python中的單元測試

python中的單元測試可以使用doctest,unittest完成

1.doctest的使用

(1)寫入程式如下(cubetest.py)：

#!/usr/bin/pythondef cube(x):"""cube a number and return the result>>> cube(2)8>>> cube(3)27>>> cube(4)64"""return x**3;if __name__=='__main__':import doctest;doctest.testmod(verbose=True);

測試案例寫在字串””” cube a number… “””中。

調用doctest中的testmod的方法即可測試。

輸出如下：

Trying:

cube(2)

Expecting:

8

ok

Trying:

cube(3)

Expecting:

27

ok

Trying:

cube(4)

Expecting:

64

ok

1 itemshad no tests:

__main__

1 itemspassed all tests:

3 tests in __main__.cube

3 testsin 2 items.

3 passedand 0 failed.

Testpassed.

TestResults(failed=0, attempted=3)

(2)也可以把測試案例寫在記事本檔案中。建立記事本example.txt,寫入以下內容：

>>> from cubetest import cube

>>> cube(1)

1

>>> cube(2)

8

>>> cube(4)

64

然後寫測試代碼 test.py：

import doctestdoctest.testfile("example.txt")

使用python test.py –v 執行測試代碼，可以得到以下結果

Trying:

from cubetest import cube

Expectingnothing

ok

Trying:

cube(1)

Expecting:

1

ok

Trying:

cube(2)

Expecting:

8

ok

Trying:

cube(4)

Expecting:

64

ok

1 items passedall tests:

4 tests in example.txt

4 tests in 1items.

4 passed and 0failed.

Test passed.

2.unittest的使用

(1)寫待測試的程式如下：

def iseven(x):if(x%2==0):return 1;else:return 0;def isodd(x):if(x%2==1):return 1;else:return 0;

測試程式中的類eventest類繼承自TestCase,它包含setUp() ,test_1(),test_2()和tearDown()四個方法。在測試回合前，會自動運行setUp()方法，在測試完成之前，會自動調用tearDown()方法。test_1()和test_2()是自訂的測試方法。寫測試程式如下：

import unittest,evenoddclass eventest(unittest.TestCase):def setUp(self):self.ex1=range(0,2,20);self.ex2=range(1,2,20);def test_1(self):for x in self.ex1:x=evenodd.iseven(x);self.assertEqual(x,1);for x in self.ex2:x=evenodd.iseven(x);self.assertEqual(x,0);def test_2(self):for x in self.ex1:x=evenodd.isodd(x);self.assertEqual(x,0);for x in self.ex2:x=evenodd.isodd(x);self.assertEqual(x,1);def tearDown(self):self.ex1=None;self.ex2=None;if __name__=='__main__':unittest.main();

上面用到了self.AssertEqual(),類似的判斷方法還有：

assertNotEqual(a,b) a!=b

asserTrue(x) bool(x)為真

assertFalse(x) bool(x)為假

assertIs(a,b) a is b

assertIsNot(a,b) a is not b

assertIsNone(x) x is None

assertIsNotNone(x) x is not None

assertIn (a,b) a in b

assertNotIn(a,b) a not in b

assertIsInstance(a,b) isinstance(a,b)

assertNotIsInstance(a,b) not instance(a,b)

(2) 也可以使用TestSuite對測試案例進行封裝，下面的程式定義了類evensuite，它繼承自類TestSuite，方法addTest()用於添加測試方法。

測試程式如下：

import unittest,evenoddclass eventest(unittest.TestCase):def setUp(self):self.ex1=range(0,2,20);self.ex2=range(1,2,20);def test_1(self):for x in self.ex1:x=evenodd.iseven(x);self.assertEqual(x,1);for x in self.ex2:x=evenodd.iseven(x);self.assertEqual(x,0);def test_2(self):for x in self.ex1:x=evenodd.isodd(x);self.assertEqual(x,0);for x in self.ex2:x=evenodd.isodd(x);self.assertEqual(x,1);def tearDown(self):self.ex1=None;self.ex2=None;class evensuite(unittest.TestSuite):def suite(self):suite=unittest.TestSuite();suite.addTest(eventest('test_1'));suite.addTest(eventest('test_2'));return suite;if __name__=='__main__':unittest.main();

運行程式 ，結果輸出：

_ _

ran 2 tests in 0.001s

OK