DrupalCon Vienna session retro: Test all the things!

For the kind of large scale projects we work on, it's essential that automated testing is a priority and firmly embedded in our technical culture. Stability and maintainability of the code we're working on helps to build trusting relationships and happy technical teams. I have for a long time been engaged with the developments of automated testing in Drupal core and internally we've worked hard to adapt these processes into the projects we build and fill-in any blanks where required.

I was fortunate enough to be selected to share this at DrupalCon Vienna. Without further ado, I present, Test all the things! Get productive with automated testing in Drupal 8:

Our current testing ethos is based around using the same tools for core and contrib for our bespoke Drupal project builds. Doing so allows us to context-switch between our own client work and contributed project or core work. To make this work we've addressed a few gaps in what's available to us out of the box.

Current State of Testing

I had some great conversations after the session with developers who were just starting to explore automated testing in Drupal. While the tools at our disposal are powerful, there is still lots of Drupal-specific knowledge required to become productive. My hope is the session helped to fill in some of the blanks in this regard.

E2E Testing

Because all of the test cases in core are isolated and individually setup environments/installations, end-to-end testing is tricky without some additional work. One of the touch points in the session was based around skipping the traditional set-up processes and using the existing test classes against pre-provisioned environments. Doing so replicates production-like environments in a test suite, which helps to provide a high-level of confidence tests are asserting behaviors of the whole system. Bringing this into core as a native capability is being discussed on drupal.org and was touched on in the session.

JS Unit Testing

One thing Drupal core has yet to address is JavaScript unit testing. For complex front-ends, testing JS application code with a browser is can become clumsy and hard to maintain. One approach we've used to address this is Jest. This nicely compliments front-ends where individual JavaScript modules can be isolated and individually tested.

Summing up, attending DrupalCon Vienna, presenting the session and meeting the members of the broader community was a great experience. I'm hopeful my session was able to contribute to the outstanding quality of sessions and technical discussions.