Migrate to ESM

.eslintrc

@@ -5,7 +5,8 @@
         "es6": true
     },
     "parserOptions": {
-        "ecmaVersion": 2018
+        "ecmaVersion": 2018,
+        "sourceType": "module"
     },
     "rules": {
         "no-duplicate-case": 2,

CHANGELOG.md

@@ -2,6 +2,7 @@
 
 - Allowed args after and between options
 - Replaced `chalk` with `ansi-colors`
+- Migrated to ESM
 
 ## 3.0.0-beta.1
 

lib/command.js

@@ -1,7 +1,7 @@
-const getCommandHelp = require('./help');
-const parseArgv = require('./parse-argv');
-const Params = require('./params');
-const Option = require('./option');
+import getCommandHelp from './help.js';
+import parseArgv from './parse-argv.js';
+import Params from './params.js';
+import Option from './option.js';
 
 const noop = () => {}; // nothing todo
 const self = value => value;
@@ -20,7 +20,7 @@ const handlers = ['init', 'applyConfig', 'finishContext', 'action'].reduce((res,
     return res;
 }, { initial: {}, setters: {} });
 
-module.exports = class Command {
+export default class Command {
     constructor(usage = '') {
         const [name, params] = usage.trim().split(/(\s+.*)$/);
 

lib/help.js

@@ -1,4 +1,4 @@
-const colors = require('ansi-colors');
+import colors from 'ansi-colors';
 
 const MAX_LINE_WIDTH = process.stdout.columns || 200;
 const MIN_OFFSET = 20;
@@ -115,7 +115,7 @@ function optionsHelp(command) {
  * @return {String}
  * @api private
  */
-module.exports = function getCommandHelp(command, commandPath) {
+export default function getCommandHelp(command, commandPath) {
     commandPath = Array.isArray(commandPath) && commandPath.length
         ? commandPath.concat(command.name).join(' ')
         : command.name;

lib/index.js

@@ -1,24 +1,26 @@
-const path = require('path');
-const Params = require('./params');
-const Option = require('./option');
-const Command = require('./command');
-const Error = require('./parse-argv-error');
-const getCommandHelp = require('./help');
+import { basename, extname } from 'path';
+import Params from './params.js';
+import Option from './option.js';
+import Command from './command.js';
+import Error from './parse-argv-error.js';
+import getCommandHelp from './help.js';
 
 function nameFromProcessArgv() {
-    return path.basename(process.argv[1], path.extname(process.argv[1]));
+    return basename(process.argv[1], extname(process.argv[1]));
 }
 
-module.exports = {
+function command(name, params, config) {
+    name = name || nameFromProcessArgv() || 'command';
+
+    return new Command(name, params, config);
+}
+
+export {
     Error,
     Params,
     Command,
     Option,
 
     getCommandHelp,
-    command: function(name, params, config) {
-        name = name || nameFromProcessArgv() || 'command';
-
-        return new Command(name, params, config);
-    }
+    command
 };

lib/option.js

@@ -1,9 +1,10 @@
-const Params = require('./params');
+import Params from './params.js';
+
 const camelcase = name => name.replace(/-(.)/g, (m, ch) => ch.toUpperCase());
 const ensureFunction = (fn, fallback) => typeof fn === 'function' ? fn : fallback;
 const self = value => value;
 
-module.exports = class Option {
+export default class Option {
     static normalizeOptions(opt1, opt2) {
         const raw = typeof opt1 === 'function'
             ? { normalize: opt1, default: opt2 }

lib/params.js

@@ -1,4 +1,4 @@
-module.exports = class Params {
+export default class Params {
     constructor(params = '', context) {
         // params = ..<required> ..[optional]
         // <foo> - required

lib/parse-argv-error.js

@@ -1,4 +1,4 @@
-module.exports = class CliError extends Error {
+export default class CliError extends Error {
     constructor(...args) {
         super(...args);
         this.name = 'CliError';

lib/parse-argv.js

@@ -1,4 +1,4 @@
-const CliError = require('./parse-argv-error');
+import CliError from './parse-argv-error.js';
 
 function findVariants(command, entry) {
     return [
@@ -47,7 +47,7 @@ function consumeOptionParams(option, rawOptions, argv, index, suggestPoint) {
     return index + tokens.length - 1;
 }
 
