Require Node.js 14 and move to ESM

Closes #83

Author: sindresorhus

.github/workflows/main.yml

@@ -13,8 +13,6 @@ jobs:
           - 18
           - 16
           - 14
-          - 12
-          - 10
     steps:
       - uses: actions/checkout@v3
       - uses: actions/setup-node@v3

index.d.ts

@@ -1,43 +1,44 @@
-declare namespace camelcase {
-	interface Options {
-		/**
-		Uppercase the first character: `foo-bar` → `FooBar`.
-
-		@default false
-		*/
-		readonly pascalCase?: boolean;
-
-		/**
-		Preserve the consecutive uppercase characters: `foo-BAR` → `FooBAR`.
-
-		@default false
-		*/
-		readonly preserveConsecutiveUppercase?: boolean;
-
-		/**
-		The locale parameter indicates the locale to be used to convert to upper/lower case according to any locale-specific case mappings. If multiple locales are given in an array, the best available locale is used.
-
-		Setting `locale: false` ignores the platform locale and uses the [Unicode Default Case Conversion](https://unicode-org.github.io/icu/userguide/transforms/casemappings.html#simple-single-character-case-mapping) algorithm.
-
-		Default: The host environment’s current locale.
-
-		@example
-		```
-		import camelCase = require('camelcase');
-
-		camelCase('lorem-ipsum', {locale: 'en-US'});
-		//=> 'loremIpsum'
-		camelCase('lorem-ipsum', {locale: 'tr-TR'});
-		//=> 'loremİpsum'
-		camelCase('lorem-ipsum', {locale: ['en-US', 'en-GB']});
-		//=> 'loremIpsum'
-		camelCase('lorem-ipsum', {locale: ['tr', 'TR', 'tr-TR']});
-		//=> 'loremİpsum'
-		```
-		*/
-		readonly locale?: false | string | readonly string[];
-	}
-}
+export type Options = {
+	/**
+	Uppercase the first character: `foo-bar` → `FooBar`.
+
+	@default false
+	*/
+	readonly pascalCase?: boolean;
+
+	/**
+	Preserve consecutive uppercase characters: `foo-BAR` → `FooBAR`.
+
+	@default false
+	*/
+	readonly preserveConsecutiveUppercase?: boolean;
+
+	/**
+	The locale parameter indicates the locale to be used to convert to upper/lower case according to any locale-specific case mappings. If multiple locales are given in an array, the best available locale is used.
+
+	Setting `locale: false` ignores the platform locale and uses the [Unicode Default Case Conversion](https://unicode-org.github.io/icu/userguide/transforms/casemappings.html#simple-single-character-case-mapping) algorithm.
+
+	Default: The host environment’s current locale.
+
+	@example
+	```
+	import camelCase from 'camelcase';
+
+	camelCase('lorem-ipsum', {locale: 'en-US'});
+	//=> 'loremIpsum'
+
+	camelCase('lorem-ipsum', {locale: 'tr-TR'});
+	//=> 'loremİpsum'
+
+	camelCase('lorem-ipsum', {locale: ['en-US', 'en-GB']});
+	//=> 'loremIpsum'
+
+	camelCase('lorem-ipsum', {locale: ['tr', 'TR', 'tr-TR']});
+	//=> 'loremİpsum'
+	```
+	*/
+	readonly locale?: false | string | readonly string[];
+};
 
 /**
 Convert a dash/dot/underscore/space separated string to camelCase or PascalCase: `foo-bar` → `fooBar`.
@@ -48,7 +49,7 @@ Correctly handles Unicode strings.
 
 @example
 ```
-import camelCase = require('camelcase');
+import camelCase from 'camelcase';
 
 camelCase('foo-bar');
 //=> 'fooBar'
@@ -95,9 +96,7 @@ camelCase('lorem-ipsum', {locale: 'en-US'});
 //=> 'loremIpsum'
 ```
 */
-declare function camelcase(
+export default function camelcase(
 	input: string | readonly string[],
-	options?: camelcase.Options
+	options?: Options
 ): string;
-
-export = camelcase;

index.js

@@ -1,5 +1,3 @@
-'use strict';
-
 const UPPERCASE = /[\p{Lu}]/u;
 const LOWERCASE = /[\p{Ll}]/u;
 const LEADING_CAPITAL = /^[\p{Lu}](?![\p{Lu}])/gu;
@@ -15,17 +13,17 @@ const preserveCamelCase = (string, toLowerCase, toUpperCase) => {
 	let isLastCharUpper = false;
 	let isLastLastCharUpper = false;
 
-	for (let i = 0; i < string.length; i++) {
-		const character = string[i];
+	for (let index = 0; index < string.length; index++) {
+		const character = string[index];
 
 		if (isLastCharLower && UPPERCASE.test(character)) {
-			string = string.slice(0, i) + '-' + string.slice(i);
+			string = string.slice(0, index) + '-' + string.slice(index);
 			isLastCharLower = false;
 			isLastLastCharUpper = isLastCharUpper;
 			isLastCharUpper = true;
-			i++;
+			index++;
 		} else if (isLastCharUpper && isLastLastCharUpper && LOWERCASE.test(character)) {
-			string = string.slice(0, i - 1) + '-' + string.slice(i - 1);
+			string = string.slice(0, index - 1) + '-' + string.slice(index - 1);
 			isLastLastCharUpper = isLastCharUpper;
 			isLastCharUpper = false;
 			isLastCharLower = true;
@@ -53,15 +51,15 @@ const postProcess = (input, toUpperCase) => {
 		.replace(NUMBERS_AND_IDENTIFIER, m => toUpperCase(m));
 };
 
