详解pytest分布式执行插件 pytest-xdist 的高级用法

想要使用多个CPU核心来进行测试，可以使用 -n 参数( 或者 --numprocesses)
(使用8个核心来跑测试用例)

pytest -n 8

使用 -n auto 参数可以利用电脑的所有核心来跑测试用例
测试时使用的算法可以根据--dist命令参数定制：

• --dist load(默认选项)：给每个CPU核心随机分配用例，不保证执行顺序。

• --dist loadscope：对于测试函数，测试按模块分组，对于测试方法，测试按类分组。每组作为一个整体分配给可用的worker。这保证了组中的所有测试都在同一进程中运行。如果的模块级或类级fixtures，这将非常有用。按类分组优先于按模块分组。

• --dist loadfile: 测试用例按其所在文件分组。每组作为一个整体分配给可用的worker。这保证了文件中的所有测试都在同一个辅助进程中运行。

• --dist loadgroup: 测试按xdist_group标记分组。每组作为一个整体分配给可用的执行器。这保证了具有相同xdist_ group名称的所有测试都在同一个worker中运行。

@pytest.mark.xdist_group(name="group1")
def test1():
   pass

class TestA:
   @pytest.mark.xdist_group("group1")
   def test2():
       pass-

这将确保test1和TestA:：test2将在同一个worker中运行。没有xdist_ group标记的测试在--dist=load模式下正常运行。

• --dist no：正常的pytest执行模式，一次运行一个测试（完全没有分发）。

例子：
项目目录结构

xdist_test.py

import logging
import pytest
class TestXdist(object):
   @pytest.mark.xdist_group("group1")
   def test_one(self):
       logging.info("1")
       assert True
   @pytest.mark.xdist_group("group1")
   def test_two(self):
       logging.info("2")
       assert True
   @pytest.mark.xdist_group("group2")
   def test_three(self):
       logging.info("3")
       assert True
   @pytest.mark.xdist_group("group2")
   def test_four(self):
       logging.info("4")
       assert True

xdist_dummy_test.py

import logging
import pytest
class TestXdist(object):
   @pytest.mark.run(order=1)
   @pytest.mark.xdist_group("group1")
   def test_dummy_one(self):
       logging.info("d1")
       assert True
   @pytest.mark.xdist_group("group1")
   @pytest.mark.run(order=2)
   def test_dummy_two(self):
       logging.info("d2")
       assert True
   @pytest.mark.run(order=3)
   @pytest.mark.xdist_group("group2")
   def test_dummy_three(self):
       logging.info("d3")
       assert True
   @pytest.mark.xdist_group("group2")
   @pytest.mark.run(order=4)
   def test_dummy_four(self):
       logging.info("d4")
       assert True

(venv) ?  pytest pytest -n auto --dist loadscope
=========================================================================== test session starts ===========================================================================
platform darwin -- Python 3.8.9, pytest-7.1.2, pluggy-1.0.0
rootdir: /Users/spock/PycharmProjects/pytest, configfile: pytest.ini
plugins: xdist-2.5.0, forked-1.4.0, ordering-0.6
[gw0] Python 3.8.9 (default, May 17 2022, 12:55:41)  -- [Clang 13.1.6 (clang-1316.0.21.2.5)]
[gw1] Python 3.8.9 (default, May 17 2022, 12:55:41)  -- [Clang 13.1.6 (clang-1316.0.21.2.5)]
[gw2] Python 3.8.9 (default, May 17 2022, 12:55:41)  -- [Clang 13.1.6 (clang-1316.0.21.2.5)]
[gw3] Python 3.8.9 (default, May 17 2022, 12:55:41)  -- [Clang 13.1.6 (clang-1316.0.21.2.5)]
[gw4] Python 3.8.9 (default, May 17 2022, 12:55:41)  -- [Clang 13.1.6 (clang-1316.0.21.2.5)]
[gw5] Python 3.8.9 (default, May 17 2022, 12:55:41)  -- [Clang 13.1.6 (clang-1316.0.21.2.5)]
[gw6] Python 3.8.9 (default, May 17 2022, 12:55:41)  -- [Clang 13.1.6 (clang-1316.0.21.2.5)]
[gw7] Python 3.8.9 (default, May 17 2022, 12:55:41)  -- [Clang 13.1.6 (clang-1316.0.21.2.5)]
gw0 [8] / gw1 [8] / gw2 [8] / gw3 [8] / gw4 [8] / gw5 [8] / gw6 [8] / gw7 [8]
scheduling tests via LoadScopeScheduling

