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Description

Something like this doesn't work properly in tsdown currently:

  plugins: [
    {
      name: 'externalize-shared',
      async resolveId(id, importer) {
        const resolved = await this.resolve(id, importer)
        if (resolved?.id.includes('shared')) {
          return { id: resolved.id, external: 'relative' }
        }
      }
    }
  ]

It works for the JS part, like if src/foo/bar.ts has import {} from '../../shared', then the compiled dist/foo/index.js has ../shared.js, but the DTS part is left with ../../shared.

(I know this example is simple enough to be specified via external/deps.neverBundle, but the real use case has less simple logic.)

Earlier code kept the id unchanged for dts files since it returned it's own external object instead of respecting other resolveId hooks in the chain.

Linked Issues

Additional context