feat: allow post-processing generated DTS file

docs/guide/configuration.md

@@ -68,6 +68,11 @@ VueRouter({
   async beforeWriteFiles(rootRoute) {
     // ...
   },
+
+  // modify the generated DTS file before written to disk
+  async postProcessDTS(dts) {
+    // ...
+  },
 })
 ```
 

e2e/routes.spec.ts

@@ -1,6 +1,7 @@
 import { describe, expect, it } from 'vitest'
 import { createRoutesContext } from '../src/core/context'
 import { resolveOptions } from '../src/options'
+import { readFileSync } from 'node:fs'
 import { fileURLToPath, URL } from 'node:url'
 import { normalize, join } from 'pathe'
 
@@ -34,6 +35,23 @@ describe('e2e routes', () => {
     ).toMatchSnapshot()
   })
 
+  it('allows post-processing the generated DTS file', async () => {
+    const suffix = `export type Foo = 'bar'`
+    const dts = join(__dirname, './.types/__types.d.ts')
+    const context = createRoutesContext(
+      resolveOptions({
+        dts,
+        logs: false,
+        watch: false,
+        routesFolder: [{ src: join(__dirname, './fixtures/filenames/routes') }],
+        postProcessDTS: (dts) => `${dts}\n${suffix}\n`,
+      })
+    )
+
+    await context.scanPages()
+    expect(readFileSync(dts, 'utf-8')).toContain(suffix)
+  })
+
   it.skip('works with mixed extensions', async () => {
     const context = createRoutesContext(
       resolveOptions({

src/core/context.ts

@@ -263,7 +263,12 @@ if (import.meta.hot) {
 
     logTree(routeTree, logger.log)
     if (dts) {
-      const content = generateDTS()
+      let content = generateDTS()
+
+      if (options.postProcessDTS) {
+        content = await options.postProcessDTS(content)
+      }
+
       if (lastDTS !== content) {
         await fs.mkdir(dirname(dts), { recursive: true })
         await fs.writeFile(dts, content, 'utf-8')

src/options.ts

@@ -163,6 +163,11 @@ export interface Options {
    */
   beforeWriteFiles?: (rootRoute: EditableTreeNode) => _Awaitable<void>
 
+  /**
+   * Allows to post-process the generated d.ts files. This will be invoked **every time** the d.ts file needs to be written.
+   */
+  postProcessDTS?: (dts: string) => _Awaitable<string>
+
   /**
    * Defines how page components should be imported. Defaults to dynamic imports to enable lazy loading of pages.
    * @default `'async'`