pytest 用例之间共享变量

1、在setup中创建不可变变量。各个用例和teardown都可以使用，但是不能修改变量。

　　示例如下

#coding:utf-8

import pytest

class Test_share_var(object):
    def setup_class(self):
        print("\nhere is setup_class")
        self.driver = "driver_setup" # setup中创建变量
    def test_step1(self):
        print("\nhere is test_step1")
        self.driver = "driver_step1" # 用例中修改变量
    def test_step2(self):
        print("\nhere is test_step2")
        print("driver:{}".format(self.driver)) # 用例中引用变量
    def teardown_class(self):
        print("\nhere is teardown_class")
        print("driver:{}".format(self.driver)) # teardown中引用变量

if __name__=="__main__":
    args = ["share_var.py::Test_share_var","-sv"]
    pytest.main(args)

结果如下：

python share_var.py
=================================================================== test session starts ====================================================================
platform win32 -- Python 3.8.10, pytest-6.2.5, py-1.11.0, pluggy-1.0.0 -- C:\Users\wangwuhui\AppData\Local\Programs\Python\Python38\python.exe
cachedir: .pytest_cache
metadata: {'Python': '3.8.10', 'Platform': 'Windows-10-10.0.18363-SP0', 'Packages': {'pytest': '6.2.5', 'py': '1.11.0', 'pluggy': '1.0.0'}, 'Plugins': {'allure-pytest': '2.9.45', 'dependency': '0.5.1', 'html': '3.1.1', 'metadata': '1.11.0', 'mock': '3.7.0', 'rerunfailures': '10.2'}, 'JAVA_HOME': 'C:\\Program Files\\Java\\jdk1.8.0_301'}
rootdir: C:\Users\wangwuhui\Desktop
plugins: allure-pytest-2.9.45, dependency-0.5.1, html-3.1.1, metadata-1.11.0, mock-3.7.0, rerunfailures-10.2
collected 2 items

share_var.py::Test_share_var::test_step1
here is setup_class

here is test_step1
PASSED
share_var.py::Test_share_var::test_step2
here is test_step2
driver:driver_setup # 可以引用变量。可以看到值为driver_setup，说明test_step1修改变量值没有成功。
PASSED
here is teardown_class
driver:driver_setup # 可以引用变量。


==================================================================== 2 passed in 0.04s =====================================================================

2、在用例中创建不可变变量，不能共享给其它用例使用。

　　示例如下

#coding:utf-8

import pytest

        
class Test_share_var1(object):
    def setup_class(self):
        print("\nhere is setup_class")
    def test_step1(self):
        print("\nhere is test_step1")
        self.var_step1 = "var_step1" # 在用例中创建变量
    def test_step2(self):
        print("\nhere is test_step2")
        print("var_step1:{}".format(self.var_step1)) # 在用例中引用变量
    def teardown_class(self):
        print("\nhere is teardown_class")
        print("var_step1:{}".format(self.var_step1))

if __name__=="__main__":
    args = ["share_var.py::Test_share_var1","-sv"]
    pytest.main(args)

结果如下：

python share_var.py
=================================================================== test session starts ====================================================================
platform win32 -- Python 3.8.10, pytest-6.2.5, py-1.11.0, pluggy-1.0.0 -- C:\Users\wangwuhui\AppData\Local\Programs\Python\Python38\python.exe
cachedir: .pytest_cache
metadata: {'Python': '3.8.10', 'Platform': 'Windows-10-10.0.18363-SP0', 'Packages': {'pytest': '6.2.5', 'py': '1.11.0', 'pluggy': '1.0.0'}, 'Plugins': {'allure-pytest': '2.9.45', 'dependency': '0.5.1', 'html': '3.1.1', 'metadata': '1.11.0', 'mock': '3.7.0', 'rerunfailures': '10.2'}, 'JAVA_HOME': 'C:\\Program Files\\Java\\jdk1.8.0_301'}
rootdir: C:\Users\wangwuhui\Desktop
plugins: allure-pytest-2.9.45, dependency-0.5.1, html-3.1.1, metadata-1.11.0, mock-3.7.0, rerunfailures-10.2
collected 2 items

