Add ESM build for browsers (#342)

evanw · Oct 18, 2020 · cfaedae · cfaedae
1 parent 40c1e14
commit cfaedae
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Showing 3 changed files with 27 additions and 6 deletions.
diff --git a/lib/browser.ts b/lib/browser.ts
@@ -3,23 +3,23 @@ import * as common from "./common"
 
 declare let WEB_WORKER_SOURCE_CODE: string
 
-let build: typeof types.build = options => {
+export const build: typeof types.build = options => {
   throw new Error(`The "build" API only works in node`);
 };
 
-let transform: typeof types.transform = (input, options) => {
+export const transform: typeof types.transform = (input, options) => {
   throw new Error(`The "transform" API only works in node`);
 };
 
-let buildSync: typeof types.buildSync = options => {
+export const buildSync: typeof types.buildSync = options => {
   throw new Error(`The "buildSync" API only works in node`);
 };
 
-let transformSync: typeof types.transformSync = (input, options) => {
+export const transformSync: typeof types.transformSync = (input, options) => {
   throw new Error(`The "transformSync" API only works in node`);
 };
 
-let startService: typeof types.startService = options => {
+export const startService: typeof types.startService = options => {
   if (!options) throw new Error('Must provide an options object to "startService"');
   if (!options.wasmURL) throw new Error('Must provide the "wasmURL" option');
   return fetch(options.wasmURL).then(r => r.arrayBuffer()).then(wasm => {
@@ -87,4 +87,4 @@ let api: typeof types = {
   startService,
 };
 
-module.exports = api;
+export default api
diff --git a/npm/esbuild-wasm/package.json b/npm/esbuild-wasm/package.json
@@ -9,6 +9,17 @@
   },
   "main": "lib/main.js",
   "browser": "lib/browser.js",
+  "module": "lib/browser.mjs",
+  "exports": {
+    ".": {
+      "browser": {
+        "module": "./lib/browser.mjs",
+        "script": "./lib/browser.js"
+      },
+      "node": "./lib/main.js"
+    },
+    "./": "./"
+  },
   "types": "lib/main.d.ts",
   "directories": {
     "bin": "bin"

diff --git a/scripts/esbuild.js b/scripts/esbuild.js
@@ -95,6 +95,16 @@ function buildWasmLib(esbuildPath) {
     '--define:WEB_WORKER_SOURCE_CODE=' + JSON.stringify(wasmExecMinCode + workerMinCode),
   ], { cwd: repoDir }).toString()
   fs.writeFileSync(path.join(libDir, 'browser.js'), umdPrefix + browserJs.trim() + umdSuffix)
+
+  // Generate "npm/esbuild-wasm/browser.mjs"
+  const browserMjs = childProcess.execFileSync(esbuildPath, [
+    path.join(repoDir, 'lib', 'browser.ts'),
+    '--bundle',
+    '--target=es2020',
+    '--format=esm',
+    '--define:WEB_WORKER_SOURCE_CODE=' + JSON.stringify(wasmExecMinCode + workerMinCode),
+  ], { cwd: repoDir }).toString()
+  fs.writeFileSync(path.join(libDir, 'browser.mjs'), browserMjs.trim())
 }
 
 exports.buildBinary = () => {