[test development] automated test selenium (III) -- unittest framework analysis

unittest Framework analysis

unittest yes python The unit test framework of , stay python In the official documents of , Yes unittest There is a detailed introduction , Students who want to further study can go to https://www.python.org/doc/ To understand .

unittest Unit testing provides the ability to create test cases , Test suite and batch execution scheme , unittest In the installation pyhton I'll bring it myself , direct import unittest You can use .

As a framework for unit testing , unittest It is also an agile test of the smallest module of the program . In automated testing , We don't need to do a white box test , But you need to know the unit test framework of the language you use . Using unit test framework , Create a class , Inheritance of such kind unittest Of TestCase, So that we can case As a minimum unit , Organized by test containers , When the time comes, execute directly , At the same time, the test report is introduced .

unittest The relationship of each component is ：

• test fixture： Test firmware , Initialize and clean up the test environment , Like creating a temporary database , Files and directories, etc , among setUp() and setDown() Is the most commonly used method
• test case： Unit Test Case ,TestCase It is the most commonly used class for writing unit test cases
• test suite： test suite , A collection of unit test cases ,TestSuite Is the most commonly used class
• test runner： Perform unit tests
• test report： Generate test reports

unittest and Junit The difference between

Testing firmware is simple ：

import time
from selenium import webdriver
import unittest


class Test(unittest.TestCase):
    # Test Inherited from unittest.TestCase
    #  Test firmware  setup and tearDown
    #  there self It is equivalent to an example 
    def setUp(self):
        self.driver = webdriver.Chrome()
        self.url = "http://www.baidu.com/"
        self.driver.maximize_window()

    def tearDown(self):
        self.driver.quit()

    #  The test method name must be test_ Otherwise, it will not be carried out 
    def test_baidu(self):
        driver = self.driver
        driver.get(self.url)
        driver.find_element_by_id("kw").send_keys("kobe")
        driver.find_element_by_id("su").click()
        time.sleep(3)

    if __name__ == "__main__":
        unittest.main(2)
'''  Can increase verbosity Parameters , for example unittest.main(verbosity=2)  In the main function , Call directly main() , stay main Add verbosity=2 , In this way, the test results will be displayed in more detail .  there verbosity  It's an option ,  Represents the information complexity of the test results , There are three values : 0 (  silent mode ):  You can only get the total number of test cases and total results, such as a total of 100 A failure ,20  success 80 1 (  The default mode ):  It's very similar to the silent mode, except that there is a... In front of each successful use case “ . ”  Each failed use case is preceded by a “F” 2 (  Detailed mode ):  The test results show all the relevant information for each test case  '''

Batch script execution

Build test suite

Complete unit tests rarely execute only one test case , Developers usually need to write multiple test cases to test a software function completely , These related test cases are called a test case set , stay unittest Medium used TestSuite Class .

Suppose we have written testbaidu1.py,testbaidu2.py Two documents , So how can we execute these two files at the same time ？

addTest（） Application

When there are multiple or hundreds of test cases , This requires a test container ( test suite ) , Put the test case in the container for execution ,unittest Module provides TestSuite Class to generate the test suite , Using the constructor of this class, you can generate an instance of the test suite , This class provides addTest To add each test case to the test suite .
take testbaidu1.py、testbaidu2.py、runall.py Put it in the same directory testcase in

runall.py The contents are as follows

import time
#  Import test_baidu1,test_baidu2
import test_baidu1
import test_baidu2
import unittest


#  Manually add cases to the suite ,
def createsuite():
    suite = unittest.TestSuite()
    #  Add test cases to the test container （ Kit ） in 
    suite.addTest(test_baidu1.Baidu1("test_baidu1"))
    suite.addTest(test_baidu2.Baidu2("test_baidu2"))
    return suite


if __name__ == "__main__":
    suite = createsuite()
    runner = unittest.TextTestRunner(verbosity=2)
    runner.run(suite)

There are two aspects of the above approach , Hinder the rapid execution of scripts , Must be modified every time runall.py：
1） You need to import all py file , such as import testbaidu1, Each new one needs to be imported
2）addTest Need to add all testcase, If one py In file 10 individual case, It needs to be increased 10 Time

makeSuite（） and TestLoader() Application

stay unittest The framework provides makeSuite() Methods ,makeSuite It can realize all the tests in the test case class case Test suite composed of TestSuite ,unittest call makeSuite When , Just pass in the test class name .

TestLoader Test suite for creating classes and modules
In general , send TestLoader().loadTestsFromTestCase(TestClass) To load the test class .

runall.py The contents are as follows

import time
#  Import test_baidu1,test_baidu2
import test_baidu1
import test_baidu2
import unittest


#  Manually add cases to the suite ,

def createsuite():
 suite = unittest.TestSuite()
 #  Add test cases to the test container （ Kit ） in 
 suite.addTest(unittest.makeSuite(test_baidu1.Baidu1))
 suite.addTest(unittest.makeSuite(test_baidu2.Baidu2))
 return suite
''' suite1 = unittest.TestLoader().loadTestsFromTestCase(test_baidu1.Baidu1) suite2 = unittest.TestLoader().loadTestsFromTestCase(test_baidu2.Baidu2) suite = unittest.TestSuite([suite1, suite2]) return suite '''
if __name__ == "__main__":
    suite = createsuite()
    runner = unittest.TextTestRunner(verbosity=2)
    runner.run(suite)

after makeSuite（） and TestLoader（） The introduction of , We don't need one py File test class , You only need to import it once .

