From dd694b62f62fdc0d67c3dac94e0ee16fd2f6040e Mon Sep 17 00:00:00 2001
From: "Benjamin E. Coe" <bencoe@google.com>
Date: Wed, 26 Aug 2020 21:47:46 -0700
Subject: [PATCH] build: use ts-transform-default-export for index.d.ts (#304)

---
 package.json                      |  2 +-
 rollup.config.js                  |  7 ++++++-
 scripts/replace-legacy-export.cjs | 11 -----------
 3 files changed, 7 insertions(+), 13 deletions(-)
 delete mode 100755 scripts/replace-legacy-export.cjs

diff --git a/package.json b/package.json
index 762b123e..c53042e6 100644
--- a/package.json
+++ b/package.json
@@ -24,7 +24,6 @@
     "compile": "tsc",
     "postcompile": "npm run build:cjs",
     "build:cjs": "rollup -c",
-    "postbuild:cjs": "node scripts/replace-legacy-export.cjs",
     "prepare": "npm run compile"
   },
   "repository": {
@@ -65,6 +64,7 @@
     "serve": "^11.3.2",
     "standardx": "^5.0.0",
     "start-server-and-test": "^1.11.2",
+    "ts-transform-default-export": "^1.0.2",
     "typescript": "^4.0.0"
   },
   "files": [
diff --git a/rollup.config.js b/rollup.config.js
index 935ebda1..a1dbd5c9 100644
--- a/rollup.config.js
+++ b/rollup.config.js
@@ -1,4 +1,5 @@
 import ts from '@wessberg/rollup-plugin-ts'
+import transformDefaultExport from 'ts-transform-default-export'
 
 const output = {
   format: 'cjs',
@@ -12,6 +13,10 @@ export default {
   input: './lib/index.ts',
   output,
   plugins: [
-    ts({ /* options */ })
+    ts({
+      transformers: ({ program }) => ({
+        afterDeclarations: transformDefaultExport(program)
+      })
+    })
   ]
 }
diff --git a/scripts/replace-legacy-export.cjs b/scripts/replace-legacy-export.cjs
deleted file mode 100755
index c4af84bd..00000000
--- a/scripts/replace-legacy-export.cjs
+++ /dev/null
@@ -1,11 +0,0 @@
-#!/usr/bin/env node
-'use strict'
-
-const { readFileSync, writeFileSync } = require('fs')
-
-// Cleanup the export statement in CJS typings file generated by rollup:
-const legacyTypings = require('path').resolve(__dirname, '../build/index.cjs.d.ts')
-const contents = readFileSync(legacyTypings, 'utf8').replace(
-  'export { yargsParser as default };', 'export = yargsParser;'
-)
-writeFileSync(legacyTypings, contents, 'utf8')