chalk/index.js

'use strict';
const escapeStringRegexp = require('escape-string-regexp');
const ansiStyles = require('ansi-styles');
const {stdout: stdoutColor} = require('supports-color');
const template = require('./templates.js');

const isSimpleWindowsTerm = process.platform === 'win32' && !(process.env.TERM || '').toLowerCase().startsWith('xterm');

// `supportsColor.level` → `ansiStyles.color[name]` mapping
const levelMapping = ['ansi', 'ansi', 'ansi256', 'ansi16m'];

// `color-convert` models to exclude from the Chalk API due to conflicts and such
const skipModels = new Set(['gray']);

const styles = Object.create(null);

function applyOptions(object, options = {}) {
	if (options.level > 3 || options.level < 0) {
		throw new Error('The `level` option should be an integer from 0 to 3');
	}

	// Detect level if not set manually
	const colorLevel = stdoutColor ? stdoutColor.level : 0;
	object.level = options.level === undefined ? colorLevel : options.level;
	object.enabled = 'enabled' in options ? options.enabled : object.level > 0;
}

function Chalk(options) {
	// We check for this.template here since calling `chalk.constructor()`
	// by itself will have a `this` of a previously constructed chalk object
	if (!this || !(this instanceof Chalk) || this.template) {
		const chalk = {};
		applyOptions(chalk, options);

		chalk.template = (...args) => chalkTag(chalk.template, ...args);

		Object.setPrototypeOf(chalk, Chalk.prototype);
		Object.setPrototypeOf(chalk.template, chalk);

		chalk.template.constructor = Chalk;

		return chalk.template;
	}

	applyOptions(this, options);
}

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

	styles[key] = {
		get() {
			const codes = ansiStyles[key];
			return build.call(this, [...(this._styles || []), codes], this._empty, key);
		}
	};
}

styles.visible = {
	get() {
		return build.call(this, this._styles || [], true, 'visible');
	}
};

ansiStyles.color.closeRe = new RegExp(escapeStringRegexp(ansiStyles.color.close), 'g');
for (const model of Object.keys(ansiStyles.color.ansi)) {
	if (skipModels.has(model)) {
		continue;
	}

	styles[model] = {
		get() {
			const {level} = this;
			return function (...args) {
				const open = ansiStyles.color[levelMapping[level]][model](...args);
				const codes = {
					open,
					close: ansiStyles.color.close,
					closeRe: ansiStyles.color.closeRe
				};
				return build.call(this, [...(this._styles || []), codes], this._empty, model);
			};
		}
	};
}

ansiStyles.bgColor.closeRe = new RegExp(escapeStringRegexp(ansiStyles.bgColor.close), 'g');
for (const model of Object.keys(ansiStyles.bgColor.ansi)) {
	if (skipModels.has(model)) {
		continue;
	}

	const bgModel = 'bg' + model[0].toUpperCase() + model.slice(1);
	styles[bgModel] = {
		get() {
			const {level} = this;
			return function (...args) {
				const open = ansiStyles.bgColor[levelMapping[level]][model](...args);
				const codes = {
					open,
					close: ansiStyles.bgColor.close,
					closeRe: ansiStyles.bgColor.closeRe
				};
				return build.call(this, [...(this._styles || []), codes], this._empty, model);
			};
		}
	};
}

const proto = Object.defineProperties(() => {}, styles);

function build(_styles, _empty, key) {
	const builder = (...args) => applyStyle.call(builder, ...args);
	builder._styles = _styles;
	builder._empty = _empty;

	const self = this;

	Object.defineProperty(builder, 'level', {
		enumerable: true,
		get() {
			return self.level;
		},
		set(level) {
			self.level = level;
		}
	});

	Object.defineProperty(builder, 'enabled', {
		enumerable: true,
		get() {
			return self.enabled;
		},
		set(enabled) {
			self.enabled = enabled;
		}
	});

	// See below for fix regarding invisible grey/dim combination on Windows
	builder.hasGrey = this.hasGrey || key === 'gray' || key === 'grey';

	// `__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; // eslint-disable-line no-proto

	return builder;
}

function applyStyle(...args) {
	let string = args.join(' ');

	if (!this.enabled || this.level <= 0 || !string) {
		return this._empty ? '' : string;
	}

	// Turns out that on Windows dimmed gray text becomes invisible in cmd.exe,
	// see https://github.com/chalk/chalk/issues/58
	// If we're on Windows and we're dealing with a gray color, temporarily make 'dim' a noop.
	const originalDim = ansiStyles.dim.open;
	if (isSimpleWindowsTerm && this.hasGrey) {
		ansiStyles.dim.open = '';
	}

	for (const code of this._styles.slice().reverse()) {
		// 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'.
		string = code.open + string.replace(code.closeRe, code.open) + code.close;

		// Close the styling before a linebreak and reopen
		// after next line to fix a bleed issue on macOS
		// https://github.com/chalk/chalk/pull/92
		string = string.replace(/\r?\n/g, `${code.close}$&${code.open}`);
	}

	// Reset the original `dim` if we changed it to work around the Windows dimmed gray issue
	ansiStyles.dim.open = originalDim;

	return string;
}

function chalkTag(chalk, ...strings) {
	const [firstString] = strings;

	if (!Array.isArray(firstString)) {
		// If chalk() was called by itself or with a string,
		// return the string itself as a string.
		return strings.join(' ');
	}

	const args = strings.slice(1);
	const parts = [firstString.raw[0]];

	for (let i = 1; i < firstString.length; i++) {
		parts.push(
			String(args[i - 1]).replace(/[{}\\]/g, '\\$&'),
			String(firstString.raw[i])
		);
	}

	return template(chalk, parts.join(''));
}

Object.defineProperties(Chalk.prototype, styles);

module.exports = Chalk(); // eslint-disable-line new-cap
module.exports.supportsColor = stdoutColor;
module.exports.default = module.exports; // For TypeScript