fix(experimental-dts): make --experimental-dts to be compatible wit…

…h `--clean` (#1041)

src/api-extractor.ts

@@ -17,6 +17,7 @@ import {
   defaultOutExtension,
   ensureTempDeclarationDir,
   getApiExtractor,
+  removeFiles,
   toAbsolutePath,
   writeFileSync,
 } from './utils'
@@ -135,6 +136,12 @@ async function rollupDtsFiles(
   }
 }
 
+function cleanDtsFiles(options: NormalizedOptions) {
+  if (options.clean) {
+    removeFiles(['**/*.d.{ts,mts,cts}'], options.outDir)
+  }
+}
+
 export async function runDtsRollup(
   options: NormalizedOptions,
   exports?: ExportDeclaration[]
@@ -149,6 +156,7 @@ export async function runDtsRollup(
     if (!exports) {
       throw new Error('Unexpected internal error: dts exports is not define')
     }
+    cleanDtsFiles(options)
     for (const format of options.format) {
       await rollupDtsFiles(options, exports, format)
     }

src/index.ts

@@ -297,7 +297,7 @@ export async function build(_options: Options) {
                   : []
                 // .d.ts files are removed in the `dtsTask` instead
                 // `dtsTask` is a separate process, which might start before `mainTasks`
-                if (options.dts) {
+                if (options.dts || options.experimentalDts) {
                   extraPatterns.unshift('!**/*.d.{ts,cts,mts}')
                 }
                 await removeFiles(['**/*', ...extraPatterns], options.outDir)

test/index.test.ts

@@ -1668,3 +1668,50 @@ test('should only include exported declarations with experimentalDts', async ()
   expect(entry2dts).toContain('declare2')
   expect(entry2dts).not.toContain('declare1')
 })
+
+test('.d.ts files should be cleaned when --clean and --experimental-dts are provided', async () => {
+  const filesFoo = {
+    'package.json': `{ "name": "tsup-playground", "private": true }`,
+    'foo.ts': `export const foo = 1`,
+  }
+
+  const filesFooBar = {
+    ...filesFoo,
+    'bar.ts': `export const bar = 2`,
+  }
+
+  // First run with both foo and bar
+  const result1 = await run(getTestName(), filesFooBar, {
+    entry: ['foo.ts', 'bar.ts'],
+    flags: ['--experimental-dts'],
+  })
+
+  expect(result1.outFiles).toContain('foo.d.ts')
+  expect(result1.outFiles).toContain('foo.js')
+  expect(result1.outFiles).toContain('bar.d.ts')
+  expect(result1.outFiles).toContain('bar.js')
+
+  // Second run with only foo
+  const result2 = await run(getTestName(), filesFoo, {
+    entry: ['foo.ts'],
+    flags: ['--experimental-dts'],
+  })
+
+  // When --clean is not provided, the previous bar.* files should still exist
+  expect(result2.outFiles).toContain('foo.d.ts')
+  expect(result2.outFiles).toContain('foo.js')
+  expect(result2.outFiles).toContain('bar.d.ts')
+  expect(result2.outFiles).toContain('bar.js')
+
+  // Third run with only foo and --clean
+  const result3 = await run(getTestName(), filesFoo, {
+    entry: ['foo.ts'],
+    flags: ['--experimental-dts', '--clean'],
+  })
+
+  // When --clean is provided, the previous bar.* files should be deleted
+  expect(result3.outFiles).toContain('foo.d.ts')
+  expect(result3.outFiles).toContain('foo.js')
+  expect(result3.outFiles).not.toContain('bar.d.ts')
+  expect(result3.outFiles).not.toContain('bar.js')
+})