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
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
其他回答
使用unittest(从3.4开始)
从Python 3.4开始，标准库unittest包具有subTest上下文管理器。
参见文档:
26.4.7. 使用子测试区分测试迭代 分测验
例子:
from unittest import TestCase
param_list = [('a', 'a'), ('a', 'b'), ('b', 'b')]
class TestDemonstrateSubtest(TestCase):
def test_works_as_expected(self):
for p1, p2 in param_list:
with self.subTest():
self.assertEqual(p1, p2)
你也可以给subTest()指定一个自定义消息和参数值:
with self.subTest(msg="Checking if p1 equals p2", p1=p1, p2=p2):
用鼻子
鼻测试框架支持这一点。
示例(下面的代码是包含测试的文件的全部内容):
param_list = [('a', 'a'), ('a', 'b'), ('b', 'b')]
def test_generator():
for params in param_list:
yield check_em, params[0], params[1]
def check_em(a, b):
assert a == b
nosetests命令输出信息如下:
> nosetests -v
testgen.test_generator('a', 'a') ... ok
testgen.test_generator('a', 'b') ... FAIL
testgen.test_generator('b', 'b') ... ok
======================================================================
FAIL: testgen.test_generator('a', 'b')
----------------------------------------------------------------------
Traceback (most recent call last):
File "/usr/lib/python2.5/site-packages/nose-0.10.1-py2.5.egg/nose/case.py", line 203, in runTest
self.test(*self.arg)
File "testgen.py", line 7, in check_em
assert a == b
AssertionError
----------------------------------------------------------------------
Ran 3 tests in 0.006s
FAILED (failures=1)
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)
基于元类的答案在Python 3中仍然有效，但必须使用元类参数，而不是__metaclass__属性，例如:
class ExampleTestCase(TestCase,metaclass=DocTestMeta):
pass
您将从尝试testscenario库中受益。
testscenes为python unittest风格的测试提供了干净的依赖注入。这可以用于接口测试(通过单个测试套件测试许多实现)或经典的依赖项注入(在测试代码本身的外部提供依赖项测试，允许在不同情况下轻松测试)。
这被称为“参数化”。
有几个工具支持这种方法。例如:
pytest的装饰 参数化
结果代码如下所示:
from parameterized import parameterized
class TestSequence(unittest.TestCase):
@parameterized.expand([
["foo", "a", "a",],
["bar", "a", "b"],
["lee", "b", "b"],
])
def test_sequence(self, name, a, b):
self.assertEqual(a,b)
这将生成测试:
test_sequence_0_foo (__main__.TestSequence) ... ok
test_sequence_1_bar (__main__.TestSequence) ... FAIL
test_sequence_2_lee (__main__.TestSequence) ... ok
======================================================================
FAIL: test_sequence_1_bar (__main__.TestSequence)
----------------------------------------------------------------------
Traceback (most recent call last):
File "/usr/local/lib/python2.7/site-packages/parameterized/parameterized.py", line 233, in <lambda>
standalone_func = lambda *a: func(*(a + p.args), **p.kwargs)
File "x.py", line 12, in test_sequence
self.assertEqual(a,b)
AssertionError: 'a' != 'b'
由于历史原因，我将保留大约2008年的原始答案):
我使用的方法是这样的:
import unittest
l = [["foo", "a", "a",], ["bar", "a", "b"], ["lee", "b", "b"]]
class TestSequense(unittest.TestCase):
pass
def test_generator(a, b):
def test(self):
self.assertEqual(a,b)
return test
if __name__ == '__main__':
for t in l:
test_name = 'test_%s' % t[0]
test = test_generator(t[1], t[2])
setattr(TestSequense, test_name, test)
unittest.main()
