如何將mock.patch移到setUp？

Question

我有以下兩個單元測試：

    @mock.patch('news.resources.generator.Generator.get_header')
    @mock.patch('news.scraper.bbc_spider.BBCSpider.save_scraped_rss_into_news_model')
    @mock.patch('news.scraper.bbc_spider.BBCSpider.get_news_urls')
    @mock.patch('requests.get')
    def test_get_header_is_called(self, req_get, spi_news, spi_save_rss, get_head):
        spi_news.return_value = {'x': 1}
        gen = Generator()
        gen.get()
        get_head.assert_called_with()

    @mock.patch('news.resources.generator.Generator.get_header')
    @mock.patch('news.scraper.bbc_spider.BBCSpider.save_scraped_rss_into_news_model')
    @mock.patch('news.scraper.bbc_spider.BBCSpider.get_news_urls')
    @mock.patch('requests.get')
    def test_task_url_is_save_scraped_rss_into_news_model(self, req_get, spi_news, spi_save_rss, get_head):
        spi_news.return_value = {'x': 1}
        gen = Generator()
        gen.get()
        tasks = self.taskqueue_stub.GetTasks("newstasks")
        self.assertEqual(tasks[0]['url'], '/v1/worker/save-scraped-rss-into-news-model')

如您所見，有很多代碼重復。 有沒有一種方法可以將模擬文件.patch移到setUp（）？

Class TestGenerator(TestBase):
    def setUp(self):
        super(TestGenerator, self).setUp()
        mock.patch() ???

    def test_get_header_is_called(self, req_get, spi_news, spi_save_rss, get_head):
            spi_news.return_value = {'x': 1}
            gen = Generator()
            gen.get()
            get_head.assert_called_with()

    def test_task_url_is_save_scraped_rss_into_news_model(self, req_get, spi_news, spi_save_rss, get_head):
            spi_news.return_value = {'x': 1}
            gen = Generator()
            gen.get()
            tasks = self.taskqueue_stub.GetTasks("newstasks")
            self.assertEqual(tasks[0]['url'], '/v1/worker/save-scraped-rss-into-news-model')

Answer 1

您在這里有2個選項-首先，您可以將補丁移至該類：

@mock.patch('news.resources.generator.Generator.get_header')
@mock.patch('news.scraper.bbc_spider.BBCSpider.save_scraped_rss_into_news_model')
@mock.patch('news.scraper.bbc_spider.BBCSpider.get_news_urls')
@mock.patch('requests.get')
class TestGenerator(TestBase):
    def test_get_header_is_called(self, req_get, spi_news, spi_save_rss, get_head):
      pass

當您在類的mock.patch家族中使用某些東西時，它的行為就像您分別修補了以“ test” ¹開頭的每個方法一樣。

您的另一個選擇是在安裝程序中啟動修補程序。 在一個虛構的示例中（保存輸入），它看起來像這樣：

class SomeTest(TestCase):
    def setUp(self):
        super(SomeTest, self).setUp()
        patch = mock.patch('foo.bar.baz')
        mock_baz = patch.start()  # may want to keep a reference to this if you need to do per-test configuration
        self.addCleanup(patch.stop)

addCleanup是在python2.7中添加的（太棒了！）。 如果您不需要較舊的python2.x版本，則應使用它，因為它比其他版本更健壯。 最簡單的選擇是僅停止tearDown中的所有修補程序：

class SomeTest(TestCase):
    def setUp(self):
        super(SomeTest, self).setUp()
        patch = mock.patch('foo.bar.baz')
        mock_baz = patch.start()  # may want to keep a reference to this if you need to do per-test configuration

    def tearDown(self):
        super(SomeTest, self).tearDown()
        mock.patch.stopall()

但您也可以保留對各個修補程序的引用self.patch1 = mock.patch(...) ，然后根據需要在tearDown單獨停止該修補程序。

^{1實際上， mock.TEST_PREFIX默認為"test"}