在没有-O选项的情况下,脚本会抛出AssertionError。而在带有-O选项的情况下,脚本不会抛出任何异常,并输出“Assertions are disabled, no AssertionError raised”。 总结来说,使用命令行参数-O是禁用Python中assert语句的最推荐方法。这种方法简单、有效,并且不会影响代码的其他部分。
Add error messages to assert statementsWhen an AssertionError is raised, it's sometimes unclear what went wrong.>>> x = 7 >>> y = 10 >>> assert x == y Traceback (most recent call last): File "<stdin>", line 1, in <module> AssertionError When Python runs an assert statement,...
| self.assertEqual(the_exception.error_code, 3) | | assertRaisesRegexp(self, expected_exception, expected_regexp, callable_obj=None, *args, **kwargs) | Asserts that the message in a raised exception matches a regexp. | | Args: | expected_exception: Exception class expected to be raised...
runoob()exceptAssertionError as error:print(error)else:try: with open('file.log') as file: read_data=file.read()exceptFileNotFoundError as fnf_error:print(fnf_error)finally:print('这句话,无论异常是否发生都会执行。') 抛出异常 Python 使用 raise 语句抛出一个指定的异常。 raise语法格式如下: ...
exception AssertionError Raised when an assert statement fails. (2) https://docs.python.org/3/reference/simple_stmts.html#the-assert-statement "assert ..." is equivalent to "if __debug__: ..." From this, one can infer the guarantee "the -O flag will suppress AssertionError exceptions ...
当使用 python testAssert.py 运行时,内置属性 __debug__ 会输出 True,assert 1 > 2 语句会抛出 AssertionError 异常。 当使用 python -O testAssert.py 运行时,内置属性 __debug__ 会输出 False,assert 1 > 2 语句由于没有执行不会报任何异常。
Either way, the raised exception breaks your program’s execution. Most of the time, you won’t raise AssertionError exceptions explicitly in your code. The assert statement takes care of raising this exception when the assertion condition fails. Additionally, you shouldn’t attempt to handle ...
In the case above, the code informs the user about the error more clearly. If an exception is raised due to the code in the try block, the execution continues with the statements in the except block. So, it is up to the programmer how to handle the exception. The plain try-except bl...
❮ Python Keywords ExampleGet your own Python Server Test if a condition returns True: x ="hello" #if condition returns True, then nothing happens: assertx =="hello" #if condition returns False, AssertionError is raised: assertx =="goodbye" ...
import pytestdef test_match(): with pytest.raises((ValueError, RuntimeError), match=r'.* 123 .*'): raise ValueError("Exception 123 raised") # 异常的字符串表示 是否符合 给定的正则表达式 解释:pytest实际调用的是 re.search() 方法来做上述检查;并且 ,pytest.raises() 也支持检查多个期望异常(以...