feat: support ESM (#70)

build.ts

@@ -0,0 +1,73 @@
+/*
+ This script is heavily inspired by `built.ts` used in @kaze-style/react.
+ https://github.com/taishinaritomi/kaze-style/blob/main/scripts/build.ts
+ MIT License
+ Copyright (c) 2022 Taishi Naritomi
+*/
+
+import { exec } from 'child_process'
+import fs from 'fs'
+import path from 'path'
+import { build } from 'esbuild'
+import type { Plugin, PluginBuild, BuildOptions } from 'esbuild'
+import glob from 'glob'
+
+const entryPoints = glob.sync('./src/**/*.ts', {
+ ignore: ['./src/types.ts'],
+})
+
+/*
+ This plugin is inspired by the following.
+ https://github.com/evanw/esbuild/issues/622#issuecomment-769462611
+*/
+const addExtension = (extension: string = '.js', fileExtension: string = '.ts'): Plugin => ({
+ name: 'add-extension',
+ setup(build: PluginBuild) {
+ build.onResolve({ filter: /.*/ }, (args) => {
+ if (args.importer) {
+ const p = path.join(args.resolveDir, args.path)
+ let tsPath = `${p}${fileExtension}`
+
+ let importPath = ''
+ if (fs.existsSync(tsPath)) {
+ importPath = args.path + extension
+ } else {
+ tsPath = path.join(args.resolveDir, args.path, `index${fileExtension}`)
+ if (fs.existsSync(tsPath)) {
+ importPath = `${args.path}/index${extension}`
+ }
+ }
+ return { path: importPath, external: true }
+ }
+ })
+ },
+})
+
+const commonOptions: BuildOptions = {
+ entryPoints,
+ logLevel: 'info',
+ platform: 'node',
+}
+
+const cjsBuild = () =>
+ build({
+ ...commonOptions,
+ outbase: './src',
+ outdir: './dist',
+ format: 'cjs',
+ })
+
+const esmBuild = () =>
+ build({
+ ...commonOptions,
+ bundle: true,
+ outbase: './src',
+ outdir: './dist',
+ format: 'esm',
+ outExtension: { '.js': '.mjs' },
+ plugins: [addExtension('.mjs')],
+ })
+
+Promise.all([esmBuild(), cjsBuild()])
+
+exec(`tsc --emitDeclarationOnly --declaration`)

package.json

@@ -10,10 +10,19 @@
  "exports": {
  ".": {
  "types": "./dist/index.d.ts",
- "default": "./dist/index.js"
+ "require": "./dist/index.js",
+ "import": "./dist/index.mjs"
  },
- "./serve-static": "./dist/serve-static.js",
- "./vercel": "./dist/vercel.js"
+ "./serve-static": {
+ "types": "./dist/serve-static.d.ts",
+ "require": "./dist/serve-static.js",
+ "import": "./dist/serve-static.mjs"
+ },
+ "./vercel": {
+ "types": "./dist/vercel.d.ts",
+ "require": "./dist/vercel.js",
+ "import": "./dist/vercel.mjs"
+ }
  },
  "typesVersions": {
  "*": {
@@ -30,7 +39,7 @@
  },
  "scripts": {
  "test": "jest",
- "build": "rimraf dist && tsc",
+ "build": "rimraf dist && tsx ./build.ts",
  "postbuild": "publint",
  "prerelease": "yarn build && yarn test",
  "release": "np"
@@ -51,16 +60,19 @@
  },
  "dependencies": {},
  "devDependencies": {
+ "@types/glob": "^8.1.0",
  "@types/jest": "^29.5.3",
  "@types/node": "^18.7.16",
  "@types/supertest": "^2.0.12",
+ "esbuild": "^0.18.13",
  "hono": "^3.3.0",
  "jest": "^29.6.1",
  "np": "^7.7.0",
  "publint": "^0.1.16",
  "rimraf": "^3.0.2",
  "supertest": "^6.2.4",
  "ts-jest": "^29.1.1",
+ "tsx": "^3.12.7",
  "typescript": "^4.8.3"
  }
-}
+}