Use Rollup for bundling dependencies

.gitignore

@@ -1,2 +1,3 @@
 node_modules
+build
 yarn.lock

package.json

@@ -13,16 +13,20 @@
 	"type": "module",
 	"exports": {
 		"types": "./index.d.ts",
-		"default": "./source/index.js"
+		"default": "./build/index.js"
 	},
+	"sideEffects": false,
 	"engines": {
 		"node": ">=16.10"
 	},
 	"scripts": {
-		"test": "xo && ava && tsd"
+		"prepare": "npm run build",
+		"build": "rollup --config",
+		"test": "xo && ava && tsd && npm run test:build",
+		"test:build": "npm run build && ava test/build.js"
 	},
 	"files": [
-		"source",
+		"build",
 		"index.d.ts"
 	],
 	"keywords": [
@@ -44,38 +48,60 @@
 		"cmd",
 		"console"
 	],
-	"dependencies": {
+	"_actualDependencies": [
+		"@types/minimist",
+		"camelcase-keys",
+		"decamelize",
+		"decamelize-keys",
+		"hard-rejection",
+		"minimist-options",
+		"normalize-package-data",
+		"read-pkg-up",
+		"redent",
+		"trim-newlines",
+		"type-fest",
+		"yargs-parser"
+	],
+	"devDependencies": {
+		"@rollup/plugin-commonjs": "^25.0.3",
+		"@rollup/plugin-json": "^6.0.0",
+		"@rollup/plugin-node-resolve": "^15.1.0",
 		"@types/minimist": "^1.2.2",
+		"ava": "^5.3.1",
 		"camelcase-keys": "^8.0.2",
+		"common-tags": "^1.8.2",
 		"decamelize": "^6.0.0",
 		"decamelize-keys": "^2.0.1",
+		"execa": "^7.2.0",
 		"hard-rejection": "^2.1.0",
+		"indent-string": "^5.0.0",
 		"minimist-options": "4.1.0",
 		"normalize-package-data": "^5.0.0",
+		"read-pkg": "^8.0.0",
 		"read-pkg-up": "^9.1.0",
 		"redent": "^4.0.0",
+		"rollup": "^3.27.0",
+		"rollup-plugin-license": "^3.0.1",
+		"strip-comments": "^2.0.1",
 		"trim-newlines": "^5.0.0",
+		"tsd": "^0.28.1",
 		"type-fest": "^3.9.0",
+		"xo": "^0.55.0",
 		"yargs-parser": "^21.1.1"
 	},
-	"devDependencies": {
-		"ava": "^5.2.0",
-		"common-tags": "^1.8.2",
-		"execa": "^7.1.1",
-		"indent-string": "^5.0.0",
-		"read-pkg": "^8.0.0",
-		"tsd": "^0.28.1",
-		"xo": "^0.54.2"
-	},
 	"xo": {
 		"rules": {
 			"unicorn/no-process-exit": "off",
 			"unicorn/error-message": "off"
-		}
+		},
+		"ignores": [
+			"build"
+		]
 	},
 	"ava": {
 		"files": [
-			"test/*"
+			"test/*",
+			"!test/build.js"
 		]
 	}
 }

rollup.config.js

@@ -0,0 +1,51 @@
+import json from '@rollup/plugin-json';
+import commonjs from '@rollup/plugin-commonjs';
+import {nodeResolve} from '@rollup/plugin-node-resolve';
+import license from 'rollup-plugin-license';
+/// import strip from 'strip-comments';
+import {defineConfig} from 'rollup';
+
+const outputDirectory = 'build';
+
+export default defineConfig({
+	input: [
+		'source/index.js',
+		'source/options.js',
+		'source/parser.js',
+		'source/utils.js',
+		'source/validate.js',
+	],
+	output: {
+		dir: outputDirectory,
+		interop: 'esModule',
+		generatedCode: {
+			preset: 'es2015',
+		},
+		chunkFileNames: '[name].js',
+		manualChunks(id) {
+			if (id.includes('node_modules')) {
+				return 'dependencies';
+			}
+		},
+		// TODO: strip deletes `https://...`
+		// plugins: [{
+		// 	name: 'strip-dependency-comments',
+		// 	renderChunk(code, chunk) {
+		// 		return chunk.name === 'dependencies' ? strip(code) : null;
+		// 	},
+		// }],
+	},
+	preserveEntrySignatures: 'allow-extension',
+	plugins: [
+		nodeResolve(),
+		commonjs({
+			include: 'node_modules/**',
+		}),
+		json(),
+		license({
+			thirdParty: {
+				output: `${outputDirectory}/licenses.md`,
+			},
+		}),
+	],
+});

test/build.js

@@ -0,0 +1,40 @@
+/* eslint-disable ava/no-ignored-test-files */
+import test from 'ava';
+import {readPackage} from 'read-pkg';
+import meow from '../build/index.js';
+import {spawnFixture} from './_utils.js';
+
+test('main', t => {
+	const cli = meow(`
+		Usage
+		  foo <input>
+	`, {
+		importMeta: import.meta,
+		argv: 'foo --foo-bar --u cat -- unicorn cake'.split(' '),
+		flags: {
+			unicorn: {shortFlag: 'u'},
+			meow: {default: 'dog'},
+			'--': true,
+		},
+	});
+
+	t.like(cli, {
+		input: ['foo'],
+		flags: {
+			fooBar: true,
+			meow: 'dog',
+			unicorn: 'cat',
+			'--': ['unicorn', 'cake'],
+		},
+		pkg: {
+			name: 'meow',
+		},
+		help: '\n  CLI app helper\n\n  Usage\n    foo <input>\n',
+	});
+});
+
+test('spawn cli and show version', async t => {
+	const pkg = await readPackage();
+	const {stdout} = await spawnFixture(['--version']);
+	t.is(stdout, pkg.version);
+});

test/fixtures/build.js

@@ -0,0 +1,26 @@
+#!/usr/bin/env node
+import process from 'node:process';
+import meow from '../../build/index.js';
+
+const cli = meow(`
+	Usage
+	  foo <input>
+`, {
+	importMeta: import.meta,
+	description: 'Custom description',
+	autoVersion: !process.argv.includes('--no-auto-version'),
+	autoHelp: !process.argv.includes('--no-auto-help'),
+	flags: {
+		unicorn: {shortFlag: 'u'},
+		meow: {default: 'dog'},
+		camelCaseOption: {default: 'foo'},
+	},
+});
+
+if (cli.flags.camelCaseOption === 'foo') {
+	for (const x of Object.keys(cli.flags)) {
+		console.log(x);
+	}
+} else {
+	console.log(cli.flags.camelCaseOption);
+}