-module.exports = function parseArgv(command, argv, context, suggestMode) {
+export default function parseArgv(command, argv, context, suggestMode) {
     const suggestPoint = suggestMode ? argv.length - 1 : -1;
     const rawOptions = [];
     const result = {

package.json

@@ -13,7 +13,15 @@
     "argument",
     "completion"
   ],
+  "type": "module",
   "main": "lib/index.js",
+  "exports": {
+    ".": {
+      "import": "./lib/index.js",
+      "require": "./cjs/index.cjs"
+    },
+    "./package.json": "./package.json"
+  },
   "files": [
     "lib"
   ],

test/command-action.js

@@ -1,13 +1,12 @@
-const assert = require('assert');
-const cli = require('../lib');
+import { equal, notDeepEqual, deepEqual } from 'assert';
+import * as clap from 'clap';
 
-describe('action()', function() {
-    it('should have an expected input', function() {
+describe('action()', () => {
+    it('should have an expected input', () => {
         const calls = [];
-        const command = cli
-            .command('test [foo]')
+        const command = clap.command('test [foo]')
             .option('--bar', 'bar option')
-            .action(function(...args) {
+            .action((...args) => {
                 calls.push({
                     this: this,
                     arguments: args
@@ -16,9 +15,9 @@ describe('action()', function() {
 
         command.run(['abc', '--', 'rest', 'args']);
 
-        assert.equal(calls.length, 1);
-        assert.notDeepEqual(calls[0].this, command);
-        assert.deepEqual(calls[0].arguments, [{
+        equal(calls.length, 1);
+        notDeepEqual(calls[0].this, command);
+        deepEqual(calls[0].arguments, [{
             commandPath: ['test'],
             options: { bar: false },
             args: ['abc'],

test/command-args-and-options.js

@@ -1,20 +1,20 @@
-const assert = require('assert');
-const cli = require('../lib');
+import { deepStrictEqual, throws, equal } from 'assert';
+import * as clap from 'clap';
 
-describe('command run', function() {
+describe('command run', () => {
     describe('args and options', () => {
         let command;
 
-        beforeEach(function() {
-            command = cli.command('test [foo]')
+        beforeEach(() => {
+            command = clap.command('test [foo]')
                 .option('--foo', 'Foo')
                 .option('--bar <number>', 'Bar', Number);
         });
 
-        it('no arguments', function() {
+        it('no arguments', () => {
             const actual = command.run([]);
 
-            assert.deepStrictEqual(actual, {
+            deepStrictEqual(actual, {
                 commandPath: ['test'],
                 options: {
                     __proto__: null,
@@ -25,10 +25,10 @@ describe('command run', function() {
             });
         });
 
-        it('args', function() {
+        it('args', () => {
             const actual = command.run(['qux']);
 
-            assert.deepStrictEqual(actual, {
+            deepStrictEqual(actual, {
                 commandPath: ['test'],
                 options: {
                     __proto__: null,
@@ -39,10 +39,10 @@ describe('command run', function() {
             });
         });
 
-        it('options', function() {
+        it('options', () => {
             const actual = command.run(['--foo', '--bar', '123']);
 
-            assert.deepStrictEqual(actual, {
+            deepStrictEqual(actual, {
                 commandPath: ['test'],
                 options: {
                     __proto__: null,
@@ -54,10 +54,10 @@ describe('command run', function() {
             });
         });
 
-        it('literal args', function() {
+        it('literal args', () => {
             const actual = command.run(['--', '--one', '--two', '123']);
 
