vite-browserhash-repro
This repo demonstrates an issue affecting SvelteKit: sveltejs/kit#5952
Background
When SvelteKit server-renders a page, it includes a <script> tag that is effectively this:
<script type="module">
import { start } from '/node_modules/@sveltejs/kit/src/runtime/client/start.js';
// ...
</script>This module, which is inside the @sveltejs/kit package but not exposed via pkg.exports, imports a module that is exposed via pkg.exports:
import { error } from '../../index/index.js';If user code imports the same module...
import { error } from '@sveltejs/kit';...then ideally it would resolve to the same module. Instead, the latter import gets a ?v=${browserHash} suffix:
/node_modules/@sveltejs/kit/src/runtime/index/index.js
/node_modules/@sveltejs/kit/src/runtime/index/index.js?v=xyz123
Because of that, the module is initialised twice, and instanceof checks fail.
Reproduction
This repro demonstrates the same thing happening in a much simpler form. After installing dependencies, run npm run dev and visit localhost:5173. The expectation is that the test module will be instantiated once, but it's instantiated twice — once from index.html...
<script type="module" src="/node_modules/test/index.js"></script>...and once from src/index.js:
import 'test';