Pytest参数选项自由执行测试用例详解（二）

王大力测试进阶之路

发布于 2021-07-28 16:10:08

8370

发布于 2021-07-28 16:10:08

运行pytest可以指定目录和文件，如果不指定，pytest会搜索当前目录及其子目录中以test_开头或以_test结尾得测试函数。我们把pytest搜索测试文件和测试用例的过程称为测试搜索（test discovery）。只要遵循pytest的命名规则，pytest就能自动搜索所有待执行的测试用例。所有的包必须要有init.py文件(在使用各种编辑器时会自动生成)

1、测试文件命名规则，test_xxx.py或xxx_test.py

2、方法、测试函数命名规则，test_xxx

3、测试类命名规则，Testxxx，并且不能带有 init 方法

Pytest参数选项在脚本中和命令行用法详解（一）

-k选项 -K EXPRESSION

使用表达式指定某个关键字的测试用例，如果某测试名是唯一的或多个测试名的前缀或后缀相同，可快速匹配，匹配范围是全局相同目录或下层目录所有（包名、文件名、类名、函数名为变量），文件名、类名、函数名，必须是test_开头或_test结尾的。

pytest.main(['-k','关键字'])
关键字包含于或等于文件名、类名、函数名，多个关键字之间用and、or、not连接

测试代码如下：

chengzi\test_04.py

import pytest


class TestClass(object):
    def test_one(self):
        assert 2 == 1


    def test_two(self):
        assert 2 == 2

    def test_two2(self):
        assert 2 == 2

执行匹配包名，运行了3条用例

pytest.main(['-v','-k','chengzi'])

if __name__ == '__main__':
    pytest.main(['-v','-k','chengzi'])
    
 "C:\Program Files\Python35\python.exe" C:/Users/wangli/PycharmProjects/untitled/chengzi/test_04.py
============================= test session starts =============================
platform win32 -- Python 3.5.2, pytest-6.1.1, py-1.9.0, pluggy-0.13.1 -- C:\Program Files\Python35\python.exe
cachedir: .pytest_cache
metadata: {'Packages': {'pluggy': '0.13.1', 'py': '1.9.0', 'pytest': '6.1.1'}, 'Platform': 'Windows-10-10.0.18362-SP0', 'JAVA_HOME': 'C:\\Program Files\\Java\\jdk1.8.0_101', 'Python': '3.5.2', 'Plugins': {'allure-pytest': '2.8.18', 'metadata': '1.8.0', 'rerunfailures': '9.1.1', 'html': '1.22.0'}}
rootdir: C:\Users\wangli\PycharmProjects\untitled\chengzi
plugins: allure-pytest-2.8.18, html-1.22.0, metadata-1.8.0, rerunfailures-9.1.1
collecting ... collected 3 items

test_04.py::TestClass::test_one FAILED                                   [ 33%]
test_04.py::TestClass::test_two PASSED                                   [ 66%]
test_04.py::TestClass::test_two2 PASSED                                  [100%]

================================== FAILURES ===================================
_____________________________ TestClass.test_one ______________________________

self = <chengzi.test_04.TestClass object at 0x000001F27E537B70>

    def test_one(self):
>       assert 2 == 1
E       assert 2 == 1
E         +2
E         -1

test_04.py:5: AssertionError
=========================== short test summary info ===========================
FAILED test_04.py::TestClass::test_one - assert 2 == 1
========================= 1 failed, 2 passed in 0.63s =========================

Process finished with exit code 0

执行匹配文件名，运行了3条用例

pytest.main(['-v','-k','test_04.py'])

if __name__ == '__main__':
    pytest.main(['-v','-k','test_04.py'])
    
