chore: migrate to esm modules

Author: mjeanroy

.babelrc

@@ -1,5 +1,25 @@
 {
   "presets": [
-    "@babel/preset-env"
-  ]
+    [
+      "@babel/preset-env", {
+        "modules": "cjs"
+      }
+    ]
+  ],
+
+  "plugins": [
+    "add-module-exports"
+  ],
+
+  "env": {
+    "es": {
+      "presets": [
+        [
+          "@babel/preset-env", {
+            "modules": "false"
+          }
+        ]
+      ]
+    }
+  }
 }

package.json

@@ -2,7 +2,16 @@
   "name": "rollup-plugin-esformatter",
   "version": "0.7.0",
   "description": "Rollup plugin to beautify bundle with esformatter",
-  "main": "dist/index.js",
+  "main": "dist/cjs/index.js",
+  "module": "dist/es/index.js",
+  "exports": {
+    ".": {
+      "require": "./dist/cjs/index.js",
+      "import": "./dist/es/index.js",
+      "default": "./dist/index.js"
+    },
+    "./dist/": "./dist/"
+  },
   "scripts": {
     "clean": "gulp clean",
     "lint": "gulp lint",
@@ -42,6 +51,7 @@
     "@babel/core": "7.8.7",
     "@babel/preset-env": "7.8.7",
     "@babel/register": "7.8.6",
+    "babel-plugin-add-module-exports": "^1.0.2",
     "eslint": "6.8.0",
     "eslint-config-google": "0.14.0",
     "fancy-log": "1.3.3",
@@ -51,8 +61,10 @@
     "gulp-conventional-changelog": "2.0.29",
     "gulp-eslint": "6.0.0",
     "gulp-git": "2.10.0",
+    "gulp-header-comment": "0.6.1",
     "gulp-jasmine": "4.0.0",
     "gulp-prettier": "2.3.0",
+    "gulp-strip-banner": "0.0.2",
     "jasmine-core": "3.5.0",
     "q": "1.5.1",
     "rimraf": "3.0.2",

scripts/build/index.js

@@ -25,12 +25,45 @@
 const path = require('path');
 const gulp = require('gulp');
 const babel = require('gulp-babel');
+const stripBanner = require('gulp-strip-banner');
+const headerComment = require('gulp-header-comment');
 const prettier = require('gulp-prettier');
 const config = require('../config');
 
-module.exports = function build() {
+module.exports = gulp.series(
+    buildCjs,
+    buildEsm
+);
+
+/**
+ * Build CommonJS bundles.
+ *
+ * @return {NodeJS.WritableStream} The gulp stream.
+ */
+function buildCjs() {
+  return build('cjs');
+}
+
+/**
+ * Build ESM bundles.
+ *
+ * @return {NodeJS.WritableStream} The gulp stream.
+ */
+function buildEsm() {
+  return build('es');
+}
+
+/**
+ * Build bundle for given environment.
+ *
+ * @param {string} envName Environment id.
+ * @return {NodeJS.WritableStream} The gulp stream.
+ */
+function build(envName) {
   return gulp.src(path.join(config.src, '**', '*.js'))
-      .pipe(babel())
+      .pipe(stripBanner())
+      .pipe(babel({envName}))
+      .pipe(headerComment({file: path.join(config.root, 'LICENSE')}))
       .pipe(prettier())
-      .pipe(gulp.dest(config.dist));
-};
+      .pipe(gulp.dest(path.join(config.dist, envName)));
+}

src/.eslintrc

@@ -0,0 +1,6 @@
+{
+  "parserOptions": {
+    "sourceType": "module"
+  }
+}
+  

src/index-rollup-legacy.js

@@ -22,13 +22,11 @@
  * SOFTWARE.
  */
 
-'use strict';
+import hasIn from 'lodash.hasin';
+import isNil from 'lodash.isnil';
+import RollupPluginEsFormatter from './rollup-plugin-esformatter.js';
 