-const camelCase = (input, options) => {
+export default function camelCase(input, options) {
 	if (!(typeof input === 'string' || Array.isArray(input))) {
 		throw new TypeError('Expected the input to be `string | string[]`');
 	}
 
 	options = {
 		pascalCase: false,
 		preserveConsecutiveUppercase: false,
-		...options
+		...options,
 	};
 
 	if (Array.isArray(input)) {
@@ -76,12 +74,13 @@ const camelCase = (input, options) => {
 		return '';
 	}
 
-	const toLowerCase = options.locale === false ?
-		string => string.toLowerCase() :
-		string => string.toLocaleLowerCase(options.locale);
-	const toUpperCase = options.locale === false ?
-		string => string.toUpperCase() :
-		string => string.toLocaleUpperCase(options.locale);
+	const toLowerCase = options.locale === false
+		? string => string.toLowerCase()
+		: string => string.toLocaleLowerCase(options.locale);
+
+	const toUpperCase = options.locale === false
+		? string => string.toUpperCase()
+		: string => string.toLocaleUpperCase(options.locale);
 
 	if (input.length === 1) {
 		if (SEPARATORS.test(input)) {
@@ -98,20 +97,11 @@ const camelCase = (input, options) => {
 	}
 
 	input = input.replace(LEADING_SEPARATORS, '');
-
-	if (options.preserveConsecutiveUppercase) {
-		input = preserveConsecutiveUppercase(input, toLowerCase);
-	} else {
-		input = toLowerCase(input);
-	}
+	input = options.preserveConsecutiveUppercase ? preserveConsecutiveUppercase(input, toLowerCase) : toLowerCase(input);
 
 	if (options.pascalCase) {
 		input = toUpperCase(input.charAt(0)) + input.slice(1);
 	}
 
 	return postProcess(input, toUpperCase);
-};
-
-module.exports = camelCase;
-// TODO: Remove this for the next major release
-module.exports.default = camelCase;
+}

index.test-d.ts

@@ -1,5 +1,5 @@
 import {expectType} from 'tsd';
-import camelCase = require('.');
+import camelCase from './index.js';
 
 expectType<string>(camelCase('foo-bar'));
 expectType<string>(camelCase('розовый_пушистый_единороги'));

package.json

@@ -10,8 +10,11 @@
 		"email": "sindresorhus@gmail.com",
 		"url": "https://sindresorhus.com"
 	},
+	"type": "module",
+	"exports": "./index.js",
+	"types": "./index.d.ts",
 	"engines": {
-		"node": ">=10"
+		"node": ">=14.16"
 	},
 	"scripts": {
 		"test": "xo && ava && tsd"
@@ -37,8 +40,8 @@
 		"pascal-case"
 	],
 	"devDependencies": {
-		"ava": "^1.4.1",
-		"tsd": "^0.11.0",
-		"xo": "^0.28.3"
+		"ava": "^4.3.0",
+		"tsd": "^0.20.0",
+		"xo": "^0.49.0"
 	}
 }

readme.md

@@ -8,16 +8,14 @@ If you use this on untrusted user input, don't forget to limit the length to som
 
 ## Install
 
+```sh
+npm install camelcase
 ```
-$ npm install camelcase
-```
-
-*If you need to support Firefox < 78, stay on version 5 as version 6 uses regex features not available in Firefox < 78.*
 
 ## Usage
 
 ```js
-const camelCase = require('camelcase');
+import camelCase from 'camelcase';
 
 camelCase('foo-bar');
 //=> 'fooBar'
@@ -90,7 +88,7 @@ Uppercase the first character: `foo-bar` → `FooBar`
 Type: `boolean`\
 Default: `false`
 
-Preserve the consecutive uppercase characters: `foo-BAR` → `FooBAR`.
+Preserve consecutive uppercase characters: `foo-BAR` → `FooBAR`.
 
 ##### locale
 
@@ -100,7 +98,7 @@ Default: The host environment’s current locale.
 The locale parameter indicates the locale to be used to convert to upper/lower case according to any locale-specific case mappings. If multiple locales are given in an array, the best available locale is used.
 
 ```js
-const camelCase = require('camelcase');
+import camelCase from 'camelcase';
 
 camelCase('lorem-ipsum', {locale: 'en-US'});
 //=> 'loremIpsum'
@@ -118,7 +116,7 @@ camelCase('lorem-ipsum', {locale: ['tr', 'TR', 'tr-TR']});
 Setting `locale: false` ignores the platform locale and uses the [Unicode Default Case Conversion](https://unicode-org.github.io/icu/userguide/transforms/casemappings.html#simple-single-character-case-mapping) algorithm:
 
 ```js
-const camelCase = require('camelcase');
+import camelCase from 'camelcase';
 
 // On a platform with 'tr-TR'
 

test.js

@@ -1,5 +1,5 @@
 import test from 'ava';
-import camelCase from '.';
+import camelCase from './index.js';
 
 test('camelCase', t => {
 	t.is(camelCase('foo'), 'foo');
@@ -228,7 +228,9 @@ test('camelCase with disabled locale', t => {
 test('invalid input', t => {
 	t.throws(() => {
 		camelCase(1);
-	}, /Expected the input to be/);
+	}, {
+		message: /Expected the input to be/,
+	});
 });
 
 /* eslint-disable no-extend-native */
@@ -242,11 +244,11 @@ const withLocaleCaseFunctionsMocked = fn => {
 
 	Object.defineProperty(String.prototype, 'toLocaleUpperCase', {
 		...toLocaleUpperCase,
-		value: throwWhenBeingCalled
+		value: throwWhenBeingCalled,
 	});
 	Object.defineProperty(String.prototype, 'toLocaleLowerCase', {
 		...toLocaleLowerCase,
-		value: throwWhenBeingCalled
+		value: throwWhenBeingCalled,
 	});
 
 	try {