Testing React Applications Like an Engineer

Austin Shelby emphasizes the importance of testing as a proactive rather than an afterthought approach. He advocates for testing to be focused on user flows and documenting application functionality clearly and comprehensively.

NASA thoroughly tests every function and line of code of the rover by replicating Mars-like conditions on Earth, including similar soil, extreme temperatures, sounds, and winds.

Austin Shelby believes that in the age of Next.js, the traditional testing pyramid is less relevant. He suggests focusing on user-centric testing rather than strictly adhering to unit, integration, and end-to-end test ratios.

The 'arrange, act, assert' pattern is a structure for writing clear and effective tests. It involves setting up the test conditions (arrange), performing the test actions (act), and verifying the results (assert).

Austin Shelby supports TDD as a tool for solving complex problems. He recommends reproducing bugs locally, fixing them, and using tests as safeguards for confident deployment.

He provides an example of registering a new user in a notes app, demonstrating how to write a simple test using Playwright that verifies successful registration and redirection to the homepage.

User stories help create clear and relatable test cases that communicate the intent of the application’s functionality in a language understandable by both technical and product teams.

Tests serve as documentation by clearly outlining the expected behaviors and functions of the application. If functionality changes, failing tests highlight where issues occur.

Behavior-Driven Development (BDD) encourages using a shared language for writing test scenarios, enabling better communication between technical and product individuals about application functions.

Austin Shelby finds some BDD tools like Cucumber to be gimmicky and suggests focusing on the specificity and clarity of test scenarios instead.