-const hasIn = require('lodash.hasin');
-const isNil = require('lodash.isnil');
-const RollupPluginEsFormatter = require('./rollup-plugin-esformatter.js');
-
-module.exports = (options) => {
+export default (options) => {
   const plugin = new RollupPluginEsFormatter(options);
 
   return {

src/index-rollup-stable.js

@@ -22,11 +22,9 @@
  * SOFTWARE.
  */
 
-'use strict';
+import RollupPluginEsFormatter from './rollup-plugin-esformatter.js';
 
-const RollupPluginEsFormatter = require('./rollup-plugin-esformatter.js');
-
-module.exports = (options) => {
+export default (options) => {
   const plugin = new RollupPluginEsFormatter(options);
 
   return {

src/index.js

@@ -22,10 +22,13 @@
  * SOFTWARE.
  */
 
-'use strict';
+import {rollup} from 'rollup';
+import legacy from './index-rollup-legacy.js';
+import stable from './index-rollup-stable.js';
 
-const rollup = require('rollup');
 const VERSION = rollup.VERSION || '0';
 const MAJOR_VERSION = Number(VERSION.split('.')[0]) || 0;
 const IS_ROLLUP_LEGACY = MAJOR_VERSION === 0;
-module.exports = IS_ROLLUP_LEGACY ? require('./index-rollup-legacy.js') : require('./index-rollup-stable.js');
+const esformatter = IS_ROLLUP_LEGACY ? legacy : stable;
+
+export default esformatter;

src/rollup-plugin-esformatter.js

@@ -22,15 +22,13 @@
  * SOFTWARE.
  */
 
-'use strict';
-
-const omitBy = require('lodash.omitby');
-const isEmpty = require('lodash.isempty');
-const hasIn = require('lodash.hasin');
-const isNil = require('lodash.isnil');
-const MagicString = require('magic-string');
-const diff = require('diff');
-const esformatter = require('esformatter');
+import omitBy from 'lodash.omitby';
+import isEmpty from 'lodash.isempty';
+import hasIn from 'lodash.hasin';
+import isNil from 'lodash.isnil';
+import MagicString from 'magic-string';
+import {diffChars} from 'diff';
+import esformatter from 'esformatter';
 
 /**
  * The internal plugin options.
@@ -43,7 +41,7 @@ const OPTIONS = new Set([
 /**
  * The rollup plugin for ESFormatter.
  */
-module.exports = class RollupPluginEsFormatter {
+export default class RollupPluginEsFormatter {
   /**
    * Initialize plugin.
    *
@@ -113,7 +111,7 @@ module.exports = class RollupPluginEsFormatter {
     console.warn(`[${this.name}] This may take a moment (depends on the size of your bundle)`);
 
     const magicString = new MagicString(source);
-    const changes = diff.diffChars(source, output);
+    const changes = diffChars(source, output);
 
     let idx = 0;
 
@@ -137,4 +135,4 @@ module.exports = class RollupPluginEsFormatter {
       }),
     };
   }
-};
+}

test/.eslintrc

@@ -1,6 +1,8 @@
 {
+  "parserOptions": {
+    "sourceType": "module"
+  },
   "env": {
     "jasmine": true
   }
 }
-  

test/index-rollup-legacy.spec.js

@@ -22,12 +22,10 @@
  * SOFTWARE.
  */
 
-'use strict';
-
-const esformatter = require('esformatter');
-const verifyWarnLogsBecauseOfSourcemap = require('./utils/verify-warn-logs-because-of-source-map.js');
-const verifyWarnLogsNotTriggered = require('./utils/verify-warn-logs-not-triggered.js');
-const plugin = require('../src/index-rollup-legacy.js');
+import esformatter from 'esformatter';
+import verifyWarnLogsBecauseOfSourcemap from './utils/verify-warn-logs-because-of-source-map.js';
+import verifyWarnLogsNotTriggered from './utils/verify-warn-logs-not-triggered.js';
+import plugin from '../src/index-rollup-legacy.js';
 
 describe('rollup-plugin-esformatter [legacy]', () => {
   beforeEach(() => {

test/index-rollup-stable.spec.js

@@ -24,10 +24,10 @@
 
 'use strict';
 