"C:\Program Files\Python35\python.exe" C:/Users/wangli/PycharmProjects/untitled/chengzi/test_04.py
============================= test session starts =============================
platform win32 -- Python 3.5.2, pytest-6.1.1, py-1.9.0, pluggy-0.13.1 -- C:\Program Files\Python35\python.exe
cachedir: .pytest_cache
metadata: {'Platform': 'Windows-10-10.0.18362-SP0', 'Python': '3.5.2', 'Packages': {'py': '1.9.0', 'pluggy': '0.13.1', 'pytest': '6.1.1'}, 'JAVA_HOME': 'C:\\Program Files\\Java\\jdk1.8.0_101', 'Plugins': {'rerunfailures': '9.1.1', 'html': '1.22.0', 'allure-pytest': '2.8.18', 'metadata': '1.8.0'}}
rootdir: C:\Users\wangli\PycharmProjects\untitled\chengzi
plugins: allure-pytest-2.8.18, html-1.22.0, metadata-1.8.0, rerunfailures-9.1.1
collecting ... collected 3 items

test_04.py::TestClass::test_one FAILED                                   [ 33%]
test_04.py::TestClass::test_two PASSED                                   [ 66%]
test_04.py::TestClass::test_two2 PASSED                                  [100%]

================================== FAILURES ===================================
_____________________________ TestClass.test_one ______________________________

self = <chengzi.test_04.TestClass object at 0x000002031D345588>

    def test_one(self):
>       assert 2 == 1
E       assert 2 == 1
E         +2
E         -1

test_04.py:6: AssertionError
=========================== short test summary info ===========================
FAILED test_04.py::TestClass::test_one - assert 2 == 1
========================= 1 failed, 2 passed in 0.48s =========================

Process finished with exit code 0

执行匹配类名，运行了3条用例

pytest.main(['-v','-k','Class'])


if __name__ == '__main__':
    pytest.main(['-v','-k','Class'])

"C:\Program Files\Python35\python.exe" C:/Users/wangli/PycharmProjects/untitled/chengzi/test_04.py
============================= test session starts =============================
platform win32 -- Python 3.5.2, pytest-6.1.1, py-1.9.0, pluggy-0.13.1 -- C:\Program Files\Python35\python.exe
cachedir: .pytest_cache
metadata: {'Plugins': {'html': '1.22.0', 'rerunfailures': '9.1.1', 'metadata': '1.8.0', 'allure-pytest': '2.8.18'}, 'Packages': {'pluggy': '0.13.1', 'py': '1.9.0', 'pytest': '6.1.1'}, 'JAVA_HOME': 'C:\\Program Files\\Java\\jdk1.8.0_101', 'Python': '3.5.2', 'Platform': 'Windows-10-10.0.18362-SP0'}
rootdir: C:\Users\wangli\PycharmProjects\untitled\chengzi
plugins: allure-pytest-2.8.18, html-1.22.0, metadata-1.8.0, rerunfailures-9.1.1
collecting ... collected 3 items

test_04.py::TestClass::test_one FAILED                                   [ 33%]
test_04.py::TestClass::test_two PASSED                                   [ 66%]
test_04.py::TestClass::test_two2 PASSED                                  [100%]

================================== FAILURES ===================================
_____________________________ TestClass.test_one ______________________________

self = <chengzi.test_04.TestClass object at 0x0000023ED5C68B00>

    def test_one(self):
>       assert 2 == 1
E       assert 2 == 1
E         +2
E         -1

test_04.py:6: AssertionError
=========================== short test summary info ===========================
FAILED test_04.py::TestClass::test_one - assert 2 == 1
========================= 1 failed, 2 passed in 0.21s =========================

Process finished with exit code 0

执行匹配函数名，函数名中含test且含two的，运行了2条用例

pytest.main(['-v','-k','test and two'])

if __name__ == '__main__':
    pytest.main(['-v','-k','test and two'])

"C:\Program Files\Python35\python.exe" C:/Users/wangli/PycharmProjects/untitled/chengzi/test_04.py
============================= test session starts =============================
platform win32 -- Python 3.5.2, pytest-6.1.1, py-1.9.0, pluggy-0.13.1 -- C:\Program Files\Python35\python.exe
cachedir: .pytest_cache
metadata: {'Platform': 'Windows-10-10.0.18362-SP0', 'JAVA_HOME': 'C:\\Program Files\\Java\\jdk1.8.0_101', 'Plugins': {'rerunfailures': '9.1.1', 'html': '1.22.0', 'allure-pytest': '2.8.18', 'metadata': '1.8.0'}, 'Packages': {'pluggy': '0.13.1', 'py': '1.9.0', 'pytest': '6.1.1'}, 'Python': '3.5.2'}
rootdir: C:\Users\wangli\PycharmProjects\untitled\chengzi
plugins: allure-pytest-2.8.18, html-1.22.0, metadata-1.8.0, rerunfailures-9.1.1
collecting ... collected 3 items / 1 deselected / 2 selected

test_04.py::TestClass::test_two PASSED                                   [ 50%]
test_04.py::TestClass::test_two2 PASSED                                  [100%]

