带assert语句的Python unittests（带异常）

Posted 2021-02-26

method 'E' (in fact a decorator) catch the execption and return it, so it's possible to use the good old assert statement.

import sys
 
def E(m):
    def _c(*a,**k):
        try:
            return m(*a,**k)
        except:
            return sys.exc_info()[0]
    return _c
 
def methodToTest(x):
    return 2/x
 
if __name__ == "__main__":
    assert methodToTest(2)==1
    assert methodToTest(1)==2
    assert E(methodToTest)(0)==ZeroDivisionError
 
    # alternative way :
 
    methodToTest = E(methodToTest) # force decoration
    assert methodToTest(1)==2
    assert methodToTest(2)==1
    assert methodToTest(0)==ZeroDivisionError