串口代码：

import serial
import serial.tools.list_ports

class Communication():

    #初始化
    def __init__(self,com,bps,timeout):
        self.port = com
        self.bps = bps
        self.timeout = timeout
        global Ret
        try:
            # 打开串口，并得到串口对象
             self.main_engine= serial.Serial(self.port,self.bps,timeout=self.timeout)
            # 判断是否打开成功
             if (self.main_engine.is_open):
               Ret = True
        except Exception as e:
            print("---异常---：", e)


    # 打印设备基本信息
    def Print_Name(self):
        print(self.main_engine.name) #设备名字
        print(self.main_engine.port)#读或者写端口
        print(self.main_engine.baudrate)#波特率
        ‘‘‘print(self.main_engine.bytesize)#字节大小
        print(self.main_engine.parity)#校验位
        print(self.main_engine.stopbits)#停止位
        print(self.main_engine.timeout)#读超时设置
        print(self.main_engine.writeTimeout)#写超时
        print(self.main_engine.xonxoff)#软件流控
        print(self.main_engine.rtscts)#软件流控
        print(self.main_engine.dsrdtr)#硬件流控
        print(self.main_engine.interCharTimeout)#字符间隔超时‘‘‘

    #打开串口
    def Open_Engine(self):
        self.main_engine.open()

    #关闭串口
    def Close_Engine(self):
        self.main_engine.close()
        print(self.main_engine.is_open)  # 检验串口是否打开

    # 打印可用串口列表
    @staticmethod
    def Print_Used_Com():
        port_list = list(serial.tools.list_ports.comports())
        print(port_list)





    #接收指定大小的数据
    #从串口读size个字节。如果指定超时，则可能在超时后返回较少的字节；如果没有指定超时，则会一直等到收完指定的字节数。
    def Read_Size(self,size):
        return self.main_engine.read(size=size)

    #接收一行数据
    # 使用readline()时应该注意：打开串口时应该指定超时，否则如果串口没有收到新行，则会一直等待。
    # 如果没有超时，readline会报异常。
    def Read_Line(self):
        return self.main_engine.readline()

    #发数据
    def Send_data(self,data):
        self.main_engine.write(data)



    #接收数据
    #一个整型数据占两个字节
    #一个字符占一个字节
    def Seed_SELF(self,data):
        self.main_engine.write(data.encode("utf-8"))  # 写数据
        print("写总字节数:", data)

    def Recive_data(self):
        # 循环接收数据，此为死循环，可用线程实现
        print("开始接收数据：")
        #self.main_engine.write(‘11111‘.encode("utf-8"))
        while True:
            if self.main_engine.in_waiting:
                str = self.main_engine.read(self.main_engine.in_waiting).decode("utf-8")
                if (str[0:5] == "exit"):
                    break
                else:
                    print("收到数据：", str)
                    break




Communication.Print_Used_Com()
Ret =False #是否创建成功标志

Engine1 = Communication("com4", 115200, 5)
Engine1.Print_Name

if __name__ == "__main__":

    if (Ret):
        #rett = Engine1.Send_data(‘1111‘)
        Engine1.Send_data("00055".encode("utf-8"))
        Engine1.Recive_data()
        Engine1.Send_data("1110".encode("utf-8"))
        Engine1.Recive_data()
        Engine1.Close_Engine()

文件名为qq2021_7_7通过串口的短接（tx和rx相连）实现串口的实现和测试

import unittest
from unittest import mock
from qq2021_7_7 import Communication

class MyTestCase(unittest.TestCase):
    def test_COM(self):
        com01 = Communication("com4", 115200, 5)
        com01.com_test = mock.Mock(
                         return_value={"Ret": True, "COM": ‘COM4‘, "timeout": 5})
        com = ‘COM3‘
        bps = 9600
        timeout = 4
        res = com01.com_test(com, bps, timeout)
        print(res)
        self.assertEqual(res["Ret"], True)

    def test_Open_com(self):
        self.Open_Engine = mock.Mock(
            return_value=True)
        self.assertEqual(self.Open_Engine(), True)

    def test_Send_com(self):
        self.Send_data = mock.Mock(
            return_value = 111)
        self.assertEqual(self.Send_data(), 111)

    def test_Recive_data(self):
        self.Recive_data = mock.Mock(
                                     return_value = 111)
        res = self.Recive_data(111)
        self.assertEqual(res, 111)

if __name__ == ‘__main__‘:
    unittest.main()

通过简单的单元测试实现串口的检测，其中send的返回值和recive的返回值是自己臆想的。后面会改进。

unittest的简单串口测试