======================= 2 passed, 1 deselected in 0.11s =======================

Process finished with exit code 0

-m选项 -m MARKEXPR

标记（marker）用于标记测试并分组，以便快速选中并运行，匹配运行所有标记了装饰器@pytest.mark.marker的类或方法的测试用例，标记名可自行定义，如果标记名为run_all,可使用@pytest.mark.run_all装饰类或函数来做标记，匹配范围是全局相同目录或下层目录所有（类装饰器的标记名、函数装饰器的标记名），文件名、类名、函数名，必须是test_开头或_test结尾的。

pytest.main(['-v','-m','关键字'])
关键字等于类装饰器或函装饰器@pytest.mark.标记名，里的标记名，多个关键字之间用and、or、not连接

测试代码目录：

测试代码：

chengzi\test_01.py
import pytest


class Test_Class(object):
    def test_one(self):
        assert 2 == 1

    @pytest.mark.run_two
    def testtwo(self):
        assert 2 == 2

    def test_two2(self):
        assert 2 == 2


if __name__ == '__main__':
    pytest.main(['-v','-m','run_one or run_all'])
    
juzi\test_02.py
@pytest.mark.run_all
class TestClass(object):
    def test_one(self):
        assert 2 == 1


    def test_two(self):
        assert 2 == 2


    def test_two2(self):
        assert 2 == 2


if __name__ == '__main__':
    pytest.main(['-v','-m','run_one or run_all'])
 
 import pytest

test_03.py
class TestClass(object):
    @pytest.mark.run_one
    def test_one(self):
        assert 2 == 1

    def test_two(self):
        assert 2 == 2


    def test_two2(self):
        assert 2 == 2


if __name__ == '__main__':
    pytest.main(['-v','-m','run_one or run_all'])
    
test_04.py    
class TestClass(object):
    def test_onqq(self):
        assert 2 == 1


    def test_two(self):
        assert 2 == 2

    @pytest.mark.two2
    def test_two2(self):
        assert 2 == 2


if __name__ == '__main__':
    pytest.main(['-v','-m','run_one or run_all'])

执行匹配类或函数装饰器里，标记名为run_one或run_all的测试用例，可以看到匹配运行了4条用例

pytest.main(['-v','-m','run_one or run_all'])

if __name__ == '__main__':
    pytest.main(['-v','-m','run_one or run_all'])
    
"C:\Program Files\Python35\python.exe" C:/Users/wangli/PycharmProjects/untitled/test_04.py
============================= test session starts =============================
platform win32 -- Python 3.5.2, pytest-6.1.1, py-1.9.0, pluggy-0.13.1 -- C:\Program Files\Python35\python.exe
cachedir: .pytest_cache
metadata: {'JAVA_HOME': 'C:\\Program Files\\Java\\jdk1.8.0_101', 'Platform': 'Windows-10-10.0.18362-SP0', 'Python': '3.5.2', 'Plugins': {'allure-pytest': '2.8.18', 'html': '1.22.0', 'metadata': '1.8.0', 'rerunfailures': '9.1.1'}, 'Packages': {'pytest': '6.1.1', 'pluggy': '0.13.1', 'py': '1.9.0'}}
rootdir: C:\Users\wangli\PycharmProjects\untitled
plugins: allure-pytest-2.8.18, html-1.22.0, metadata-1.8.0, rerunfailures-9.1.1
collecting ... collected 12 items / 8 deselected / 4 selected

test_03.py::TestClass::test_one FAILED                                   [ 25%]
juzi/test_02.py::TestClass::test_one FAILED                              [ 50%]
juzi/test_02.py::TestClass::test_two PASSED                              [ 75%]
juzi/test_02.py::TestClass::test_two2 PASSED                             [100%]