-const esformatter = require('esformatter');
-const verifyWarnLogsBecauseOfSourcemap = require('./utils/verify-warn-logs-because-of-source-map.js');
-const verifyWarnLogsNotTriggered = require('./utils/verify-warn-logs-not-triggered.js');
-const plugin = require('../src/index-rollup-stable.js');
+import esformatter from 'esformatter';
+import verifyWarnLogsBecauseOfSourcemap from './utils/verify-warn-logs-because-of-source-map.js';
+import verifyWarnLogsNotTriggered from './utils/verify-warn-logs-not-triggered.js';
+import plugin from '../src/index-rollup-stable.js';
 
 describe('rollup-plugin-esformatter [stable]', () => {
   beforeEach(() => {

test/it/it.spec.js

@@ -22,15 +22,13 @@
  * SOFTWARE.
  */
 
-'use strict';
-
-const fs = require('fs');
-const path = require('path');
-const rollup = require('rollup');
-const tmp = require('tmp');
-const Q = require('q');
-const verifyWarnLogsBecauseOfSourcemap = require('../utils/verify-warn-logs-because-of-source-map.js');
-const esformatter = require('../../src/index.js');
+import fs from 'fs';
+import path from 'path';
+import * as rollup from 'rollup';
+import tmp from 'tmp';
+import Q from 'q';
+import verifyWarnLogsBecauseOfSourcemap from '../utils/verify-warn-logs-because-of-source-map.js';
+import esformatter from '../../src/index.js';
 
 describe('rollup-plugin-esformatter', () => {
   let tmpDir;

test/rollup-plugin-esformatter.spec.js

@@ -24,9 +24,9 @@
 
 'use strict';
 
-const RollupPluginEsFormatter = require('../src/rollup-plugin-esformatter.js');
-const verifyWarnLogsBecauseOfSourcemap = require('./utils/verify-warn-logs-because-of-source-map.js');
-const verifyWarnLogsNotTriggered = require('./utils/verify-warn-logs-not-triggered.js');
+import RollupPluginEsFormatter from '../src/rollup-plugin-esformatter.js';
+import verifyWarnLogsBecauseOfSourcemap from './utils/verify-warn-logs-because-of-source-map.js';
+import verifyWarnLogsNotTriggered from './utils/verify-warn-logs-not-triggered.js';
 
 describe('RollupPluginEsFormatter', () => {
   beforeEach(() => {

test/utils/verify-warn-logs-because-of-source-map.js

@@ -27,12 +27,12 @@
  *
  * @return {void}
  */
-module.exports = function verifyWarnLogsBecauseOfSourcemap() {
+export default function verifyWarnLogsBecauseOfSourcemap() {
   expect(console.warn).toHaveBeenCalledWith(
       '[rollup-plugin-esformatter] Sourcemap is enabled, computing diff is required'
   );
 
   expect(console.warn).toHaveBeenCalledWith(
       '[rollup-plugin-esformatter] This may take a moment (depends on the size of your bundle)'
   );
-};
+}

test/utils/verify-warn-logs-not-triggered.js

@@ -27,12 +27,12 @@
  *
  * @return {void}
  */
-module.exports = function verifyWarnLogsNotTriggered() {
+export default function verifyWarnLogsNotTriggered() {
   expect(console.warn).not.toHaveBeenCalledWith(
       '[rollup-plugin-esformatter] Sourcemap is enabled, computing diff is required'
   );
 
   expect(console.warn).not.toHaveBeenCalledWith(
       '[rollup-plugin-esformatter] This may take a moment (depends on the size of your bundle)'
   );
-};
+}