Should you always start testing your code with unit tests? When does it make sense to look at integration or end-to-end testing as a first step instead? This week on the show, we speak with previous guest Eric Matthes about where to begin testing your code.

Eric is the author of the popular book Python Crash Course. Early in the development of the book, he decided to introduce testing and added a chapter on testing code with pytest.

Over the past couple of years, Eric has continued to consider when and where to test a project’s code. He thinks there are hazards to always starting with unit tests. The type of project and its audience should determine what kind of testing to employ initially.

We discuss using pytest to develop integration tests on multiple types of projects. We also explore fixtures and what goes into building a test suite. Eric also shares criteria for when and where it makes sense to add unit tests to a project.

Course Spotlight: Using Python’s assert to Debug and Test Your Code

In this course, you’ll learn how to use Python’s assert statement to document, debug, and test code in development. You’ll learn how assertions might be disabled in production code, so you shouldn’t use them to validate data. You’ll also learn about a few common pitfalls of assertions in Python.

Topics:

00:00:00 – Introduction
00:01:47 – Submitting talks to conferences
00:04:10 – Don’t start with unit tests!
00:07:35 – How did you start with testing?
00:11:30 – Example of a project needing tests
00:14:54 – Defining types of tests
00:16:44 – Integration vs end-to-end tests
00:19:09 – When should you build tests?
00:22:13 – Trade offs of integration vs unit tests
00:24:05 – Why is there push back on this idea?
00:27:36 – Video Course Spotlight
00:29:09 – Using pytest
00:33:24 – Transcripts project example
00:37:03 – py-image-border project
00:40:29 – Criteria for when you should write unit tests
00:48:51 – How to practice writing tests
00:50:28 – Building an integration test and pytest fixtures
00:55:05 – What’s in the test folder?
00:56:31 – Idea for a PyCon tutorial on implementing tests
00:57:29 – Other pytest advice and parametrization
01:01:13 – Caveats to not starting with unit tests
01:02:30 – pytest documentation and other advice
01:05:23 – How to reach Eric online
01:06:47 – What are you excited about in the world of Python?
01:08:23 – What do you want to learn next?
01:09:48 – What conferences are you attending?
01:10:06 – Thanks and goodbye

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