================================== FAILURES ===================================
_____________________________ TestClass.test_one ______________________________

self = <test_03.TestClass object at 0x00000232EDB1BF60>

    @pytest.mark.run_one
    def test_one(self):
>       assert 2 == 1
E       assert 2 == 1
E         +2
E         -1

test_03.py:7: AssertionError
_____________________________ TestClass.test_one ______________________________

self = <juzi.test_02.TestClass object at 0x00000232EDB0B080>

    def test_one(self):
>       assert 2 == 1
E       assert 2 == 1
E         +2
E         -1

juzi\test_02.py:6: AssertionError
============================== warnings summary ===============================
test_03.py:5
  C:\Users\wangli\PycharmProjects\untitled\test_03.py:5: PytestUnknownMarkWarning: Unknown pytest.mark.run_one - is this a typo?  You can register custom marks to avoid this warning - for details, see https://docs.pytest.org/en/stable/mark.html
    @pytest.mark.run_one

test_04.py:12
  C:\Users\wangli\PycharmProjects\untitled\test_04.py:12: PytestUnknownMarkWarning: Unknown pytest.mark.two2 - is this a typo?  You can register custom marks to avoid this warning - for details, see https://docs.pytest.org/en/stable/mark.html
    @pytest.mark.two2

chengzi\test_01.py:8
  C:\Users\wangli\PycharmProjects\untitled\chengzi\test_01.py:8: PytestUnknownMarkWarning: Unknown pytest.mark.run_two - is this a typo?  You can register custom marks to avoid this warning - for details, see https://docs.pytest.org/en/stable/mark.html
    @pytest.mark.run_two

juzi\test_02.py:3
  C:\Users\wangli\PycharmProjects\untitled\juzi\test_02.py:3: PytestUnknownMarkWarning: Unknown pytest.mark.run_all - is this a typo?  You can register custom marks to avoid this warning - for details, see https://docs.pytest.org/en/stable/mark.html
    @pytest.mark.run_all

-- Docs: https://docs.pytest.org/en/stable/warnings.html
=========================== short test summary info ===========================
FAILED test_03.py::TestClass::test_one - assert 2 == 1
FAILED juzi/test_02.py::TestClass::test_one - assert 2 == 1
============ 2 failed, 2 passed, 8 deselected, 4 warnings in 0.24s ============

Process finished with exit code 0

-V（--verbose）选项

输出更加详细的信息，比如用例所在的包、py文件、类名及用例名称等测试的名字和结果都会显示出来，最明显区别就是每个文件中的测试用例都会占一行（先前是每个文件占一行）

pytest.main(['-v'])

-s选项

允许终端在测试运行时，输出用例中的调式信息，包括任何符合标准的输出流信息，比如print的打印信息等。

pytest.main(['-s'])

测试代码：

test-04.py
import pytest


class TestClass(object):
    def test_one(self):
        print('this is test_one')
        assert 2 == 1

    def test_two(self):
        print('this is test_two')
        assert 2 == 2

    @pytest.mark.two2
    def test_two2(self):
        print('this is test_two2')
        assert 2 == 2


if __name__ == '__main__':
    pytest.main(['-s'])
    
"C:\Program Files\Python35\python.exe" C:/Users/wangli/PycharmProjects/untitled/test_04.py
============================= test session starts =============================
platform win32 -- Python 3.5.2, pytest-6.1.1, py-1.9.0, pluggy-0.13.1
rootdir: C:\Users\wangli\PycharmProjects\untitled
plugins: allure-pytest-2.8.18, html-1.22.0, metadata-1.8.0, rerunfailures-9.1.1
111
collected 12 items

test_03.py F..
test_04.py this is test_one
Fthis is test_two
.this is test_two2
.
chengzi\test_01.py F..
juzi\test_02.py F..

-x选项

debug调试时，我们希望遇到断言失败时，立即全局停止，这时就可以用到-x

pytest.main(['-x','test_04.py'])

测试代码如下：

#设置用例1和用例3断言成功，断言2失败
#执行后，用例1执行了，用例2执行断言失败，脚本停止，用例3没有继续执行
import pytest

class TestClass(object):
    def test_one(self):
        print('this is test_one')
        assert 2 == 2

    def test_two(self):
        print('this is test_two')
        assert 2 == 1

    def test_two2(self):
        print('this is test_two2')
        assert 2 == 2


if __name__ == '__main__':
    pytest.main(['-x','test_04.py'])

