject.com/en/2.2/topics/http/urls/
Examples:
Function views
    1. Add an import:  from my_app import views
    2. Add a URL to urlpatterns:  path('', views.home, name='home')
Class-based views
    1. Add an import:  from other_app.views import Home
    2. Add a URL to urlpatterns:  path('', Home.as_view(), name='home')
Including another URLconf
    1. Import the include() function: from django.urls import include, path
    2. Add a URL to urlpatterns:  path('blog/', include('blog.urls'))
"""
from django.contrib import admin
from django.urls import path, re_path
from lists.views import home_page
urlpatterns = [
    path('admin/', admin.site.urls),
    re_path(r'^$', home_page)
]

• 然后执行，发现home_page不可调用
• 再改：C:\coding\python\tdd_learn\tdd_python_web\demo1\superlists\lists\views.py

from django.shortcuts import render

# Create your views here.
def home_page():
    pass

• 这次就会通过啦
• git diff
• git commit -am "First unit test and url mapping, dummy view"

3.7 为视图编写单元测试

• C:\coding\python\tdd_learn\tdd_python_web\demo1\superlists\lists\tests.py

from django.test import TestCase
from django.urls import resolve
from lists.views import home_page
from django.http import HttpRequest
# Create your tests here.
class HomePageTest(TestCase):
    def test_root_url_resolves_to_home_page_view(self):
        found = resolve('/')
        self.assertEqual(found.func, home_page)

    def test_home_page_returns_correct_html(self):
        request = HttpRequest()
        response = home_page(request)
        self.assertTrue(response.content.startswith(b'<html>'))
        self.assertIn(b'<title>To-Do lists</title>', response.content)
        self.assertTrue(response.content.endswith(b"</html>"))
# class SmokeTest(TestCase):
#     def test_bad_maths(self):
#         self.assertEqual(1+1, 3)

• C:\coding\python\tdd_learn\tdd_python_web\demo1\superlists\lists\views.py

from django.shortcuts import render
from django.http import HttpResponse
# Create your views here.
def home_page(request):
    return HttpResponse('<html><title>To-Do lists</title></html>')

• git diff
• git commit -am "Basic view now returns minimal HTML"

第4章 编写这些测试有什么用

4.1 编程就像从井里面打水

4.2 使用Selenium 测试用户交互

• python