pytest扫盲16--某个用例失败后，关联的用例标记为xfail

设计思路：设计用例时，如果用例执行失败，则标记 xfail，所有引用该用例的其他用例，均调用该 xfail 标记

示例：

# File  : test_demo_16.py
# IDE   : PyCharm

import pytest

@pytest.fixture(params=[{'user': 'admin', 'pwd': '1234'}])
def login(request):
    '''前置条件登录'''
    print("\n正在操作登录，账号：%s, 密码：%s" % (request.param['user'], request.param['pwd']))
    if request.param['pwd'] == '123456':
        print('登录成功')
        return True
    else:
        print('登录失败')
        pytest.xfail(reason='登录失败，标记为xfail')
        return False

class TestLogin:
    def test_1(self, login):
        assert 5 > 6

    def test_2(self, login):
        assert 'h' in 'hello'

    def test_3(self):
        assert 3 is 3

当前置条件执行失败时，执行结果：

E:\personal\python38\python.exe E:/personal/GitWorkSpace/pytest_basic/main.py
test_demo_16.py::TestLogin::test_1[login0]
test_demo_16.py::TestLogin::test_2[login0]
test_demo_16.py::TestLogin::test_3

正在操作登录，账号：admin, 密码：1234
登录失败
x
正在操作登录，账号：admin, 密码：1234
登录失败
x.
1 passed, 2 xfailed in 0.11s

Process finished with exit code 0

当前置条件执行成功时，执行结果：

E:\personal\python38\python.exe E:/personal/GitWorkSpace/pytest_basic/main.py
test_demo_16.py::TestLogin::test_1[login0]
test_demo_16.py::TestLogin::test_2[login0]
test_demo_16.py::TestLogin::test_3

正在操作登录，账号：admin, 密码：123456
登录成功
F
正在操作登录，账号：admin, 密码：123456
登录成功
..
================================== FAILURES ===================================
__________________________ TestLogin.test_1[login0] ___________________________

self = <pytest_basic.test_demo_16.TestLogin object at 0x000000B010FF80A0>
login = True

    def test_1(self, login):
>       assert 5 > 6
E       assert 5 > 6

test_demo_16.py:24: AssertionError
=========================== short test summary info ===========================
FAILED test_demo_16.py::TestLogin::test_1[login0] - assert 5 > 6
1 failed, 2 passed in 0.13s

Process finished with exit code 0