接口自动化参数化（二）

parameterized参数详解（转载）

# test_math.py
from nose.tools import assert_equal
from parameterized import parameterized

import unittest
import math

@parameterized([
    (2, 2, 4),
    (2, 3, 8),
    (1, 9, 1),
    (0, 9, 0),
])
def test_pow(base, exponent, expected):
    assert_equal(math.pow(base, exponent), expected)

class TestMathUnitTest(unittest.TestCase):
    @parameterized.expand([
        ("negative", -1.5, -2.0),
        ("integer", 1, 1.0),
        ("large fraction", 1.6, 1),
    ])
    def test_floor(self, name, input, expected):
        assert_equal(math.floor(input), expected)

在 nose (and nose2)下运行:

$ nosetests -v test_math.py
test_math.test_pow(2, 2, 4) ... ok
test_math.test_pow(2, 3, 8) ... ok
test_math.test_pow(1, 9, 1) ... ok
test_math.test_pow(0, 9, 0) ... ok
test_floor_0_negative (test_math.TestMathUnitTest) ... ok
test_floor_1_integer (test_math.TestMathUnitTest) ... ok
test_floor_2_large_fraction (test_math.TestMathUnitTest) ... ok

----------------------------------------------------------------------
Ran 7 tests in 0.002s

OK
As the package name suggests, nose is best supported and will be used for all further examples.

With py.test (version 2.0 and above):

$ py.test -v test_math.py
============================== test session starts ==============================
platform darwin -- Python 2.7.2 -- py-1.4.30 -- pytest-2.7.1
collected 7 items

test_math.py::test_pow::[0] PASSED
test_math.py::test_pow::[1] PASSED
test_math.py::test_pow::[2] PASSED
test_math.py::test_pow::[3] PASSED
test_math.py::TestMathUnitTest::test_floor_0_negative
test_math.py::TestMathUnitTest::test_floor_1_integer
test_math.py::TestMathUnitTest::test_floor_2_large_fraction

=========================== 7 passed in 0.10 seconds ============================
With unittest (and unittest2):

$ python -m unittest -v test_math
test_floor_0_negative (test_math.TestMathUnitTest) ... ok
test_floor_1_integer (test_math.TestMathUnitTest) ... ok
test_floor_2_large_fraction (test_math.TestMathUnitTest) ... ok

----------------------------------------------------------------------
Ran 3 tests in 0.000s

OK
(note: because unittest does not support test decorators, only tests created with @parameterized.expand will be executed)

在@parameterized与@parameterized.expand装饰接受列表或可迭代的元组或param(...)，或调用它返回一个列表或可迭代, 下面是比较全的使用方法示例：

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from parameterized import parameterized, param

# A list of tuples
@parameterized([
    (2, 3, 5),
    (3, 5, 8),
])
def test_add(a, b, expected):
    assert_equal(a + b, expected)

# A list of params
@parameterized([
    param("10", 10),
    param("10", 16, base=16),
])
def test_int(str_val, expected, base=10):
    assert_equal(int(str_val, base=base), expected)

# An iterable of params
@parameterized(
    param.explicit(*json.loads(line))
    for line in open("testcases.jsons")
)
def test_from_json_file(...):
    ...

# A callable which returns a list of tuples
def load_test_cases():
    return [
        ("test1", ),
        ("test2", ),
    ]
@parameterized(load_test_cases)
def test_from_function(name):
    ...

请注意，在使用迭代器或生成器时，在开始测试运行之前，所有项目都将被加载到内存中（我们明确地做到这一点，以确保生成器在多进程或多线程测试环境中精确地耗尽一次） 。

@parameterized装饰可用于测试类的方法，和独立的功能：

from parameterized import parameterized

class AddTest(object):
    @parameterized([
        (2, 3, 5),
    ])
    def test_add(self, a, b, expected):
        assert_equal(a + b, expected)

@parameterized([
    (2, 3, 5),
])
def test_add(a, b, expected):
    assert_equal(a + b, expected)

并且@parameterized.expand可以用于在不能使用测试生成器的情况下生成测试方法（例如，当测试类是子类时unittest.TestCase）：

import unittest
from parameterized import parameterized

class AddTestCase(unittest.TestCase):
    @parameterized.expand([
        ("2 and 3", 2, 3, 5),
        ("3 and 5", 2, 3, 5),
    ])
    def test_add(self, _, a, b, expected):
        assert_equal(a + b, expected)

会创建测试用例：

$ nosetests example.py
test_add_0_2_and_3 (example.AddTestCase) ... ok
test_add_1_3_and_5 (example.AddTestCase) ... ok

----------------------------------------------------------------------
Ran 2 tests in 0.001s

OK

请注意，@parameterized.expand通过在测试类上创建新方法。如果第一个参数是一个字符串，该字符串将被添加到方法名称的末尾。例如，上面的测试用例会生成方法 test_add_0_2_and_3和test_add_1_3_and_5。

生成的测试用例的名称@parameterized.expand可以使用testcase_func_namekeyword参数自定义。该值应该是这三个参数的函数：testcase_func，param_num，和params，应该返回测试用例的名字。 testcase_func将被测试的功能，param_num将参数列表中的测试用例参数的索引，和param （一个实例param）将被使用的参数。

import unittest
from parameterized import parameterized

def custom_name_func(testcase_func, param_num, param):
    return "%s_%s" %(
        testcase_func.__name__,
        parameterized.to_safe_name("_".join(str(x) for x in param.args)),
    )

class AddTestCase(unittest.TestCase):
    @parameterized.expand([
        (2, 3, 5),
        (2, 3, 5),
    ], testcase_func_name=custom_name_func)
    def test_add(self, a, b, expected):
        assert_equal(a + b, expected)

创建测试用例：

$ nosetests example.py
test_add_1_2_3 (example.AddTestCase) ... ok
test_add_2_3_5 (example.AddTestCase) ... ok

----------------------------------------------------------------------
Ran 2 tests in 0.001s

OK

该param(...)助手类存储一个特定的测试情况的参数。它可以用于将关键字参数传递给测试用例：

from parameterized import parameterized, param

@parameterized([
    param("10", 10),
    param("10", 16, base=16),
])
def test_int(str_val, expected, base=10):
    assert_equal(int(str_val, base=base), expected)

如果测试用例有一个docstring，则该测试用例的参数将追加到docstring的第一行。这个行为可以用doc_func参数控制：

from parameterized import parameterized

@parameterized([
    (1, 2, 3),
    (4, 5, 9),
])
def test_add(a, b, expected):
    """ Test addition. """
    assert_equal(a + b, expected)

def my_doc_func(func, num, param):
    return "%s: %s with %s" %(num, func.__name__, param)

@parameterized([
    (5, 4, 1),
    (9, 6, 3),
], doc_func=my_doc_func)
def test_subtraction(a, b, expected):
    assert_equal(a - b, expected)

$ nosetests example.py
Test addition. [with a=1, b=2, expected=3] ... ok
Test addition. [with a=4, b=5, expected=9] ... ok
0: test_subtraction with param(*(5, 4, 1)) ... ok
1: test_subtraction with param(*(9, 6, 3)) ... ok

----------------------------------------------------------------------
Ran 4 tests in 0.001s

OK

原版博客链接:

http://www.cnblogs.com/itstu/p/6955296.html

(只为了自己看的时候方便进行转载)