Add support for ES modules

Signed-off-by: Jon Koops <jonkoops@gmail.com>

index.d.mts

@@ -0,0 +1,3 @@
+export function byteLength(b64: string): number;
+export function toByteArray(b64: string): Uint8Array;
+export function fromByteArray(uint8: Uint8Array): string;

index.js → index.mjs

@@ -1,9 +1,3 @@
-'use strict'
-
-exports.byteLength = byteLength
-exports.toByteArray = toByteArray
-exports.fromByteArray = fromByteArray
-
 var lookup = []
 var revLookup = []
 var Arr = typeof Uint8Array !== 'undefined' ? Uint8Array : Array
@@ -39,7 +33,7 @@ function getLens (b64) {
 }
 
 // base64 is 4/3 + up to two characters of the original data
-function byteLength (b64) {
+export function byteLength (b64) {
   var lens = getLens(b64)
   var validLen = lens[0]
   var placeHoldersLen = lens[1]
@@ -50,7 +44,7 @@ function _byteLength (b64, validLen, placeHoldersLen) {
   return ((validLen + placeHoldersLen) * 3 / 4) - placeHoldersLen
 }
 
-function toByteArray (b64) {
+export function toByteArray (b64) {
   var tmp
   var lens = getLens(b64)
   var validLen = lens[0]
@@ -116,7 +110,7 @@ function encodeChunk (uint8, start, end) {
   return output.join('')
 }
 
-function fromByteArray (uint8) {
+export function fromByteArray (uint8) {
   var tmp
   var len = uint8.length
   var extraBytes = len % 3 // if we have 1 byte left, pad 2 bytes

package.json

@@ -33,24 +33,38 @@
   "files": [
     "base64js.min.js",
     "index.d.ts",
-    "index.js"
+    "index.d.mts",
+    "index.js",
+    "index.mjs"
   ],
   "main": "index.js",
   "typings": "index.d.ts",
+  "exports": {
+    ".": {
+      "import": {
+        "types": "./index.d.mts",
+        "default": "./index.mjs"
+      },
+      "require": {
+        "types": "./index.d.ts",
+        "default": "./index.js"
+      }
+    }
+  },
   "repository": {
     "type": "git",
     "url": "git+https://github.com/feross/base64-js.git"
   },
   "scripts": {
-    "build": "browserify -s base64js -r ./ | minify > base64js.min.js",
-    "lint": "standard",
+    "build": "rollup index.mjs --file index.js --format cjs && rollup index.js --file base64js.min.js --format umd --name base64js --plugin terser",
+    "lint": "standard --ignore index.js --ignore base64js.min.js",
     "test": "npm run lint && npm run unit",
     "unit": "tape test/*.js"
   },
   "devDependencies": {
-    "babel-minify": "^0.5.1",
+    "@rollup/plugin-terser": "^0.4.4",
     "benchmark": "^2.1.4",
-    "browserify": "^17.0.0",
+    "rollup": "^4.19.0",
     "standard": "*",
     "tape": "^5.4.0"
   }