我有一些测试数据，想为每个项目创建一个单元测试。我的第一个想法是这样做的:
import unittest
l = [["foo", "a", "a",], ["bar", "a", "b"], ["lee", "b", "b"]]
class TestSequence(unittest.TestCase):
def testsample(self):
for name, a,b in l:
print "test", name
self.assertEqual(a,b)
if __name__ == '__main__':
unittest.main()
这样做的缺点是它在一个测试中处理所有数据。我想在飞行中为每个项目生成一个测试。有什么建议吗?
当前回答
load_tests是2.7中引入的一种鲜为人知的机制，用于动态创建TestSuite。有了它，您可以轻松地创建参数化测试。
例如:
import unittest
class GeneralTestCase(unittest.TestCase):
def __init__(self, methodName, param1=None, param2=None):
super(GeneralTestCase, self).__init__(methodName)
self.param1 = param1
self.param2 = param2
def runTest(self):
pass # Test that depends on param 1 and 2.
def load_tests(loader, tests, pattern):
test_cases = unittest.TestSuite()
for p1, p2 in [(1, 2), (3, 4)]:
test_cases.addTest(GeneralTestCase('runTest', p1, p2))
return test_cases
该代码将运行load_tests返回的测试套件中的所有测试用例。发现机制不会自动运行其他测试。
或者，您也可以使用此票据所示的继承:http://bugs.python.org/msg151444
其他回答
这实际上与之前的回答中提到的parameterized相同，但具体到unittest:
def sub_test(param_list):
"""Decorates a test case to run it as a set of subtests."""
def decorator(f):
@functools.wraps(f)
def wrapped(self):
for param in param_list:
with self.subTest(**param):
f(self, **param)
return wrapped
return decorator
使用示例:
class TestStuff(unittest.TestCase):
@sub_test([
dict(arg1='a', arg2='b'),
dict(arg1='x', arg2='y'),
])
def test_stuff(self, arg1, arg2):
...
只使用元类，如这里所示;
class DocTestMeta(type):
"""
Test functions are generated in metaclass due to the way some
test loaders work. For example, setupClass() won't get called
unless there are other existing test methods, and will also
prevent unit test loader logic being called before the test
methods have been defined.
"""
def __init__(self, name, bases, attrs):
super(DocTestMeta, self).__init__(name, bases, attrs)
def __new__(cls, name, bases, attrs):
def func(self):
"""Inner test method goes here"""
self.assertTrue(1)
func.__name__ = 'test_sample'
attrs[func.__name__] = func
return super(DocTestMeta, cls).__new__(cls, name, bases, attrs)
class ExampleTestCase(TestCase):
"""Our example test case, with no methods defined"""
__metaclass__ = DocTestMeta
输出:
test_sample (ExampleTestCase) ... OK
前几天我在查看radon的源代码时遇到了ParamUnittest (GitHub存储库中的使用示例)。它应该与扩展TestCase的其他框架一起工作(比如Nose)。
这里有一个例子:
import unittest
import paramunittest
@paramunittest.parametrized(
('1', '2'),
#(4, 3), <---- Uncomment to have a failing test
('2', '3'),
(('4', ), {'b': '5'}),
((), {'a': 5, 'b': 6}),
{'a': 5, 'b': 6},
)
class TestBar(TestCase):
def setParameters(self, a, b):
self.a = a
self.b = b
def testLess(self):
self.assertLess(self.a, self.b)
除了使用setattr，我们还可以在Python 3.2及更高版本中使用load_tests。
class Test(unittest.TestCase):
pass
def _test(self, file_name):
open(file_name, 'r') as f:
self.assertEqual('test result',f.read())
def _generate_test(file_name):
def test(self):
_test(self, file_name)
return test
def _generate_tests():
for file in files:
file_name = os.path.splitext(os.path.basename(file))[0]
setattr(Test, 'test_%s' % file_name, _generate_test(file))
test_cases = (Test,)
def load_tests(loader, tests, pattern):
_generate_tests()
suite = TestSuite()
for test_class in test_cases:
tests = loader.loadTestsFromTestCase(test_class)
suite.addTests(tests)
return suite
if __name__ == '__main__':
_generate_tests()
unittest.main()
这可以使用元类优雅地解决:
import unittest
l = [["foo", "a", "a",], ["bar", "a", "b"], ["lee", "b", "b"]]
class TestSequenceMeta(type):
def __new__(mcs, name, bases, dict):
def gen_test(a, b):
def test(self):
self.assertEqual(a, b)
return test
for tname, a, b in l:
test_name = "test_%s" % tname
dict[test_name] = gen_test(a,b)
return type.__new__(mcs, name, bases, dict)
class TestSequence(unittest.TestCase):
__metaclass__ = TestSequenceMeta
if __name__ == '__main__':
unittest.main()
