pytest简介
pytest 是python的一种单元测试框架，它非常的简洁、清晰。
pytest 安装
pip install -U pytest
查看pytest版本
pytest --version
入门
创建、运行第一个 test
test_first.py
def inc(x):
return x + 1
def test_inc():
assert inc(10) == 20
运行 pytest
an@hosta:~/PycharmProjects/testproject/pytest_study$ pytest # 运行命令
========================================================== test session starts ==========================================================
platform linux -- Python 3.5.2, pytest-3.3.2, py-1.5.2, pluggy-0.6.0
rootdir: /home/an/PycharmProjects/testproject/pytest_study, inifile: pytest.ini
plugins: xdist-1.22.0
collected 1 item # 搜集到的测试用例数量
test_cont.py F # F 代表测试出错， [100%] # 测试完成率
=============================================================== FAILURES ================================================================
_______________________________________________________________ test_inc ____________________ # 测试模块名 _______________________________________
def test_inc():
> assert inc(10) == 20 # 报错的位置
E assert 11 == 20 # 报错原因
E + where 11 = inc(10) # 错误的来源
test_cont.py:6: AssertionError
======================================================= 1 failed in 0.04 seconds =============# 测试结果 =======================================
pytest 测试代码中抛出的异常
cont_test.py
import pytest
def inc(x):
return x + 1
def test_inc():
assert inc(10) == 11
def f():
raise SyntaxError()
def test_f():
with pytest.raises(SyntaxError):
f()
运行pytest
an@hosta:~/PycharmProjects/testproject/pytest_study$ pytest
========================================================== test session starts ==========================================================
platform linux -- Python 3.5.2, pytest-3.3.2, py-1.5.2, pluggy-0.6.0
rootdir: /home/an/PycharmProjects/testproject/pytest_study, inifile: pytest.ini
plugins: xdist-1.22.0
collected 2 items # 两个测试用例
cont_test.py .. # 两个 . 表示都测试成功了 F 表示失败 [100%]
======================================================= 2 passed in 0.01 seconds ========= #测试结果 =======================================
另一种方式运行多个测试。构造一个 测试类 里面包含多个测试用例
cont_test.py
import pytest
class TestClass:
def test_one(self):
x = "this"
assert x != "that"
def test_two(self):
x = "hello"
assert hasattr(x, "upper")
def test_three(self):
with pytest.raises(IndexError):
raise IndexError
运行 pytest
运行pytest的退出码
Exit code 0: All tests were collected and passed successfully
Exit code 1: Tests were collected and run but some of the tests failed
Exit code 2: Test execution was interrupted by the user
Exit code 3: Internal error happened while executing tests
Exit code 4: pytest command line usage error
Exit code 5: No tests were collected
指定测试用例失败次数失败之后，就停止测试
pytest -x 在第一次失败之后，就停止运行剩余的测试
pytest --maxfail=2 两次失败之后，就停止运行剩余测试
指定运行测试用例
目录结构
|---pytest_test
|
|---cont_test.py
# 模块内容
cont_test.py
import pytest
def inc(x):
return x + 1
def test_inc():
assert inc(10) == 11
def f():
raise SyntaxError()
@pytest.mark.slow
def test_f():
with pytest.raises(SyntaxError):
f()
class TestClass:
def test_one(self):
x = "t"
assert x == "that"
def test_two(self):
x = "hello"
assert hasattr(x, "pper")
def test_three(self):
with pytest.raises(IndexError):
raise IndexError
-
指定运行目录
pytest pytest_test -
自动搜索运行本目录内的测试模块（以test开头或结尾）
pytest_test$ pytest -
指定运行模块
pytest_test$ pytest cont_test.py -
指定测试函数
pytest_test$ pytest cont_test.py::test_inc -
指定测试类
pytest_test$ pytest cont_test.py::TestClass -
指定测试方法
pytest_test$ pytest cont_test.py::TestClass::test_one -
指定被mark的测试
pytest_test$ pytest -m slow
将结果输出到 XML 文件
pytest --junitxml=/tmp/zz.xml
禁用pytest的扩展
pytest -p no:doctest -p no:django
方法二：
创建一个 pytest.ini 文件
pytest.ini
[pytest]
addopts = -p no:django -p no:forked -p no:xdist-1.22.0 -p no:celery
;禁用扩展
异常
捕获程序中故意引发的异常
def f():
raise SyntaxError()
def test_f():
with pytest.raises(SyntaxError):
f()
指定测试失败的信息
def test_f():
with pytest.raises(SyntaxError, message='this is i expected error'):
pass
——————————————————————————————
------------------------------------------------ generated xml file: /home/an/haha.xml -------------------------------------------------
=============================================================== FAILURES ================================================================
________________________________________________________________ test_f _________________________________________________________________
def test_f():
with pytest.raises(SyntaxError, message='this is i expected error'):
> pass
E Failed: this is i expected error # 正是我们所希望失败
cont_test.py:17: Failed
================================================== 1 failed, 3 passed in 0.06 seconds =====
进一步限定我们所期望的异常，match使用的 python 中 re.search 方法进行匹配
def test_f():
with pytest.raises(ValueError, match=r'.?1'):
raise ValueError("a1")
# 正常
def test_f():
with pytest.raises(ValueError, match=r'.?1'):
raise ValueError("z3")
_____________________________________________
============================================================== FAILURES ================================================================
________________________________________________________________ test_f _________________________________________________________________
def test_f():
with pytest.raises(ValueError, match=r'.?1'):
> raise ValueError("z3")
E ValueError: z3
cont_test.py:17: ValueError
During handling of the above exception, another exception occurred:
def test_f():
with pytest.raises(ValueError, match=r'.?1'):
> raise ValueError("z3")
E AssertionError: Pattern '.?1' not found in 'z3' # 匹配失败
cont_test.py:17: AssertionError
================================================== 1 failed, 3 passed in 0.10 seconds ============