python - 如何在 Python 中处理 AssertionError 并找出它发生在哪一行或哪条语句上？

Question

我想处理 AssertionError 以向用户隐藏堆栈跟踪的不必要部分，并打印一条消息，说明错误发生的原因以及用户应该如何处理。

有什么方法可以找出 except block 中 assert 在哪一行或哪条语句上失败？

try:
    assert True
    assert 7 == 7
    assert 1 == 2
    # many more statements like this
except AssertionError:
    print 'Houston, we have a problem.'
    print
    print 'An error occurred on line ???? in statement ???'
    exit(1)

我不想把这个添加到每个断言语句中:

assert 7 == 7, "7 == 7"

因为它重复信息。

Answer 1

使用 traceback模块:

import sys
import traceback

try:
    assert True
    assert 7 == 7
    assert 1 == 2
    # many more statements like this
except AssertionError:
    _, _, tb = sys.exc_info()
    traceback.print_tb(tb) # Fixed format
    tb_info = traceback.extract_tb(tb)
    filename, line, func, text = tb_info[-1]

    print('An error occurred on line {} in statement {}'.format(line, text))
    exit(1)