Sourcemaps are broken in 0.8.0 (works fine in 0.7.2) when using with Vue SFC options api.

[leo-buneev]

if you have Vue SFC, and use options Api, and somewhere in <script> section use identifier that should be auto-imported, source maps will break.

Repro: https://stackblitz.com/edit/vite-zrayd3?file=src/App.vue
Click the button and look at reported line in browser console.

This worked before transition to unimport - i.e. in 0.7.2

[asmodai1985]

I had the same trouble.It is resolved in 0.8.7. but there are still problems when debug,

[luqiudi]

i had the same trouble in tsx files.
it broken sourcemap

[leo-buneev]

Actually found the issue! Seems to be simple.

on 0.7.2 it worked, because there was "sourcemap:" option in config that defaulted to false. And actually, you don't really need sourcemaps with this plugin, because it puts all injected imports into single line.

on 0.8.0 onwards, there is no "sourcemap" option, and plugin always generates sourcemaps with magic-string library. However, generated sourcemaps in my case are totally wrong, and to fix that it was enough to pass hires: true option to s.generateMap(). This way sourcemap is generated correctly.

(I don't think issue is in magic-string library - rather, somewhere in vite's sourcemaps merging logic)

BTW, exactly same problem was found in unplugin-vue-components.
Should I create a MR to add hires: true, or to add sourcemap: true|false back to config @antfu ?

---

UPD: After further investigation, hires: true can significantly increase memory and cpu usage during build of huge projects.

So, I'm proposing following fix:

1. Add sourcemap: false | true | 'hires' option to plugin config (defaults to "false" or "true", up to @antfu) (for both unplugin-auto-import and unplugin-vue-components)
2. change unplugin-vue-components transformer so it doesn't add newlines - this way even without sourcemaps debugging in dev mode will work

I can create PR if you agree

[zam157]

@leo-buneev I had the same problem. Maybe antfu didn't notice this issue, you should PR directly

[superchangme]

I had the same problem,even i upgrade vite to 4.0 ,unplugin-auto-import unplugin-vue-components to newleast version debugger code position is still wrong:(

[whaaaley]

Yup, broken in both auto-import and components. How do people live without sourcemaps? They tell you exactly where the problem is... I'll probably have to migrate away from both of these plugins, unfortunately.

[whaaaley]

@leo-buneev Did you ever manage to resolve this issue? I see some things were merged since but the issue still persists for me.

[leo-buneev]

I've fixed it for my project in a fork. It's not kept up-to-date, though.

https://github.com/leo-buneev/unplugin-auto-import.git
https://github.com/leo-buneev/unplugin-vue-components.git

In the end my solution was to not generate sourcemaps from plugin whatsoever. It's (obviously) fastest, and the only downside - transformed code shouldn't add new lines.

unplugin-auto-import didn't need any fix (besides disabling sourcemaps - see fork) - it doesn't generate new lines.
unplugin-vue-components was changed to not generate newlines.