"C:\Program Files\Python35\python.exe" C:/Users/wangli/PycharmProjects/untitled/test_04.py
============================= test session starts =============================
platform win32 -- Python 3.5.2, pytest-6.1.1, py-1.9.0, pluggy-0.13.1
rootdir: C:\Users\wangli\PycharmProjects\untitled
plugins: allure-pytest-2.8.18, html-1.22.0, metadata-1.8.0, rerunfailures-9.1.1
collected 3 items

test_04.py .F

================================== FAILURES ===================================
_____________________________ TestClass.test_two ______________________________

self = <test_04.TestClass object at 0x000001465DA2D780>

    def test_two(self):
        print('this is test_two')
>       assert 2 == 1
E       assert 2 == 1

test_04.py:11: AssertionError
---------------------------- Captured stdout call -----------------------------
this is test_two
=========================== short test summary info ===========================
FAILED test_04.py::TestClass::test_two - assert 2 == 1
!!!!!!!!!!!!!!!!!!!!!!!!!! stopping after 1 failures !!!!!!!!!!!!!!!!!!!!!!!!!!
========================= 1 failed, 1 passed in 0.88s =========================

Process finished with exit code 0

--maxfail=num

与-x选项类似，测试用例达到指定失败次数，就会全局停止，不在执行，假设允许pytest失败2次后停止，则可以使用--maxfail=2，明确指定可失败次数。

pytest.main(['--maxfail=2','test_04.py'])

测试代码如下：

#设置用例1和用例2断言失败，用例3断言成功
#使用pytest.main(['--maxfail=2','test_04.py'])
#执行了用例1和用例2，达到2次失败，全局停止，未执行用例3
test_04.py
import pytest


class TestClass(object):
    def test_one(self):
        print('this is test_one')
        assert 2 == 1

    def test_two(self):
        print('this is test_two')
        assert 2 == 1

    @pytest.mark.two2
    def test_two2(self):
        print('this is test_two2')
        assert 2 == 2


if __name__ == '__main__':
    pytest.main(['--maxfail=2','test_04.py'])
    
"C:\Program Files\Python35\python.exe" C:/Users/wangli/PycharmProjects/untitled/test_04.py
============================= test session starts =============================
platform win32 -- Python 3.5.2, pytest-6.1.1, py-1.9.0, pluggy-0.13.1
rootdir: C:\Users\wangli\PycharmProjects\untitled
plugins: allure-pytest-2.8.18, html-1.22.0, metadata-1.8.0, rerunfailures-9.1.1
collected 3 items

test_04.py FF

================================== FAILURES ===================================
_____________________________ TestClass.test_one ______________________________

self = <test_04.TestClass object at 0x000001ACC521D5F8>

    def test_one(self):
        print('this is test_one')
>       assert 2 == 1
E       assert 2 == 1

test_04.py:7: AssertionError
---------------------------- Captured stdout call -----------------------------
this is test_one
_____________________________ TestClass.test_two ______________________________

self = <test_04.TestClass object at 0x000001ACC521A668>

    def test_two(self):
        print('this is test_two')
>       assert 2 == 1
E       assert 2 == 1

test_04.py:11: AssertionError
---------------------------- Captured stdout call -----------------------------
this is test_two
============================== warnings summary ===============================
test_04.py:13
  C:\Users\wangli\PycharmProjects\untitled\test_04.py:13: PytestUnknownMarkWarning: Unknown pytest.mark.two2 - is this a typo?  You can register custom marks to avoid this warning - for details, see https://docs.pytest.org/en/stable/mark.html
    @pytest.mark.two2

-- Docs: https://docs.pytest.org/en/stable/warnings.html
=========================== short test summary info ===========================
FAILED test_04.py::TestClass::test_one - assert 2 == 1
FAILED test_04.py::TestClass::test_two - assert 2 == 1
!!!!!!!!!!!!!!!!!!!!!!!!!! stopping after 2 failures !!!!!!!!!!!!!!!!!!!!!!!!!!
======================== 2 failed, 1 warning in 0.17s =========================

