Vite Library Mode Build Different between Windows and Linux - node-modules

Question

This is a crosspost from my github discussion, but I wanted to see if anyone has any thoughts here.
I'm using vite for an npm package that's in "library mode." I have 2 files:
utilities.ts
export function thisGetsRemovedInBundle() {
console.log('This should be in the bundle!');
}
export function thisIsUsed() {
console.log('Used!');
return 1;
}
components/index.ts
import { thisIsUsed } from '../utilities';
export default {
Hello: thisIsUsed(),
};
vite.config.ts
import { defineConfig } from 'vite';
import vue from '#vitejs/plugin-vue';
export default defineConfig({
plugins: [vue()],
build: {
lib: {
entry: 'components/index.ts',
formats: ['es'],
},
rollupOptions: {
external: ['vue'],
input: {
index: 'components/index.ts',
utilities: 'utilities.ts',
},
output: {
dir: 'dist',
format: 'es',
entryFileNames: '[name].js',
},
},
},
});
When I build this on a Windows 10 machine, it produces the following in index.js:
function thisIsUsed() {
console.log("Used!");
return 1;
}
var index = {
Hello: thisIsUsed()
};
export { index as default };
On Ubuntu, it produces this:
import { thisIsUsed } from "./utilities.js";
var index = {
Hello: thisIsUsed()
};
export { index as default };
Notice in the Windows build, it doesn't import the function but rather adds it as if it's part of index.js. I would expect it to be like the latter because in the Windows bundle, it has duplicated code (both files have a copy of thisIsUsed).
Is there some fundamental npm or node magic that I'm missing between these builds? If so, how do I solve this issue so my build always looks like the Ubuntu build (without having to use a Linux machine or Unix shell).

Answer 1

I ended up reporting a bug here, and while it appears valid, it can be fixed easily by using path.resolve and __dirname when defining the path to the input files. e.g. in the vite.config.ts above, it should be:
import { defineConfig } from 'vite';
import vue from '#vitejs/plugin-vue';
import path from 'path';
export default defineConfig({
plugins: [vue()],
build: {
lib: {
entry: 'components/index.ts',
formats: ['es'],
},
rollupOptions: {
external: ['vue'],
input: {
index: path.resolve(__dirname, 'components/index.ts'),
utilities: path.resolve(__dirname, 'utilities.ts'),
},
output: {
dir: 'dist',
format: 'es',
entryFileNames: '[name].js',
},
},
},
});