chalk/index.js

'use strict';
var escapeStringRegexp = require('escape-string-regexp');
var ansiStyles = require('ansi-styles');
var stripAnsi = require('strip-ansi');
var hasAnsi = require('has-ansi');
var supportsColor = require('supports-color');
var defineProps = Object.defineProperties;

function Chalk(options) {
	// detect mode if not set manually
	this.enabled = !options || options.enabled === undefined ? supportsColor : options.enabled;
}

// use bright blue on Windows as the normal blue color is illegible
if (process.platform === 'win32' && !/^xterm/i.test(process.env.TERM || '')) {
	ansiStyles.blue.open = '\u001b[94m';
}

function build(_styles) {
	var builder = function builder() {
		return applyStyle.apply(builder, arguments);
	};
	builder._styles = _styles;
	builder.enabled = this.enabled;
	// __proto__ is used because we must return a function, but there is
	// no way to create a function with a different prototype.
	builder.__proto__ = proto;
	return builder;
}

var styles = (function () {
	var ret = {};

	Object.keys(ansiStyles).forEach(function (key) {
		ansiStyles[key].closeRe = new RegExp(escapeStringRegexp(ansiStyles[key].close), 'g');

		ret[key] = {
			get: function () {
				return build.call(this, this._styles.concat(key));
			}
		};
	});

	return ret;
})();

var proto = defineProps(function chalk() {}, styles);

function applyStyle() {
	// support varags, but simply cast to string in case there's only one arg
	var args = arguments;
	var argsLen = args.length;
	var str = argsLen !== 0 && String(arguments[0]);
	if (argsLen > 1) {
		// don't slice `arguments`, it prevents v8 optimizations
		for (var a = 1; a < argsLen; a++) {
			str += ' ' + args[a];
		}
	}

	if (!this.enabled || !str) {
		return str;
	}

	/*jshint validthis: true */
	var nestedStyles = this._styles;

	var i = nestedStyles.length;
	while (i--) {
		var code = ansiStyles[nestedStyles[i]];
		// Replace any instances already present with a re-opening code
		// otherwise only the part of the string until said closing code
		// will be colored, and the rest will simply be 'plain'.
		str = code.open + str.replace(code.closeRe, code.open) + code.close;
	}

	return str;
}

function init() {
	var ret = {};

	Object.keys(styles).forEach(function (name) {
		ret[name] = {
			get: function () {
				return build.call(this, [name]);
			}
		};
	});

	return ret;
}

defineProps(Chalk.prototype, init());

module.exports = new Chalk();
module.exports.styles = ansiStyles;
module.exports.hasColor = hasAnsi;
module.exports.stripColor = stripAnsi;
module.exports.supportsColor = supportsColor;