test2/xdist_dummy_test.py::TestXdist::test_dummy_one
test/xdist_test.py::TestXdist::test_one
[gw0] [ 12％] PASSED test2/xdist_dummy_test.py::TestXdist::test_dummy_one
[gw1] [ 25％] PASSED test/xdist_test.py::TestXdist::test_one
test2/xdist_dummy_test.py::TestXdist::test_dummy_two
test/xdist_test.py::TestXdist::test_two
[gw1] [ 37％] PASSED test/xdist_test.py::TestXdist::test_two
test/xdist_test.py::TestXdist::test_three
[gw0] [ 50％] PASSED test2/xdist_dummy_test.py::TestXdist::test_dummy_two
test2/xdist_dummy_test.py::TestXdist::test_dummy_three
[gw1] [ 62％] PASSED test/xdist_test.py::TestXdist::test_three
test/xdist_test.py::TestXdist::test_four
[gw0] [ 75％] PASSED test2/xdist_dummy_test.py::TestXdist::test_dummy_three
test2/xdist_dummy_test.py::TestXdist::test_dummy_four
[gw1] [ 87％] PASSED test/xdist_test.py::TestXdist::test_four
[gw0] [100％] PASSED test2/xdist_dummy_test.py::TestXdist::test_dummy_four
============================================================================ 8 passed in 0.40s ============================================================================

(venv) ?  pytest pytest -n auto --dist loadfile
=========================================================================== test session starts ===========================================================================
platform darwin -- Python 3.8.9, pytest-7.1.2, pluggy-1.0.0
rootdir: /Users/spock/PycharmProjects/pytest, configfile: pytest.ini
plugins: xdist-2.5.0, forked-1.4.0, ordering-0.6
[gw0] Python 3.8.9 (default, May 17 2022, 12:55:41)  -- [Clang 13.1.6 (clang-1316.0.21.2.5)]
[gw1] Python 3.8.9 (default, May 17 2022, 12:55:41)  -- [Clang 13.1.6 (clang-1316.0.21.2.5)]
[gw2] Python 3.8.9 (default, May 17 2022, 12:55:41)  -- [Clang 13.1.6 (clang-1316.0.21.2.5)]
[gw3] Python 3.8.9 (default, May 17 2022, 12:55:41)  -- [Clang 13.1.6 (clang-1316.0.21.2.5)]
[gw4] Python 3.8.9 (default, May 17 2022, 12:55:41)  -- [Clang 13.1.6 (clang-1316.0.21.2.5)]
[gw5] Python 3.8.9 (default, May 17 2022, 12:55:41)  -- [Clang 13.1.6 (clang-1316.0.21.2.5)]
[gw6] Python 3.8.9 (default, May 17 2022, 12:55:41)  -- [Clang 13.1.6 (clang-1316.0.21.2.5)]
[gw7] Python 3.8.9 (default, May 17 2022, 12:55:41)  -- [Clang 13.1.6 (clang-1316.0.21.2.5)]
gw0 [8] / gw1 [8] / gw2 [8] / gw3 [8] / gw4 [8] / gw5 [8] / gw6 [8] / gw7 [8]
scheduling tests via LoadFileScheduling

