Question

我有一个单元测试，用于检查构造函数中的异常：

import unittest
from jaboci import Jacobi

class TestJacobi(unittest.TestCase):

    def test_even(self):
        a = 11
        n = 12
        Jacobi(a, n)
        self.assertRaises(ValueError, Jacobi, a, n)

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

受测试的课程：

class Jacobi:

    def __init__(self, a, n):
        self.a = a
        self.n = n
        if n % 2 == 0:
            raise ValueError("N must be odd.")

当我使用-m unittest discover运行unittest时，测试失败：

E
======================================================================
ERROR: test_even (test_jacobi.TestJacobi)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/home/prasopes/prg/python/PycharmProjects/jacobi_symbol/test_jacobi.py", line 9, in test_even
    Jacobi(a, n)
  File "/home/prasopes/prg/python/PycharmProjects/jacobi_symbol/jaboci.py", line 7, in __init__
    raise ValueError("N must be odd.")
ValueError: N must be odd.

----------------------------------------------------------------------
Ran 1 test in 0.000s

FAILED (errors=1)

Answer 1

您在Jacobi(a, n)之前致电self.assertRaises(ValueError, Jacobi, a, n)。您获得的例外是第一次调用，因此测试立即失败。它永远不会到达assertRaises。

Answer 2

[由于我没有足够的代表评论@mata答案...]

为了清楚起见，你需要

删除Jacobi(a, n) [暗示@mata]
或者，叫'Jacobi（n，a）'[由@abarnert对@mata发表评论]

assertRaises没有捕获异常

2 个答案: