pytest实际上是python自带测试框架unittest的扩展，那么pytest是如何实现unittest中的setup和teardown的呢？
pytest初始化的类别和作用域
- 模块级别（Module level setup/teardown）：作用于一个模块内的所有class和def，对于所有class和def，setup和teardown只执行一次
def setup_module(module):
""" setup any state specific to the execution of the given module."""
def teardown_module(module):
""" teardown any state that was previously setup with a setup_module
method.
"""
- 类级别（Class level setup/teardown）：作用于一个class内中的所有test,所有用例只执行一次setup，当所有用例执行完成后，才会执行teardown
@classmethod
def setup_class(cls):
""" setup any state specific to the execution of the given class (which
usually contains tests).
"""
@classmethod
def teardown_class(cls):
""" teardown any state that was previously setup with a call to
setup_class.
"""
- 方法和函数级别（Method and function level setup/teardown）：作用于单个测试用例，若用例没有执行（如被skip了）或失败了，则不会执行teardown
def setup_method(self, method):
""" setup any state tied to the execution of the given method in a
class. setup_method is invoked for every test method of a class.
"""
def teardown_method(self, method):
""" teardown any state that was previously setup with a setup_method
call.
"""
若用例直接写在模块中，而不是在类中，则用：
def setup_function(function):
""" setup any state tied to the execution of the given function.
Invoked for every test function in the module.
"""
def teardown_function(function):
""" teardown any state that was previously setup with a setup_function
call.
"""
- pytest.fixture()装饰函数，结合yield实现初始化和teardown
举个例子(pytest）文档中的：
import smtplib
import pytest
@pytest.fixture(scope="module")
def smtp():
smtp = smtplib.SMTP("smtp.gmail.com", 587, timeout=5)
yield smtp # provide the fixture value
print("teardown smtp")
smtp.close()
运行结果：
$ pytest -s -q --tb=no
FFteardown smtp
2 failed in 0.12 seconds
pytest用例初始化操作的示例
为了体现初始化和环境恢复，本节演示采用邮件发送的脚本，可查看邮件发送的脚本：python发送邮件脚本或者参考文章：SMTP发送邮件。
1、setup_method(self, method)
- 在test_method.py中构建了3个测试用例，每个用例在执行前后都会执行setup_method/teardown_method连接smtp和断开smtp。
import smtplib
from email.mime.text import MIMEText
from email.header import Header
from email.mime.multipart import MIMEMultipart
import pytest
class TestSmtp():
# 发件人和收件人,换成你自己的发件人、收件人qq号
sender = "sender@qq.com"
receivers = "rece@qq.com"
# 邮箱服务器
smtpserver = "smtp.qq.com"
smtpport = 465
# 连接邮箱服务器，qq邮箱和密码,换成自己的
username = "sendr@qq.com"
password = "qq mail's password"
smtp = smtplib.SMTP_SSL()
def setup_method(self, method):
self.smtp.connect(self.smtpserver, self.smtpport)
self.smtp.login(self.username, self.password)
print("成功登录")
def teardown_method(self, method):
self.smtp.quit()
print("断开连接")
def test_send_text(self):
# 邮件发送、接收人员，邮件标题、正文
msg = MIMEText("微信公众号号：开源优测", "plain", "utf-8")
msg["From"] = self.sender
msg["To"] = self.receivers
msg["Subject"] = Header("开源优测_DeepTest_from_chenlele_text", "utf-8")
# 发送邮件
self.smtp.sendmail(self.sender, self.receivers, msg.as_string())
def test_send_html(self):
msg = MIMEText("<p>微信公众号号：开源优测</p><a href='http://www.testingunion.com'>开源优测社区</a>>",
"html",
"utf-8")
msg["From"] = self.sender
msg["To"] = self.receivers
msg["Subject"] = Header("开源优测_DeepTest_from_chenlele_html", "utf-8")
# 发送邮件
self.smtp.sendmail(self.sender, self.receivers, msg.as_string())
def test_send_attchment(self):
# 邮件格式说明、发送、接收人员信息、邮件标题
msg = MIMEMultipart()
msg["From"] = self.sender
msg["To"] = self.receivers
msg["Subject"] = Header("开源优测_DeepTest_from_chenlele", "utf-8")
# 构建带附件的邮件正文
msg.attach(MIMEText("微信公众号：开源优测", "plain", "utf-8"))
# 构造附件,多个附件同理
attach1 = MIMEText(open("judge_leap.json", 'rb').read(), "base64", "utf-8")
attach1["Content-Type"] = "application/octet-stream"
# 这里filename随意写，将会在邮件中显示
attach1["Content-Disposition"] = "attrachment;filename=code.py"
# 关联附件到正文
msg.attach(attach1)
# 发送邮件
self.smtp.sendmail(self.sender, self.receivers, msg.as_string())
-
查看结果，采用pytest -s -q 运行，-s 可以查看打印信息，-q减少输出信息：
test_method结果.png
2、setup_class(cls)
- 作用于class的setup_class/teardown_class，类中所有的用例只会执行一次，如图所示；
- ps:用例与test_method.py的一致，参考上一串代码。
test_class.png
3、setup_module(module)
- setup_module/teardown_module在一个模块内，只会执行一次，作用于模块内的所有用例
- 示例中构建了2个class和1个def，共4个用例，可以看到，4个用例只执行了一次module
test_module结果.png
test_module.py
import smtplib
from email.mime.text import MIMEText
from email.header import Header
from email.mime.multipart import MIMEMultipart
import pytest
info = {"sender": "your@qq.com",
"receivers": "yourother@qq.com",
"smtpserver": "smtp.qq.com",
"smtpport": 465,
"username":"your@qq.com",
"password": "yourpassword",
"smtp": smtplib.SMTP_SSL()}
def setup_module(module):
info["smtp"].connect(info["smtpserver"], info["smtpport"])
info["smtp"].login(info["username"], info["password"])
print("成功登录")
def teardown_module(module):
info["smtp"].quit()
print("断开连接")
class TestSendText():
def test_send_text(self):
# 邮件发送、接收人员，邮件标题、正文
msg = MIMEText("微信公众号号：开源优测", "plain", "utf-8")
msg["From"] =info["sender"]
msg["To"] = info["receivers"]
msg["Subject"] = Header("开源优测_DeepTest_from_chenlele_text", "utf-8")
# 发送邮件
info["smtp"].sendmail(info["sender"], info["receivers"], msg.as_string())
def test_send_html(self):
msg = MIMEText("<p>微信公众号号：开源优测</p><a href='http://www.testingunion.com'>开源优测社区</a>>",
"html",
"utf-8")
msg["From"] = info["sender"]
msg["To"] = info["receivers"]
msg["Subject"] = Header("开源优测_DeepTest_from_chenlele_html", "utf-8")
# 发送邮件
info["smtp"].sendmail(info["sender"], info["receivers"], msg.as_string())
class TestSendAttach():
def test_send_attchment(self):
# 邮件格式说明、发送、接收人员信息、邮件标题
msg = MIMEMultipart()
msg["From"] = info["sender"]
msg["To"] = info["receivers"]
msg["Subject"] = Header("开源优测_DeepTest_from_chenlele", "utf-8")
# 构建带附件的邮件正文
msg.attach(MIMEText("微信公众号：开源优测", "plain", "utf-8"))
# 构造附件,多个附件同理
attach1 = MIMEText(open("judge_leap.json", 'rb').read(), "base64", "utf-8")
attach1["Content-Type"] = "application/octet-stream"
# 这里filename随意写，将会在邮件中显示
attach1["Content-Disposition"] = "attrachment;filename=code.py"
# 关联附件到正文
msg.attach(attach1)
# 发送邮件
info["smtp"].sendmail(info["sender"], info["receivers"], msg.as_string())
def test_send_text_out():
# 邮件发送、接收人员，邮件标题、正文
msg = MIMEText("微信公众号号：开源优测", "plain", "utf-8")
msg["From"] =info["sender"]
msg["To"] = info["receivers"]
msg["Subject"] = Header("class外的用例执行", "utf-8")
# 发送邮件
info["smtp"].sendmail(info["sender"], info["receivers"], msg.as_string())
4、pytest.fixture()
- pytest.fixture采用yield实现setup和teardown操作，yield提供的参数为函数名称
- 与setup_module类似，pytest.fixture可作用于一个模块内的所有def和class。区别在于，必须将pytest.fixture()装饰的函数作为参数传递给用例。
- pytest.fixture()装饰的函数必须作为参数传递给用例吗？
1）、将class中的smtp_ini都删除，class中的用例执行失败，def用例执行成功；
2）、将class中test_send_text的smtp_ini保留，其余2个删除，class中的用例都执行成功？这是为什么呢？只有1个用力传入了参数，但所有用例都执行成功了。
3）、将class和def中的smtp_ini都删除，用例全部执行失败。 - ps：用例内容与test_module.py的一致，就不粘代码了。
image.png
总结
4种方式的作用域：
- setup_method:仅作用于class用例集中的用例，置于class内,每个用例都会调用一次
- setup_function:作用于独立的def用例，不可作用于class内的用例
- setup_class:作用于class用例集中的用例，置于class内，只在class用例执行的开始执行setup_class,结束时执行teardown_class
- setup_module:作用于模块内的所有用例，置于class外，只在所以用例的开始执行setup_module,结束时执行teardown_module
- pytest.fixture():作用于模块内的所有用例，但需要传递装饰函数为参数，可置于class内或class外