test/xdist_test.py::TestXdist::test_one
test2/xdist_dummy_test.py::TestXdist::test_dummy_one
[gw1] [ 12％] PASSED test/xdist_test.py::TestXdist::test_one
[gw0] [ 25％] PASSED test2/xdist_dummy_test.py::TestXdist::test_dummy_one
test/xdist_test.py::TestXdist::test_two
test2/xdist_dummy_test.py::TestXdist::test_dummy_two
[gw1] [ 37％] PASSED test/xdist_test.py::TestXdist::test_two
[gw0] [ 50％] PASSED test2/xdist_dummy_test.py::TestXdist::test_dummy_two
test2/xdist_dummy_test.py::TestXdist::test_dummy_three
test/xdist_test.py::TestXdist::test_three
[gw1] [ 62％] PASSED test/xdist_test.py::TestXdist::test_three
[gw0] [ 75％] PASSED test2/xdist_dummy_test.py::TestXdist::test_dummy_three
test2/xdist_dummy_test.py::TestXdist::test_dummy_four
test/xdist_test.py::TestXdist::test_four
[gw1] [ 87％] PASSED test/xdist_test.py::TestXdist::test_four
[gw0] [100％] PASSED test2/xdist_dummy_test.py::TestXdist::test_dummy_four

============================================================================ 8 passed in 0.38s ============================================================================

(venv) ?  pytest pytest -n auto --dist loadgroup
=========================================================================== test session starts ===========================================================================
platform darwin -- Python 3.8.9, pytest-7.1.2, pluggy-1.0.0
rootdir: /Users/spock/PycharmProjects/pytest, configfile: pytest.ini
plugins: xdist-2.5.0, forked-1.4.0, ordering-0.6
[gw0] Python 3.8.9 (default, May 17 2022, 12:55:41)  -- [Clang 13.1.6 (clang-1316.0.21.2.5)]
[gw1] Python 3.8.9 (default, May 17 2022, 12:55:41)  -- [Clang 13.1.6 (clang-1316.0.21.2.5)]
[gw2] Python 3.8.9 (default, May 17 2022, 12:55:41)  -- [Clang 13.1.6 (clang-1316.0.21.2.5)]
[gw3] Python 3.8.9 (default, May 17 2022, 12:55:41)  -- [Clang 13.1.6 (clang-1316.0.21.2.5)]
[gw4] Python 3.8.9 (default, May 17 2022, 12:55:41)  -- [Clang 13.1.6 (clang-1316.0.21.2.5)]
[gw5] Python 3.8.9 (default, May 17 2022, 12:55:41)  -- [Clang 13.1.6 (clang-1316.0.21.2.5)]
[gw6] Python 3.8.9 (default, May 17 2022, 12:55:41)  -- [Clang 13.1.6 (clang-1316.0.21.2.5)]
[gw7] Python 3.8.9 (default, May 17 2022, 12:55:41)  -- [Clang 13.1.6 (clang-1316.0.21.2.5)]
gw0 [8] / gw1 [8] / gw2 [8] / gw3 [8] / gw4 [8] / gw5 [8] / gw6 [8] / gw7 [8]
scheduling tests via LoadGroupScheduling

test2/xdist_dummy_test.py::TestXdist::test_dummy_three@group2
test2/xdist_dummy_test.py::TestXdist::test_dummy_one@group1
[gw1] [ 12％] PASSED test2/xdist_dummy_test.py::TestXdist::test_dummy_three@group2
test2/xdist_dummy_test.py::TestXdist::test_dummy_four@group2
[gw0] [ 25％] PASSED test2/xdist_dummy_test.py::TestXdist::test_dummy_one@group1
[gw1] [ 37％] PASSED test2/xdist_dummy_test.py::TestXdist::test_dummy_four@group2
test2/xdist_dummy_test.py::TestXdist::test_dummy_two@group1
[gw0] [ 50％] PASSED test2/xdist_dummy_test.py::TestXdist::test_dummy_two@group1
test/xdist_test.py::TestXdist::test_three@group2
[gw1] [ 62％] PASSED test/xdist_test.py::TestXdist::test_three@group2
test/xdist_test.py::TestXdist::test_four@group2
[gw1] [ 75％] PASSED test/xdist_test.py::TestXdist::test_four@group2
test/xdist_test.py::TestXdist::test_one@group1
[gw0] [ 87％] PASSED test/xdist_test.py::TestXdist::test_one@group1
test/xdist_test.py::TestXdist::test_two@group1
[gw0] [100％] PASSED test/xdist_test.py::TestXdist::test_two@group1

============================================================================ 8 passed in 0.40s ============================================================================

来源：https://www.cnblogs.com/SoonPan/archive/2022/08/12/16578391.html