Process finished with exit code 0

--lf（--last-failed）选项

执行上次断言失败的用例A，当用例A一直是断言失败，运行脚本一直只执行用例A；当用例A断言成功后，没有失败的用例了，会执行全部用例，如果又有断言失败的用例，下次会执行运行失败的用例（运行脚本会执行上次断言失败的用例，没有失败用例会执行所有用例）

pytest.main(['--lf','test_04.py'])

#设置test_two用例断言失败，运行j脚本后只跑了test_two用例
import pytest
class TestClass(object):
    def test_one(self):
        print('this is test_one')
        assert 2 == 2

    def test_two(self):
        print('this is test_two')
        assert 2 == 1

    def test_two2(self):
        print('this is test_two2')
        assert 2 == 2


if __name__ == '__main__':
    pytest.main(['--lf','test_04.py'])
    
collected 3 items / 2 deselected / 1 selected
run-last-failure: rerun previous 1 failure

test_04.py F                                                             [100%]

================================== FAILURES ===================================
_____________________________ TestClass.test_two ______________________________

self = <test_04.TestClass object at 0x0000028C5FB3A198>

    def test_two(self):
        print('this is test_two')
>       assert 2 == 1
E       assert 2 == 1

test_04.py:11: AssertionError
---------------------------- Captured stdout call -----------------------------
this is test_two
=========================== short test summary info ===========================
FAILED test_04.py::TestClass::test_two - assert 2 == 1
======================= 1 failed, 2 deselected in 0.15s =======================

Process finished with exit code 0

#把用例test_two改成断言正确的，再次运行脚本，仍执行了test_two用例，发现test_two
# 用例断言成功了
import pytest
class TestClass(object):
    def test_one(self):
        print('this is test_one')
        assert 2 == 2

    def test_two(self):
        print('this is test_two')
        assert 2 == 2

    def test_two2(self):
        print('this is test_two2')
        assert 2 == 2


if __name__ == '__main__':
    pytest.main(['--lf','test_04.py'])
    
collected 3 items / 2 deselected / 1 selected
run-last-failure: rerun previous 1 failure

test_04.py .                                                             [100%]

======================= 1 passed, 2 deselected in 0.09s =======================

Process finished with exit code 0

#再次运行脚本，执行了全部用例
import pytest
class TestClass(object):
    def test_one(self):
        print('this is test_one')
        assert 2 == 2

    def test_two(self):
        print('this is test_two')
        assert 2 == 2

    def test_two2(self):
        print('this is test_two2')
        assert 2 == 2


if __name__ == '__main__':
    pytest.main(['--lf','test_04.py'])
    
collected 3 items
run-last-failure: 13 known failures not in selected tests

test_04.py ...                                                           [100%]

============================== 3 passed in 0.05s ==============================

Process finished with exit code 0

--ff（--failed-first）选项

--ff选项，运行脚本，会优先执行上次断言失败的用例，再依次执行其他用例，直至运行脚本，上次断言失败的用例这次变为断言成功，下次再运行脚本，才会按正常用例顺序依次执行，与--lf选项作用基本相同，不同之处--ff会运行剩下的测试用例。

pytest.main(['-s','--ff','test_04.py'])

# 设置test_two2断言失败，首次运行脚本，未优先执行test_two2，
# 结果test_two2断言失败
import pytest
class TestClass(object):
    def test_one(self):
        print('this is test_one')
        assert 2 == 2

    def test_two(self):
        print('this is test_two')
        assert 2 == 2

    def test_two2(self):
        print('this is test_two2')
        assert 2 == 1


if __name__ == '__main__':
    pytest.main(['-s','--ff','test_04.py'])
    
collected 3 items
run-last-failure: 13 known failures not in selected tests

test_04.py this is test_one
.this is test_two
.this is test_two2
F

================================== FAILURES ===================================
_____________________________ TestClass.test_two2 _____________________________

self = <test_04.TestClass object at 0x000001A124621CF8>

    def test_two2(self):
        print('this is test_two2')
>       assert 2 == 1
E       assert 2 == 1

test_04.py:15: AssertionError
=========================== short test summary info ===========================
FAILED test_04.py::TestClass::test_two2 - assert 2 == 1
========================= 1 failed, 2 passed in 0.17s =========================

Process finished with exit code 0

# 脚本不变，再次运行一次，发现优先执行了上次断言失败的用例test_two2
# 再按顺序依次执行，结果test_two2断言失败
collected 3 items
run-last-failure: rerun previous 1 failure first

test_04.py this is test_two2
Fthis is test_one
.this is test_two
.

