标签：expect 就是 dna xpl file difflib class 测试用例 data
众所周知，在单元测试框架中引入ddt，可以将一组数据分解为多组数据，从而实现一条数据对应一个测试用例。但是除此之外，有没有别的办法来实现这个目的呢？
1. 创建一个被测函数math_method.py
class MethMethod(): def add_test(self,a,b): return (a+b)
2. 创建测试用例test_math_method.py
import unittest from homework.math_method import MethMethod #测试类 class TestMathMethod(unittest.TestCase): def __init__(self, methodName, a, b, expected): super(TestMethMethod, self).__init__(methodName) self.a = a self.b = b self.expected = expected #测试用例 def test_add(self): try: self.assertEqual(result, self.expected) except Exception: print("出错了") else: print("计算结果是:{}".format(result))
3. 创建测试数据test_data.txt
[{"a":2,"b":3,"expected":5},{"a":-1,"b":-2,"expected":-3},{"a":3,"b":-1,"expected":-2},{"a":-3,"b":-1,"expected":-4}]
4. 创建测试集test_suite.py
import unittest from homework.test_math_method import TestMathMethod import HTMLTestRunnerNew fs= open("test_data.txt") datas = fs.read() datas = eval(datas) print(type(datas)) if __name__ == ‘__main__‘: suite=unittest.TestSuite() for item in datas: suite.addTest(TestMathMethod("test_add", item[‘a‘], item[‘b‘], item[‘expected‘])) file=open("test_report.html","wb+") runner=HTMLTestRunnerNew.HTMLTestRunner(file,title="加法单元测试报告",tester="july") runner.run(suite)
1. 测试用例类中需要定义一个构造函数，这个构造函数继承了父类的属性，也就是unittest.TestCase的methodName参数
同时，在子类中也重写了构造函数，添加了参数a, b, expected，而这三个则是测试用例函数test_add需要用到的
class TestMethMethod(unittest.TestCase): def __init__(self, methodName, a, b, expected): super(TestMethMethod, self).__init__(methodName) self.a = a self.b = b self.expected = expected
请看TestCase的源码
class TestCase(object):
failureException = AssertionError longMessage = True maxDiff = 80*8 # If a string is longer than _diffThreshold, use normal comparison instead # of difflib. See #11763. _diffThreshold = 2**16 # Attribute used by TestSuite for classSetUp _classSetupFailed = False def __init__(self, methodName=‘runTest‘): """Create an instance of the class that will use the named test method when executed. Raises a ValueError if the instance does not have a method with the specified name. """ self._testMethodName = methodName self._outcome = None self._testMethodDoc = ‘No test‘ try: testMethod = getattr(self, methodName) except AttributeError: if methodName != ‘runTest‘: # we allow instantiation with no explicit method name # but not an *incorrect* or missing method name raise ValueError("no such test method in %s: %s" % (self.__class__, methodName)) else: self._testMethodDoc = testMethod.__doc__ self._cleanups = [] self._subtest = None
2. 此时回到测试集中，看下面一段，TestMathMethod类中本来只有一个参数，methodName，也就是测试用例名，但此时的TestMathMethod已经被我们改写了：不仅继承了父类的methodName方法，而且构造函数中新增了三个参数a, b, expected，这样我们在收集测试用例时，可以为TestMathMethod类添加四个参数：methodName, a, b, expected。通过for循环遍历一组数据，这样可以将多组数据作为多个测试用例添加到测试集中
for item in datas: suite.addTest(TestMathMethod("test_add", item[‘a‘], item[‘b‘], item[‘expected‘]))
ddt的方法：简单，因为涉及到装饰器，不易理解
构造函数：略显繁琐，但容易理解
标签：expect 就是 dna xpl file difflib class 测试用例 data
原文地址：https://www.cnblogs.com/cnhkzyy/p/9508358.html
