我只是写了一个钩子，每个测试都会得到

诱惑:

@pytest。hookimpl (tryfirst = True, hookwrapper = True) def pytest_runtest_makereport(item: item, call: CallInfo):

    outcome = yield  # The result after the test is completed
    result = outcome.get_result()

    if result.when == "call":
       if result.failed == True:

       else:

我有一个函数，更新一个文档与测试结果，并通过使用:result.longrepr.reprcrash.message添加跟踪

我不知道这是否是最好的方法，但它确实回答了如何仅使用pytest打印回溯的问题

@显然我有一些其他的代码

如果你想测试特定的错误类型，可以使用try, catch和raise的组合:

#-- test for TypeError
try:
  myList.append_number("a")
  assert False
except TypeError: pass
except: assert False

只是添加了另一个“愚蠢”的建议，因为我在现有的答案中没有看到它。本质上，你可以初始化一个错误变量为None，在try/except块中做这件事，然后在那之后检查错误变量的类/值

e = None

try:
    blah()
except Exception as exc:
    e = exc

assert e.__class__ == ValueError # or whatever you expect
assert str(e) == "expected message"

更好的做法是使用继承unittest的类。TestCase和运行self.assertRaises。

例如:

import unittest


def whatever():
    return 9/0


class TestWhatEver(unittest.TestCase):

    def test_whatever():
        with self.assertRaises(ZeroDivisionError):
            whatever()

然后运行以下命令执行:

pytest -vs test_path

你可以试试

def test_exception():
    with pytest.raises(Exception) as excinfo:   
        function_that_raises_exception()   
    assert str(excinfo.value) == 'some info' 

pytest.raise (Exception)是你所需要的。

Code

import pytest

def test_passes():
    with pytest.raises(Exception) as e_info:
        x = 1 / 0

def test_passes_without_info():
    with pytest.raises(Exception):
        x = 1 / 0

def test_fails():
    with pytest.raises(Exception) as e_info:
        x = 1 / 1

def test_fails_without_info():
    with pytest.raises(Exception):
        x = 1 / 1

# Don't do this. Assertions are caught as exceptions.
def test_passes_but_should_not():
    try:
        x = 1 / 1
        assert False
    except Exception:
        assert True

# Even if the appropriate exception is caught, it is bad style,
# because the test result is less informative
# than it would be with pytest.raises(e)
# (it just says pass or fail.)

def test_passes_but_bad_style():
    try:
        x = 1 / 0
        assert False
    except ZeroDivisionError:
        assert True

def test_fails_but_bad_style():
    try:
        x = 1 / 1
        assert False
    except ZeroDivisionError:
        assert True

输出

============================================================================================= test session starts ==============================================================================================
platform linux2 -- Python 2.7.6 -- py-1.4.26 -- pytest-2.6.4
collected 7 items 

test.py ..FF..F

=================================================================================================== FAILURES ===================================================================================================
__________________________________________________________________________________________________ test_fails __________________________________________________________________________________________________

    def test_fails():
        with pytest.raises(Exception) as e_info:
>           x = 1 / 1
E           Failed: DID NOT RAISE

test.py:13: Failed
___________________________________________________________________________________________ test_fails_without_info ____________________________________________________________________________________________

    def test_fails_without_info():
        with pytest.raises(Exception):
>           x = 1 / 1
E           Failed: DID NOT RAISE

test.py:17: Failed
___________________________________________________________________________________________ test_fails_but_bad_style ___________________________________________________________________________________________

    def test_fails_but_bad_style():
        try:
            x = 1 / 1
>           assert False
E           assert False

test.py:43: AssertionError
====================================================================================== 3 failed, 4 passed in 0.02 seconds ======================================================================================

请注意，e_info保存了异常对象，因此您可以从中提取详细信息。例如，如果您想检查异常调用堆栈或内部的另一个嵌套异常。