64 lines
2.2 KiB
Markdown
64 lines
2.2 KiB
Markdown
# Chapter 2. Extending Our Functional Test Using the unittest Module
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We are trying to build to-do list Django web app
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## 2.1 Using a FT to Scope Out a Minimum Viable App
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* **Functional Tests** = tests that let us see how the app *functions* from user's perspective
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* It's like a specification for app
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* Tends to track *User Story*
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* **Functional Test** == **Acceptance Test** == **End-to-End Test**
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Steps to create a FT for a MVP/A (Minimum Viable Product/App):
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1. Prepare a User Story (e.g. user story for to-do list)
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2. Add test assertions along user story, which is *expected fail*
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## 2.2 Python Standard Library's unittest Module
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python's default `assert` isn't helpful.
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> The assert keyword is used when debugging code.
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> The assert keyword lets you test if a condition in your code returns True, if not, the program will raise an AssertionError.
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`unittest` module of python standard library can be used
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Following are highlights of code snippet shown below:
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* tests can be organized into classes, which inherit from `unittest.TestCase`
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* `setUp` and `tearDown` are special methods that will be run before/after each test, even test failed
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* main body of tests is in `test_can_start_a_list_and_retrieve_it_later`.
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* **Any method whose name starts with test is a test method, and will be run by test runner**
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* Can have more than one test methods per class.
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* Use `self.assertIn()` instead of `assert`. More helper functions like `assertEqual`, `assertTrue`, and `assertFalse` are available in *unittest*
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* `warning='ignore'` suppresses a superfluous `ResourceWarning`.
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```python
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class NewVisitorTest(unittest.TestCase):
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def setUp(self):
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self.browser = webdriver.Firefox()
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def tearDown(self):
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self.browser.quit()
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def test_can_start_a_list_and_retrieve_it_later(self):
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...
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if __name__ == '__main__':
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unittest.main(warnings='ignore')
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```
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Hence, a full cycle of test can be executed as it
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1. Open Firefox
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2. Test title
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3. Close Firefox
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4. Return test result
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## Useful TDD Concepts in this chapter
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* **User Story**: A description of how the application will work from the point of view of the user. Used to structure a functional test.
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* **Expected Failure**: When a test fails in the way that we expected it to. |