Console.js

/**
 * Copyright (c) 2014-present, Facebook, Inc. All rights reserved.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 *
 * @flow
 */
/* global stream$Writable */

import type {LogType, LogMessage} from 'types/Console';

import {format} from 'util';
import {Console} from 'console';
import clearLine from './clear_line';

type Formatter = (type: LogType, message: LogMessage) => string;

export default class CustomConsole extends Console {
  _stdout: stream$Writable;
  _formatBuffer: Formatter;

  constructor(
    stdout: stream$Writable,
    stderr: stream$Writable,
    formatBuffer: ?Formatter,
  ) {
    super(stdout, stderr);
    this._formatBuffer = formatBuffer || ((type, message) => message);
  }

  _log(type: LogType, message: string) {
    clearLine(this._stdout);
    super.log(this._formatBuffer(type, message));
  }

  debug(...args: Array<mixed>) {
    this._log('debug', format.apply(null, arguments));
  }

  log(...args: Array<mixed>) {
    this._log('log', format.apply(null, arguments));
  }

  info(...args: Array<mixed>) {
    this._log('info', format.apply(null, arguments));
  }

  warn(...args: Array<mixed>) {
    this._log('warn', format.apply(null, arguments));
  }

  error(...args: Array<mixed>) {
    this._log('error', format.apply(null, arguments));
  }

  getBuffer() {
    return null;
  }
}