WTM21 - Unit Tests 101 by Ana Carolina Riekstin and Myriam Moar

What are unit tests, what is the purpose of writing, the benefits (and costs), how to write them? If you are looking for a place to start your unit tests journey, or build the courage to finally attack that refactoring you have been postponing, look no further!

Ana Carolina Riekstin
Montreal, Qc, Canada / Bell
Software Developer
Ana Carolina is a Brazilian based in Montreal who has been around research and development related to computer networks and network management, smart homes and cities, and sustainability. Currently a Software Developer at Bell, holds a PhD in computer engineering. Loves to talk, specially about her dog, Caco, and Brazilian cheese bread recipes. Still searching for the answer to life, the universe and everything.

Myriam Moar
Lévis, Québec / Elapse Technologies
Software Developer at Elapse Technologies
Myriam Moar works as a software developer and resident in the mentoring and improvement program at Elapse Technologies. This program aims to train future teachers and coaches in the field of software engineering. Motivated by learning new knowledge, whether technical or human, Myriam is always pushing her involvement in the field. Committed to continuous improvement, she is particularly involved as a teaching assistant at Université Laval, where she addresses quality and tests, but also the challenges of team collaboration in software engineering. After all, people are at the center of all collaborative work. Her everyday approach tends to focus on the importance and contribution of individuals within a team.

Transcript

1. Unit Tests 101 UT python mocks </> Ana Carolina Riekstin Myriam MOAR
2. “Tests are stories we tell the next generation of programmers on a project” —Roy Osherove
3. Why? ↑ good practices, doc, refactoring... 02 How to Test conventions, mocks, helpers, setups TABLE OF CONTENTS What? What is a unit, classification 01 What to Test Contracts and behaviors 04 03 Conclusion TDD, BDD, other languages, refs Demo Time python > pytest, fixtures, mocks 06 05
4. What is UNIT TEST What is a unit, scope, classification 01.
5. A unit is the smallest testable part of any software
6. TEST PYRAMID MARS SMALL 70% More isolation More integration MEDIUM 20% LARGE 10% e2E Tests Slower $$$ Faster $ Integration Tests UNIT Tests
7. Other shapes MARS More isolation More integration e2E Tests Slower Faster Integration Tests UNIT Tests The Ice Cream Cone The Hourglass
8. Guides Development Critiques the product Business Technology Unit Test Functional Tests Load Testing UAT (User Acceptance Testing) Performance Testing Security Testing Scenarios Exploratory Testing Component Tests UX Testing Simulations Q2 Q3 Q1 Q4 Testing quadrant
9. WHY UNIT TEST ↑ good practices, documentation, refactoring... 02.
10. The Process is more than just “tests” CLEANER CODE Hints on how to improve the code ... BETTER ARCHITECTURE … and the architecture EXPLORATION Explore your codebase → learn Documentation Good tests will tell you a story > reqs. FAST RETROACTION Very quick feedback; sooner → cheaper Refactoring Reduces the risks
11. What to TEST Contracts and behaviors 03.
13. Example of What to/NOT TO Test https://www.w3schools.com/java
14. HOW TO UNIT TEST Conventions, mocks, fragility... 04.
15. GIVEN-WHEN-THEN Use a naming convention to easily identify your test case Conventions AND TIPS refactoring Unit tests are part of the code, they deserve it too Test only one thing Your test should have only one reason to fail USE MEANINGFUL NAMES Your test should read like a story
16. Mocks - isolation
17. Mocks - PIlot
18. Mocks - verify
19. IT’s DEMO TIME 05.
20. Demo with Pytest PYTEST • parametrize • raises Assertions • assert • grappa > should Mocking • unittest.mock > Mock > return_value • patch > side_effect • monkeypatch
21. Conclusion 06.
22. Examples in Other Languages https://www.webucator.com/how-to/how-write-unit-test-java.cfm
23. Some References Unit tests • Working effectively with legacy code, a book by Michael C. Feathers • https://martinfowler.com/bliki/UnitTest.html • Test or not to test, that is the question: https://medium.com/@tasdikrahman/what-should-and-s hould-not-be-tested-in-unit-tests-7e6bdeb744e4 • You Still Don’t Know How to Do Unit Testing (and Your Secret is Safe with Me): https://stackify.com/unit-testing-basics-best-practices/ TDD • https://devqa.io/pros-cons-test-driven-development/ JAVA • https://www.toptal.com/java/unit-integration-junit-tests Growing Object-Oriented Software, a book by Steve Freeman and Nat Pryce C# • https://stackify.com/unit-testing-basics-best-practices/ Python • https://www.oreilly.com/library/view/python-testing-with /9781680502848/ Python Test With pytest, a book by Brian Okken • Pytest: https://docs.pytest.org/en/stable/contents.html • More: https://realpython.com/python-testing, • Unittest: https://docs.python.org/3/library/unittest.html • Mocking: https://www.toptal.com/python/an-introduction-to-mock ing-in-python • Mocking, Monkey Patching... https://codefellows.github.io/sea-python-401d7/lectures/ mock.html • Mock, another "tool": https://medium.com/ryans-dev-notes/python-mock-and -magicmock-b3295c2cc7eb Go • https://golang.org/pkg/testing • https://medium.com/rungo/unit-testing-made-easy-in-g o-25077669318
24. To continue your exploration... ATDD BDD INtegration tests TDD
25. CREDITS: This presentation template was created by Slidesgo, including icons by Flaticon, infographics & images by Freepik THANKS! Do you have any questions? ana.ca.r@gmail.com myriam.moar@elapsetech.com
26. THE END