Component testing Vue with Pinia: "no active Pinia" error only on Github actions

[hackel]

I have a problem running my test suite on Github actions (using cypress-io/github-action@v6). A handful of tests always come back with the error:
"getActivePinia()" was called but there was no active Pinia. Are you trying to use a store before calling "app.use(pinia)"?
This does not happen when I run the tests locally—everything passes. I have tried different solutions and even switched away from createTestingPinia and configure it as described here: https://cypress-testing-handbook.netlify.app/pinia.html#configuring-cypress-and-pinia but still the errors persist.

Has anyone else experienced this issue, or do you have an idea what might be causing it?

Edit: A clue! By deleting the Vite cache in node_modules/.vite, I start getting errors locally. This included the getActivePinia error mentioned above, but also the dreaded Failed to fetch dynamically imported module: component.js that is still occasionally a problem for others as well. Interestingly, I seem to be getting these errors on the same set of files as I am getting in Github actions, which makes sense since the Vite cache is not copied between runs.

[hackel]

In case anyone stumbles across this post, here is the solution (or work-around) that I found.

I noticed that before each error, I was seeing messages from Vite like:

4:29:29 PM [vite] (client) ✨ new dependencies optimized: bootstrap-vue-next/components/BFormFile
4:29:29 PM [vite] (client) ✨ optimized dependencies changed. reloading

So I added all of these bootstrap-vue-next dependencies to the optimizeDeps section of my vite.config.js file, and like magic, the tests started passing. I had to take a couple of passes at this, but so far it's been reliable. My working theory is that when Vite reloads, the contents of component.js don't get run again, thus resulting in the 'no active pinia' error.