So can you test classes without adding specifications every time ？

discover（） Application

discover Is recursively to its subdirectory, starting from the specified directory , Find all test modules and return an object containing them TestSuite , Then load the only test file matching the pattern ,discover The parameters are
discover(dir,pattern,top_level_dir=None)

runall.py— Pay attention to the path

# -*- coding: utf-8 -*-
import unittest,csv
import os,sys
import time
# Manually add cases to the suite ,
def createsuite():
 
discover=unittest.defaultTestLoader.discover('../test',pattern='test*.py',top_level_dir=None)
 print discover
 return discover
 
if __name__=="__main__":
 suite=createsuite()
 runner = unittest.TextTestRunner(verbosity=2)
 runner.run(suite)

Use case execution sequence

unittest By default, the order in which the framework loads test cases is based on ASCII The order of the codes , The order of numbers and letters is ： 0_9,AZ,a~z

therefore , TestAdd Class will take precedence over TestBdd Class is found , test_aaa() Method will take precedence over test_ccc() Be performed .

For test directories and test files , unittest The framework also loads test cases according to this rule .
addTest（） Methods are executed in increasing order .

Ignore use case execution

@unittest.skip("skipping")
Adding this comment before the test method is to ignore the use case execution

unittest Assertion

Automated testing , For each individual case Come on , One case In the execution result of , There must be expected results and actual results , To judge the right case Pass or fail , stay unittest The library provides a number of practical ways to check expected and actual values , To verify case Result , Generally speaking , The inspection conditions are roughly divided into equivalence , Logical comparison and other , If the given assertion passes , The test will continue to the next line of code , If the assertion fails , Corresponding case The test will stop immediately or generate an error message ( Generally, you can print error messages ) , But don't affect others case perform .

unittest The unit test library provides a standard xUnit assert methods . Here are some common assertions

Serial number	assert methods	Assertion description
1	assertEqual(arg1, arg2, msg=None)	verification arg1=arg2, If you don't wait fail
2	assertNotEqual(arg1, arg2, msg=None)	verification arg1 != arg2, Equal is equal fail
3	assertTrue(expr, msg=None)	verification expr yes true, If false, be fail
4	assertFalse(expr,msg=None)	verification expr yes false, If true, be fail
5	assertIs(arg1, arg2, msg=None)	verification arg1、arg2 Is the same object , Not so fail
6	assertIsNot(arg1, arg2, msg=None)	verification arg1、arg2 Not the same object , it is then fail
7	assertIsNone(expr, msg=None)	verification expr yes None, Not so fail
8	assertIsNotNone(expr, msg=None)	verification expr No None, it is then fail
9	assertIn(arg1, arg2, msg=None)	verification arg1 yes arg2 The string of , Not so fail
10	assertNotIn(arg1, arg2, msg=None)	verification arg1 No arg2 The string of , it is then fail
11	assertIsInstance(obj, cls, msg=None)	verification obj yes cls Example , Not so fail
12	assertNotIsInstance(obj, cls, msg=None)	verification obj No cls Example , it is then fail

import time
from selenium import webdriver
import unittest


class Baidu1(unittest.TestCase):
    # Test Inherited from unittest.TestCase
    #  Test firmware  setup and tearDown
    #  there self It is equivalent to an example 
    def setUp(self):
        self.driver = webdriver.Chrome()
        self.url = "http://www.baidu.com/"
        self.driver.maximize_window()

    def tearDown(self):
        self.driver.quit()

    #  The test method name must be test_ Otherwise, it will not be carried out 
    def test_baidu1(self):
        driver = self.driver
        driver.get(self.url)
        driver.find_element_by_id("kw").send_keys("kobe")
        driver.find_element_by_id("su").click()
        
        #  Add assertions 
        self.assertEqual("kobe", driver.find_element_by_link_text(" Kobe · Bryant  -  Baidu Encyclopedia ").text,msg="kobe！= Kobe · Bryant  -  Baidu Encyclopedia ")
        
        time.sleep(3)

    if __name__ == "__main__":
        unittest.main(2)


'''  Can increase verbosity Parameters , for example unittest.main(verbosity=2)  In the main function , Call directly main() , stay main Add verbosity=2 , In this way, the test results will be displayed in more detail .  there verbosity  It's an option ,  Represents the information complexity of the test results , There are three values : 0 (  silent mode ):  You can only get the total number of test cases and total results, such as a total of 100 A failure ,20  success 80 1 (  The default mode ):  It's very similar to the silent mode, except that there is a... In front of each successful use case “ . ”  Each failed use case is preceded by a “F” 2 (  Detailed mode ):  The test results show all the relevant information for each test case  '''

Can pass IDE To add assertions ：

HTML Report generation

After the script is executed , Still need to see HTML The report , Let's go through HTMLTestRunner.py To generate test reports .

