我从python.org unittest文档中逐字复制了这个:
import random
import unittest
class TestSequenceFunctions(unittest.TestCase):
def setUp(self):
self.seq = range(10)
def test_shuffle(self):
# make sure the shuffled sequence does not lose any elements
random.shuffle(self.seq)
self.seq.sort()
self.assertEqual(self.seq, range(10))
# should raise an exception for an immutable sequence
self.assertRaises(TypeError, random.shuffle, (1,2,3))
def test_choice(self):
element = random.choice(self.seq)
self.assertTrue(element in self.seq)
def test_sample(self):
with self.assertRaises(ValueError):
random.sample(self.seq, 20)
for element in random.sample(self.seq, 5):
self.assertTrue(element in self.seq)
if __name__ == '__main__':
unittest.main()
但我在linux2上从python 2.7.2 [GCC 4.1.2 20080704(Red Hat 4.1.2-51)]中得到此错误消息:
.E.
======================================================================
ERROR: test_sample (__main__.TestSequenceFunctions)
----------------------------------------------------------------------
Traceback (most recent call last):
File "tmp.py", line 23, in test_sample
with self.assertRaises(ValueError):
TypeError: failUnlessRaises() takes at least 3 arguments (2 given)
----------------------------------------------------------------------
Ran 3 tests in 0.001s
FAILED (errors=1)
如何让assertRaises()
正常工作?
答案 0 :(得分:7)
在python 2.7中添加了使用unittest.TestCase.AssertRaises()作为上下文管理器的能力。 http://docs.python.org/2/library/unittest.html#unittest.TestCase.assertRaises
答案 1 :(得分:6)
检查你是否真的使用2.7 python。
使用pythonbrew
进行测试:
$ pythonbrew use 2.7.2
$ python test.py
...
----------------------------------------------------------------------
Ran 3 tests in 0.000s
OK
$ pythonbrew use 2.6.5
$ python test.py
.E.
======================================================================
ERROR: test_sample (__main__.TestSequenceFunctions)
----------------------------------------------------------------------
Traceback (most recent call last):
File "test.py", line 23, in test_sample
with self.assertRaises(ValueError):
TypeError: failUnlessRaises() takes at least 3 arguments (2 given)
----------------------------------------------------------------------
Ran 3 tests in 0.000s
FAILED (errors=1)
答案 2 :(得分:0)
如果您使用的是2.7仍然看到此问题,则可能是因为您没有使用python的unittest
模块。其他一些模块,例如twisted
提供了assertRaises
,尽管它们尝试保持与python的unittest
的兼容性,但是该模块的特定版本可能已过时。