feat: ignore *.{test,spec}.{js,ts} and similar files

[rChaoz]

Closes #13008, please see issue for more details

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[Rich-Harris]

preview: https://svelte-dev-git-preview-kit-13009-svelte.vercel.app/

this is an automated message

[dummdidumm]

I don't think we need extra config for this - which could also be abused to hide files from the router which it should otherwise not (like a backdoor to customize your routing scheme in weird ways). .test/.spec.{js.ts} will suffice

[rChaoz]

I don't agree with that. First, because you may have different/multiple extensions, or a combination. It's not rare to see:

• x.test.svelte.js / x.svelte.test.js
• other extensions like .stories, for example used with +page.stories.svelte
• separation between unit/int tests, for example x.test.js and x.int.test.js/x.int.js

Also, I don't believe something shouldn't be added just because there is a chance it can be misused.

[Rich-Harris]

which could also be abused to hide files from the router

Maybe that's a feature? Because that's what this is actually doing — testExtensions is a misnomer, given that it doesn't magically wire up your tests or whatever. It just hides stuff from the router.

So it could be something like this instead:

// svelte.config.js
export default {
  kit: {
    router: {
      ignore: /\.(test|spec|stories)\./
    }
  }
};

I think we'd probably only want to apply it to the basename, and it should error if a valid route file (i.e. +page.svelte etc) was ignored, so that people didn't abuse it.

Thoughts? Should the regex in that example be the default?

[svelte-docs-bot]

Preview: https://svelte-dev-git-preview-kit-13009-svelte.vercel.app/

[Rich-Harris]

We decided to go with a non-config approach, so closing this in favour of #16715 — thank you!