Kinda wish Josh would mention how he structures his tests in his projects. Something I'm currently struggling at work is that within our code repos, the pattern that everyone seems to copy is mimic the src/ directory for the test/ directory, rather than co-locating tests along with components. This means a structure for components:

    src/
      components/
        Button/
          Button.tsx

Is just copied ad-hoc for tests, so we get this:

    test/
      components/
        Button/
          Button.test.tsx

Ideally it would be structured as so:

    src/
      components/
        Button/
          Button.tsx
          Button.test.tsx

This pattern makes it extremely taxing to utilize codemods in the future to transform repos into something else. It also, in my opinion, instills thinking that testing is separate from feature development and is often treated as such. As a result, my org often forgoes proper testing or tacking it on at the very end to just fulfill the motions of the dev cycle.

The oddest part is that some staff and principle engineers are very adamant about this structure. It's just additional boilerplate that doesn't help and makes it hard to understand what components have tests (especially when you get in the weeds of not having a flat component directory, where child components have nested directories often several layers deep). I have no idea where this pattern permeates but it should be discouraged in most frontend projects.

Co-location of files should absolutely be encouraged, the alternative is just a jumble of directories that make it hard to grok what is actually happening.

IDK, just ranting now at this point.