================================== FAILURES ===================================
_____________________________ TestClass.test_two2 _____________________________

self = <test_04.TestClass object at 0x000002C5D0F03668>

    def test_two2(self):
        print('this is test_two2')
>       assert 2 == 1
E       assert 2 == 1

test_04.py:15: AssertionError
=========================== short test summary info ===========================
FAILED test_04.py::TestClass::test_two2 - assert 2 == 1
========================= 1 failed, 2 passed in 0.10s =========================

Process finished with exit code 0

# test_two2用例改成断言成功，再次执行脚本，发现还是优先执行了上次断言失败的用例test_two2
# 用例，再按顺序依次执行，结果test_two2断言成功
    def test_two2(self):
        print('this is test_two2')
        assert 2 == 2
        
collected 3 items
run-last-failure: rerun previous 1 failure first

test_04.py this is test_two2
.this is test_one
.this is test_two
.

============================== 3 passed in 0.07s ==============================

Process finished with exit code 0

# 脚本不变，再运行依次脚本，发现未优先执行test_two2用例，因为上次结果
# 没有断言失败的，所有不会优先执行，正常依次执行

collected 3 items
run-last-failure: 13 known failures not in selected tests

test_04.py this is test_one
.this is test_two
.this is test_two2
.

============================== 3 passed in 0.03s ==============================

Process finished with exit code 0

--tb=style选项

捕捉到失败时输出信息的显示方式，某个测试用例失败后，pytest会列举出失败信息，包括失败在哪一行、是什么失败、怎么失败的，此过程称“信息回溯”它对找到问题很有帮助，但有时也会对多余的信息感到厌烦，这时--tb=style选项就有用武之地了，style类型有short、line、no。short模式仅输出assert的一行以及系统判定内容（不显示上下文）；line模式只使用一行输出显示所有的错误信息；no模式则直接屏蔽全部回溯信息

pytest.main(['--tb=no','test_04.py'])，屏蔽全部回溯信息

collected 3 items

test_04.py ..F                                                           [100%]

=========================== short test summary info ===========================
FAILED test_04.py::TestClass::test_two2 - assert 2 == 1
========================= 1 failed, 2 passed in 0.09s =========================

pytest.main(['--tb=line','test_04.py'])，告诉我们错误的位置

collected 3 items

test_04.py ..F                                                           [100%]

================================== FAILURES ===================================
C:\Users\wangli\PycharmProjects\untitled\test_04.py:15: assert 2 == 1
=========================== short test summary info ===========================
FAILED test_04.py::TestClass::test_two2 - assert 2 == 1
========================= 1 failed, 2 passed in 0.19s =========================

Process finished with exit code 0

pytest.main(['--tb=short','test_04.py'])，显示回溯信息比前面两种都详细

collected 3 items

test_04.py ..F                                                           [100%]

================================== FAILURES ===================================
_____________________________ TestClass.test_two2 _____________________________
test_04.py:15: in test_two2
    assert 2 == 1
E   assert 2 == 1
---------------------------- Captured stdout call -----------------------------
this is test_two2
=========================== short test summary info ===========================
FAILED test_04.py::TestClass::test_two2 - assert 2 == 1
========================= 1 failed, 2 passed in 0.42s =========================

Process finished with exit code 0

pytest.main(['--tb=long','test_04.py'])输出最详细的回溯信息

collected 3 items

test_04.py ..F                                                           [100%]

================================== FAILURES ===================================
_____________________________ TestClass.test_two2 _____________________________

self = <test_04.TestClass object at 0x00000229D5D7E8D0>

    def test_two2(self):
        print('this is test_two2')
>       assert 2 == 1
E       assert 2 == 1

test_04.py:15: AssertionError
---------------------------- Captured stdout call -----------------------------
this is test_two2
=========================== short test summary info ===========================
FAILED test_04.py::TestClass::test_two2 - assert 2 == 1
========================= 1 failed, 2 passed in 0.18s =========================

Process finished with exit code 0

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原始发表：2021-07-18，如有侵权请联系 cloudcommunity@tencent.com 删除

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