2017-04-20 70 views
0

我測試使用assertRaises一個例外,即使引發異常,它不是由assertRaisesassertRaises:雖然做了方法

這裏檢測的單元測試KeyError異常異常沒有提出是方法測試:

def process_data(data): 
    """ 
    process output data 
    :return: dict object 
    """ 
    component = dict() 
    try: 
     properties = dict() 
     properties['state'] = data['state'] 
     properties['status'] = data['status'] 
     component['properties'] = properties 
    except KeyError as e: 
     print "Missing key '{0}' in the response data".format(str(e)) 

    return component 

sample_data = {} 
process_data(sample_data) 

而且測試代碼:

import unittest 
import test_exception 


class TestExceptions(unittest.TestCase): 
    """ 
    test class 
    """ 
    def test_process_data(self): 
     """ 
     test 
     :return: 
     """ 
     sample = {} 
     self.assertRaises(KeyError, test_exception.process_data, sample) 

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

但它不是按預期工作,得到如下錯誤:

unittest -p test_test_exception.py 
Missing key ''state'' in the response data 


Missing key ''state'' in the response data 


Failure 
Traceback (most recent call last): 
    File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/unittest/case.py", line 331, in run 
    testMethod() 
    File "/unittest/test_test_exception.py", line 16, in test_process_data 
    self.assertRaises(KeyError, test_exception.process_data, sample) 
    File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/unittest/case.py", line 475, in assertRaises 
    callableObj(*args, **kwargs) 
    File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/unittest/case.py", line 116, in __exit__ 
    "{0} not raised".format(exc_name)) 
AssertionError: KeyError not raised 



Ran 1 test in 0.001s 

FAILED (failures=1) 

Process finished with exit code 1 

什麼是錯的單元測試用例?

回答

0

感謝您張貼與適當的環境和代碼一個清晰的問題。這裏的問題:

except KeyError as e: 
    print "Missing key '{0}' in the response data".format(str(e)) 

這應該是:

except KeyError as e: 
    print "Missing key '{0}' in the response data".format(str(e)) 
    raise 

單元測試是檢查異常升高(其中的代碼是短路完全)。查找異常類型並打印消息與使用raise關鍵字引發錯誤不同。

+0

並不意味着,如果你是在攔網除外,這意味着將引發異常? –

+0

沒有,'except'塊是例外時「中招」,意思是注意到了,但不上調。您可以選擇提高或處理它。 assertRaises()特別檢查引發行爲。 – JacobIRR

+0

哦確定,究竟什麼是單​​元測試這種情況下,我們要優雅地處理異常並沒有引起任何的最佳方式,可只要登錄並繼續前進? –