Episode 60: Testing in Context with Lachlan Miller (Part 1)

Enjoy the Vue

Today’s special guest on Enjoy the Vue is Lachlan Miller, a full-stack software developer who is passionate about open-source, test-driven development, and mentoring. You may know him for his involvement in the Vue.js community and his work on Vue Test Utils. You may have even read the book he wrote about it, Design Patterns for Vue.js, which arms developers with the tools, patterns, and concepts they need to build complex, scalable, and testable applications. In part one of our conversation with Lachlan, we cover testing in all its complexity, from viewing it as everyone’s responsibility, not just the developer’s, to deciding on which tests to use, deciding where your priorities lie, and how you can put in 20 percent effort for 80 percent output. Tune in today!

Key Points From This Episode:

  • An introduction to today’s special guest, Lachlan Miller.
  • Given the hypothetical opportunity to test only one thing about an app, Ben, Tessa, and Lachlan weigh in.
  • Lachlan suggests doing a screenshot test of the application using a tool like Percy.
  • Hear about the distinction between screenshot tests and snapshot tests.
  • The panel reflects on whether developers should test their own code or have a QA team assume that responsibility.
  • The spectrum of testing, from end-to-end to the more fine-grained and individual unit tests.
  • Learn about Testing Library Vue, a recently popular alternative to a library like Cypress.
  • The benefits of having accessibility testing built in, for both developers and users.
  • How to decide where your priorities lie based on which tests you focus on.
  • Lachlan explains how he uses unit tests to drive development while end-to-end tests function more like a quality tool.
  • How you can use the Pareto effect to make these decisions as a developer: how can you put in 20 percent effort for 80 percent output?
  • Some of the panel’s favorite resources and methodologies for writing Vuex tests.


  • “If we think of testing as not just the developer's responsibility but everyone’s responsibility, it's about quality assurance and confidence. Everyone in the organization wants to be involved in the quality of their product, which is why visual tests can be very useful.” — @Lachlan19900 [0:05:31]
  • “If you are interested in the more end-to-end tests but you don't want to spin up a full browser, I would definitely recommend checking out Testing Library Vue, which is running on top of Vue Test Utils.” — @Lachlan19900 [0:15:45]
  • “The most important thing is you are confident in your app. Everyone's going to have a different version of confidence, but if you have a feature and if it breaks and it would cause a bad thing to happen to your business, you probably want to have a test around that.” — @Lachlan19900 [0:19:56]
  • “A good rule of thumb is the more you can test your application or your apps in a production-like manner, it's going to be better.” — @Lachlan19900 [0:30:36]

Resources mentioned:

Special Guest: Lachlan Miller.

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