-            assert.deepStrictEqual(actual, {
+            deepStrictEqual(actual, {
                 commandPath: ['test'],
                 options: {
                     __proto__: null,
@@ -68,10 +68,10 @@ describe('command run', function() {
             });
         });
 
-        it('args & options', function() {
+        it('args & options', () => {
             const actual = command.run(['qux', '--foo', '--bar', '123']);
 
-            assert.deepStrictEqual(actual, {
+            deepStrictEqual(actual, {
                 commandPath: ['test'],
                 options: {
                     __proto__: null,
@@ -83,10 +83,10 @@ describe('command run', function() {
             });
         });
 
-        it('args & options before', function() {
+        it('args & options before', () => {
             const actual = command.run(['--foo', '--bar', '123', 'qux']);
 
-            assert.deepStrictEqual(actual, {
+            deepStrictEqual(actual, {
                 commandPath: ['test'],
                 options: {
                     __proto__: null,
@@ -98,10 +98,10 @@ describe('command run', function() {
             });
         });
 
-        it('args & literal args', function() {
+        it('args & literal args', () => {
             const actual = command.run(['qux', '--', '--one', '--two', '123']);
 
-            assert.deepStrictEqual(actual, {
+            deepStrictEqual(actual, {
                 commandPath: ['test'],
                 options: {
                     __proto__: null,
@@ -112,10 +112,10 @@ describe('command run', function() {
             });
         });
 
-        it('options & literal args', function() {
+        it('options & literal args', () => {
             const actual = command.run(['--foo', '--bar', '123', '--', '--one', '--two', '123']);
 
-            assert.deepStrictEqual(actual, {
+            deepStrictEqual(actual, {
                 commandPath: ['test'],
                 options: {
                     __proto__: null,
@@ -127,10 +127,10 @@ describe('command run', function() {
             });
         });
 
-        it('args & options & literal args', function() {
+        it('args & options & literal args', () => {
             const actual = command.run(['qux', '--foo', '--bar', '123', '--', '--one', '--two', '123']);
 
-            assert.deepStrictEqual(actual, {
+            deepStrictEqual(actual, {
                 commandPath: ['test'],
                 options: {
                     __proto__: null,
@@ -145,12 +145,12 @@ describe('command run', function() {
 
     describe('multi arg option', () => {
         it('x', () => {
-            const command = cli.command()
+            const command = clap.command()
                 .option('--option <arg1> [arg2]', 'description', function(value, oldValue) {
                     return (oldValue || []).concat(value);
                 });
 
-            assert.deepStrictEqual(
+            deepStrictEqual(
                 command.run(['--option','foo', 'bar', '--option', 'baz']).options,
                 {
                     __proto__: null,
@@ -162,36 +162,36 @@ describe('command run', function() {
 
     describe('required argument', () => {
         let action;
-        const command = cli
+        const command = clap
             .command('test <arg1>')
             .action(() => action = '1')
             .command('nested <arg2>')
             .action(() => action = '2')
             .end();
 
-        beforeEach(function() {
+        beforeEach(() => {
             action = '';
         });
 
-        it('should throw exception if no first argument', function() {
-            assert.throws(
+        it('should throw exception if no first argument', () => {
+            throws(
                 () => command.run([]),
                 /Missed required argument\(s\) for command "test"/
             );
         });
-        it('should throw exception if no second argument', function() {
-            assert.throws(
+        it('should throw exception if no second argument', () => {
+            throws(
                 () => command.run(['one', 'nested']),
                 /Missed required argument\(s\) for command "nested"/
             );
         });
-        it('should treat first argument as value', function() {
+        it('should treat first argument as value', () => {
             command.run(['nested']);
-            assert.equal(action, '1');
+            equal(action, '1');
         });
-        it('should run nested action', function() {
+        it('should run nested action', () => {
             command.run(['one', 'nested', 'two']);
-            assert.equal(action, '2');
+            equal(action, '2');
         });
     });
 });