unplugin-dts

In a monorepo, if Package A depends on an unpublished Package B, the generated .d.ts files for Package A might still contain import { ... } from 'packageB', which will fail for consumers.

Method 1: Process source code directly (Recommended)

Configure the plugin to process the source code of the internal package instead of its build output. This ensures TypeScript treats the types as part of Package A.

vite.config.ts:

import { defineConfig } from 'vite'
import dts from 'vite-plugin-dts'
import { resolve } from 'node:path'

export default defineConfig({
  resolve: {
    alias: {
      // Point to the source entry of the internal package
      'packageB': resolve(__dirname, '../packageB/src/index.ts'),
    },
  },
  plugins: [
    dts({
      // Include the internal package's source files so they are emitted together
      include: ['src', '../packageB/src'],
      tsconfigPath: resolve(__dirname, 'tsconfig.app.json'),
    }),
  ],
})

tsconfig.app.json:

{
  "compilerOptions": {
    "paths": {
      "packageB": ["../packageB/src/index.ts"]
    }
  }
}

Note: Ensure the internal package's package.json has a valid version field.

Method 2: Use bundleTypes.bundledPackages

If bundleTypes: true is enabled, you can instruct @microsoft/api-extractor to inline specific packages.

dts({
  bundleTypes: {
    bundledPackages: ['packageB', '@scope/*'],
  },
})

Limitations of Method 2:

• It forces all declarations into a single rolled-up file per entry, which is problematic for multi-entry libraries.
• It may fail to inline complex types (e.g., cross-file re-exports or Vue-specific types) with an "Unable to follow symbol" error.

When upgrading from vite-plugin-dts v4 to v5 (or moving to unplugin-dts v1), several breaking changes in configuration keys and import paths must be addressed.

Import Path Changes

While vite-plugin-dts maintains a compatibility layer for Vite, the recommended approach for v5 is to use unplugin-dts directly.

• Vite (Compatibility): import dts from 'vite-plugin-dts'
• Vite (Recommended): import dts from 'unplugin-dts/vite'
• Rollup: import dts from 'unplugin-dts/rollup'

Configuration Renames

Unchanged API

• editSourceMapDir: (content: string, fromDir: string, toDir: string) => string
• Resolver type: { name: string, supports: boolean, transform: ... }

// v5 (unplugin-dts, recommended)
import dts from 'unplugin-dts/vite'
import { type PluginOptions, editSourceMapDir } from 'unplugin-dts'

export { type PluginOptions, editSourceMapDir }

To use unplugin-dts with Rspack, import the plugin from unplugin-dts/rspack and add it to the plugins array in your rspack.config.mjs.

import { resolve } from 'node:path'
import { fileURLToPath } from 'node:url'
import { defineConfig } from '@rspack/cli'
import dts from 'unplugin-dts/rspack'

const rootDir = resolve(fileURLToPath(import.meta.url), '..')

export default defineConfig({
  entry: {
    index: './src/index.ts',
  },
  output: {
    path: resolve(rootDir, 'dist'),
  },
  module: {
    rules: [
      {
        test: /\.js$/,
        use: [
          {
            loader: 'builtin:swc-loader',
            options: {
              jsc: {
                parser: {
                  syntax: 'ecmascript',
                },
              },
            },
          },
        ],
      },
      {
        test: /\.ts$/,
        use: [
          {
            loader: 'builtin:swc-loader',
            options: {
              jsc: {
                parser: {
                  syntax: 'typescript',
                  decorators: true,
                },
              },
            },
          },
        ],
      },
    ],
  },
  plugins: [dts()],
})