share_var.py::Test_share_var1::test_step1
here is setup_class

here is test_step1
PASSED
share_var.py::Test_share_var1::test_step2
here is test_step2
FAILED
here is teardown_class

share_var.py::Test_share_var1::test_step2 ERROR

========================================================================== ERRORS ==========================================================================
_____________________________________________________ ERROR at teardown of Test_share_var1.test_step2 ______________________________________________________

self = <class 'share_var.Test_share_var1'>

    def teardown_class(self):
        print("\nhere is teardown_class")
>       print("var_step1:{}".format(self.var_step1))
E       AttributeError: type object 'Test_share_var1' has no attribute 'var_step1'

share_var.py:30: AttributeError
========================================================================= FAILURES =========================================================================
________________________________________________________________ Test_share_var1.test_step2 ________________________________________________________________

self = <share_var.Test_share_var1 object at 0x000001B8B0274070>

    def test_step2(self):
        print("\nhere is test_step2")
>       print("var_step1:{}".format(self.var_step1))
E       AttributeError: 'Test_share_var1' object has no attribute 'var_step1'

share_var.py:27: AttributeError
================================================================= short test summary info ==================================================================
FAILED share_var.py::Test_share_var1::test_step2 - AttributeError: 'Test_share_var1' object has no attribute 'var_step1'
ERROR share_var.py::Test_share_var1::test_step2 - AttributeError: type object 'Test_share_var1' has no attribute 'var_step1'
=========================================================== 1 failed, 1 passed, 1 error in 0.51s ===========================================================

报错信息

AttributeError: type object 'Test_share_var1' has no attribute 'var_step1'说明，test_step1中创建的变量不能共享给

在test_step2中引用。

3、在setup中创建可变变量。各个用例和teardown都可以使用，还能修改变量。

　　示例如下

#coding:utf-8

import pytest

class Test_share_var3(object):
    def setup_class(self):
        print("\nhere is setup_class")
        self.inner_var = {"var1":"a","var2":"b"} # 在setup中创建可变变量
    def test_step1(self):
        print("\nhere is test_step1")
        self.inner_var['var1']="var_step1" # 在test_step1中修改可变变量
    def test_step2(self):
        print("\nhere is test_step2")
        print("var1:{}".format(self.inner_var['var1'])) # 在test_step2中引用可变变量
        print("var2:{}".format(self.inner_var['var2']))
    def teardown_class(self):
        print("\nhere is teardown_class")
        print("var1:{}".format(self.inner_var['var1'])) # 在teardown中引用可变变量
        print("var2:{}".format(self.inner_var['var2']))

if __name__=="__main__":
    args = ["share_var.py::Test_share_var3","-sv"]
    pytest.main(args)

结果如下：

python share_var.py
=================================================================== test session starts ====================================================================
platform win32 -- Python 3.8.10, pytest-6.2.5, py-1.11.0, pluggy-1.0.0 -- C:\Users\wangwuhui\AppData\Local\Programs\Python\Python38\python.exe
cachedir: .pytest_cache
metadata: {'Python': '3.8.10', 'Platform': 'Windows-10-10.0.18363-SP0', 'Packages': {'pytest': '6.2.5', 'py': '1.11.0', 'pluggy': '1.0.0'}, 'Plugins': {'allure-pytest': '2.9.45', 'dependency': '0.5.1', 'html': '3.1.1', 'metadata': '1.11.0', 'mock': '3.7.0', 'rerunfailures': '10.2'}, 'JAVA_HOME': 'C:\\Program Files\\Java\\jdk1.8.0_301'}
rootdir: C:\Users\wangwuhui\Desktop
plugins: allure-pytest-2.9.45, dependency-0.5.1, html-3.1.1, metadata-1.11.0, mock-3.7.0, rerunfailures-10.2
collected 2 items

share_var.py::Test_share_var3::test_step1
here is setup_class

here is test_step1
PASSED
share_var.py::Test_share_var3::test_step2
here is test_step2
var1:var_step1 # var1的值从a变为var_step1，说明用例可以引用和修改共享的可变变量
var2:b
PASSED
here is teardown_class
var1:var_step1 # 说明teardown可以引用共享的可变变量
var2:b


==================================================================== 2 passed in 0.06s =====================================================================