fix: avoid missing source warnings for react-refresh

[nwidynski]

Description

This PR marks /@react-refresh as a virtual module to avoid false positive "missing source" warnings.

[sapphi-red]

Could you provide a reproduction when this is needed?

[nwidynski]

@sapphi-red Do you happen to have a default sandbox template I can use for reproduction?

[sapphi-red]

@nwidynski You can use http://vite.new/react-ts

[nwidynski]

@sapphi-red https://stackblitz.com/edit/vitest-tests-browser-examples-7wxz6en1

This one works, although you need to download and execute it locally. Stackblitz has troubles spawning a headless browser. Just run vitest and you will see the warning pop up.

[sapphi-red]

OK. I understand the root cause. The ideal fix is to inject the source at

vite/packages/vite/src/node/server/pluginContainer.ts

Line 943 in a50b21b

_getCombinedSourcemap(): SourceMap | { mappings: '' } | null {

when inputMap does not exist. injectSourcesContent should not be needed if that's done.

[nwidynski]

@sapphi-red Like this?

if (sm.sources.length === 1 && !sm.sources[0] || !this.originalSourcemap) {
  combinedMap = {
    ...sm,
    sources: [this.filename],
    sourcesContent: [this.originalCode],
  }
}

[sapphi-red]

I think something like that. I haven't checked why that part is not running though.

[ArnaudBarre]

This is a bug in the SWC plugin, fixed in vitejs/vite-plugin-react#478