相关疑难解决方法(0)

Python raise和raise fromPython 之间的区别是什么？

try:
    raise ValueError
except Exception as e:
    raise IndexError

产量

Traceback (most recent call last):
  File "tmp.py", line 2, in <module>
    raise ValueError
ValueError

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "tmp.py", line 4, in <module>
    raise IndexError
IndexError

和

try:
    raise ValueError
except Exception as e:
    raise IndexError from e

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Traceback (most recent call last):
  File "tmp.py", line 2, in <module>
    raise ValueError …

我正在尝试编写一个pytest插件来自定义特定异常的外观 - 更具体地说,模拟异常(预期被调用的方法没有被调用等),因为在这些异常的追溯中存在大量无用的噪声.

这是我到目前为止所做的,它有效,但非常黑客:

import pytest
import flexmock

@pytest.hookimpl()
def pytest_exception_interact(node, call, report):
    exc_type = call.excinfo.type

    if exc_type == flexmock.MethodCallError:
        entry = report.longrepr.reprtraceback.reprentries[-1]
        entry.style = 'short'
        entry.lines = [entry.lines[-1]]
        report.longrepr.reprtraceback.reprentries = [entry]

我认为我正在hookimpl使用简单的if语句检查异常类型.

我尝试report.longrepr用一个简单的字符串替换,这也有效,但后来我失去了格式化(终端中的颜色).

作为我想缩短的输出类型的一个例子,这是一个模拟断言失败:

=================================== FAILURES ====================================
_______________________ test_session_calls_remote_client ________________________

    def test_session_calls_remote_client():
        remote_client = mock.Mock()
        session = _make_session(remote_client)
        session.connect()
        remote_client.connect.assert_called_once_with()
        session.run_action('asdf')
>       remote_client.run_action.assert_called_once_with('asdff')

tests/unit/executor/remote_test.py:22: 
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