feat: add an option for preserving file extensions of .ts and .tsx files (#602)

Co-authored-by: Anthony Fu <github@antfu.me>

Author: bsdayo

README.md

@@ -326,6 +326,11 @@ AutoImport({
   // Default to 'append'
   dtsMode: 'append',
 
+  // Preserve the original file extensions in the generated .d.ts file.
+  // Set to `true` to keep the extensions for .ts and .tsx files.
+  // Default to false
+  dtsPreserveExts: false,
+
   // Array of strings of regexes that contains imports meant to be ignored during
   // the declaration file generation. You may find this useful when you need to provide
   // a custom signature for a function.

src/core/ctx.ts

@@ -22,6 +22,7 @@ export function createContext(options: Options = {}, root = process.cwd()) {
   const {
     dts: preferDTS = isPackageExists('typescript'),
     dtsMode = 'append',
+    dtsPreserveExts = false,
     dirsScanOptions,
     dirs,
     vueDirectives,
@@ -139,7 +140,11 @@ ${dts}`.trim()}\n`
     let currentContent = await unimport.generateTypeDeclarations({
       resolvePath: (i) => {
         if (i.from.startsWith('.') || isAbsolute(i.from)) {
-          const related = slash(relative(dir, i.from).replace(/\.ts(x)?$/, ''))
+          const related = slash(
+            dtsPreserveExts
+              ? relative(dir, i.from)
+              : relative(dir, i.from).replace(/\.ts(x)?$/, ''),
+          )
           return !related.startsWith('.')
             ? `./${related}`
             : related

src/types.ts

@@ -168,6 +168,13 @@ export interface Options {
    */
   dtsMode?: 'overwrite' | 'append'
 
+  /**
+   * Preserve the original file extensions in the generated .d.ts file.
+   * Set to `true` to keep the extensions for .ts and .tsx files.
+   * @default false
+   */
+  dtsPreserveExts?: boolean
+
   /**
    * Auto import inside Vue templates
    *