HTMLTestRunner Support python2.7.python3 See the code in the following website , Copy and paste between https://blog.csdn.net/liubo37/article/details/105069609/

HTMLTestRunner.py file , Download address ：
http://tungwaiyip.info/software/HTMLTestRunner.html
After downloading, put it in testcase To go or put into a directory …\Python27\Lib Under the table of contents （windows）.

modify runall.py

# -*- coding: utf-8 -*-
import unittest,csv
import os,sys
import time
import HTMLTestRunner
# Manually add cases to the suite ,
def createsuite():
 
discover=unittest.defaultTestLoader.discover('../test',pattern='test*.py',top_level_dir=None)
 print discover
 return discover
 if __name__=="__main__":
 curpath=sys.path[0]
 # Solve the problem of duplicate naming 
 now=time.strftime("%Y-%m-%d-%H %M %S",time.localtime(time.time()))
 #  Under the current path resulreport Create a folder when it doesn't exist 
 if not os.path.exists(curpath+'/resultreport'):
 os.makedirs(curpath+'/resultreport')
 # The file name is the path plus the name of the file 
 # Get ready HTML Report output file 
 filename=curpath+'/resultreport/'+now+'resultreport.html'
 # open HTML file ,wb  In writing 
 with open(filename,'wb') as fp:
 # Out html The report , The parameters in parentheses are HTML The parameters in the report 
 runner=HTMLTestRunner.HTMLTestRunner(stream=fp,title=u' Test report ',description=u' Use case execution 
 situation ',verbosity=2)
 suite=createsuite()
 runner.run(suite)

Exception capture and error screenshot

Use cases cannot succeed every time they run , There must be some unsuccessful times when it runs . If you can catch errors , And save the error screenshot , This will be a great feature , It will also bring convenience to our wrong positioning .

For example, write a screenshot function , The key statement is driver.get_screenshot_as_file：

def savescreenshot(self,driver,file_name):
 if not os.path.exists('./image'):
 os.makedirs('./image')
 now=time.strftime("%Y%m%d-%H%M%S",time.localtime(time.time()))
 # Screenshot save 
 driver.get_screenshot_as_file('./image/'+now+'-'+file_name)
 time.sleep(1)

A quoted example ：

# -*- coding: utf-8 -*-
from selenium import webdriver
from selenium.webdriver.common.by import By
from selenium.webdriver.common.keys import Keys
from selenium.webdriver.support.ui import Select
from selenium.common.exceptions import NoSuchElementException
from selenium.common.exceptions import NoAlertPresentException
import unittest, time, re
import os
class Baidu1(unittest.TestCase):
#test fixture, Initialization environment 
 def setUp(self):
 self.driver = webdriver.Firefox()
 self.driver.implicitly_wait(30)
 self.base_url = "http://www.baidu.com/"
 self.verificationErrors = []
 self.accept_next_alert = True
 # The test case , Must be test start  
 
 def test_hao(self):
 driver = self.driver
 driver.get(self.base_url + "/")
 driver.find_element_by_link_text("hao123").click()
 time.sleep(2)
 try:
 self.assertEqual(u'hao_ Internet starts here ', driver.title)
 except:
 self.savescreenshot(driver,'hao.png')
 
 # Judge element Whether there is , Deleting  
 def is_element_present(self, how, what):
 try: self.driver.find_element(by=how, value=what)
 except NoSuchElementException as e: return False
 return True
 # Judge alert Whether there is , Deleting  
 def is_alert_present(self):
 try: self.driver.switch_to_alert()
 except NoAlertPresentException as e: return False
 return True
 # close alert, Deleting  
 def close_alert_and_get_its_text(self):
 try:
 alert = self.driver.switch_to_alert()
 alert_text = alert.text
 if self.accept_next_alert:
 alert.accept()
 else:
 alert.dismiss()
 return alert_text
 finally: self.accept_next_alert = True
 #test fixture, Clear the environment  
 def tearDown(self):
 self.driver.quit()
 self.assertEqual([], self.verificationErrors)
 def savescreenshot(self,driver,file_name):
 if not os.path.exists('./image'):
 os.makedirs('./image')
 now=time.strftime("%Y%m%d-%H%M%S",time.localtime(time.time()))
 # Screenshot save 
 driver.get_screenshot_as_file('./image/'+now+'-'+file_name)
 time.sleep(1)
if __name__ == "__main__":
# Execute use cases 
 unittest.main()

 '''  Can increase verbosity Parameters , for example unittest.main(verbosity=2)  In the main function , Call directly main() , stay main Add verbosity=2 , In this way, the test results will be displayed in more detail .  there verbosity  It's an option ,  Represents the information complexity of the test results , There are three values : 0 (  silent mode ):  You can only get the total number of test cases and total results, such as a total of 100 A failure ,20  success 80 1 (  The default mode ):  It's very similar to the silent mode, except that there is a... In front of each successful use case “ . ”  Each failed use case is preceded by a “F” 2 (  Detailed mode ):  The test results show all the relevant information for each test case  '''