haul/src/logger.js

/**
 * Copyright 2017-present, Callstack.
 * All rights reserved.
 *
 * @flow
 */
import type { Logger } from './types';

const chalk = require('chalk');
const stripAnsi = require('strip-ansi');

let lastChar;

const last = arr => arr[arr.length - 1];

const section = (...args) => {
  if (lastChar !== '\n') {
    console.log();
  }
  log(...args);
};

const log = (...args) => {
  lastChar = last(stripAnsi(last(args)));
  console.log(...args);
};

function reset() {
  const logger = {
    info: (...args: any[]) => section(chalk.black.bgCyan(' INFO '), ...args),
    warn: (...args: any[]) => section(chalk.black.bgYellow(' WARN '), ...args),
    error: (...args: any[]) => section(chalk.black.bgRed(' ERROR '), ...args),
    done: (...args: any[]) => section(chalk.black.bgGreen(' DONE '), ...args),
    debug: (prefix: string, ...args: any[]) =>
      log(
        chalk.cyan(prefix.toUpperCase()),
        ...args.map(str => chalk.grey(str))
      ),
    reset,
  };

  Object.defineProperty(logger, 'reset', {
    ...Object.getOwnPropertyDescriptor(logger, 'reset').value,
    writable: false,
  });

  return logger;
}

const logger: Logger = reset();

module.exports = logger;