Python 中的 fixture 和 fixtures

1 Fixture 概念

Fixture是测试中的概念:

• Fixture 指的是测试中依赖的数据和条件等等
• Python的 unittest 库提供了对 fixture的一些支持
• 每个TestCase 应该在setUp中, 自己负责资源的创建, 例如

class MyTestCase(unittest.TestCase):

    def my_fixture_setup(self):
        pass

    def setUp(self):
        super(MyTestCase, self).setUp()
        self.my_fixture_setup()

• 每个TestCase 应该新建一个函数, 负责资源的销毁. 并把这个新的函数加入到TestCase的cleanup列表当中

class MyTestCase(unittest.TestCase):

    def my_fixture_cleanup(self):
        print("++++ my_cleanup")

    def setUp(self):
        super(MyTestCase, self).setUp()
        self.addCleanup(self.my_fixture_cleanup)

以下是完整的代码

from __future__ import print_function
import unittest

class MyTestCase(unittest.TestCase):

    def my_fixture_setup(self):
        pass

    def my_fixture_cleanup(self):
        print("++++ my_cleanup")

    def setUp(self):
        super(MyTestCase, self).setUp()
        self.my_fixture_setup()
        self.addCleanup(self.my_fixture_cleanup)

    def tearDown(self):
        super(MyTestCase, self).tearDown()
        print("++++ tearDown")

    def my_cleanup(self):
        print("++++ my_cleanup")

    def test_case_1(self):
        print("++++ test case 1")

2 Python 中的 Fixtures 包

Fixtures(复数)是Python中的一个包, 提供了一些工具包来快速创建/销毁 fixture

https://pypi.python.org/pypi/fixtures

• Test Case需要派生于 testtools.TestCase 类
• 如果需要自定义Fixtures, 需要派生于 fixtures.Fixture类, 并覆写父类的setUp/cleanUp方法

一个自定义Fixtures类的例子如下

from __future__ import print_function
import fixtures
import testtools

class MyFixture(fixtures.Fixture):
    def setUp(self):
        super(MyFixture,self).setUp()
        self.frobnozzle = 42
        print("++++ MyFixture.setup()")

    def cleanUp(self):
        super(MyFixture,self).cleanUp()
        print("++++ MyFixture.cleanup()")
        print()

class MyTestCase(testtools.TestCase):

    def setUp(self):
        super(MyTestCase, self).setUp()
        self.my_fixture = self.useFixture(MyFixture())
        print("++++ setUp")

    def tearDown(self):
        super(MyTestCase, self).tearDown()
        print("++++ tearDown")

    def test_case_1(self):
        self.assertEqual(42, self.my_fixture.frobnozzle)
        print("++++ test case 1")