index.js

/**
 * MockConsole class used to manage the 'console' built-in methods (ex log, info, error)
 */
export class MockConsole {
  constructor () {
    const proto = Object.getPrototypeOf(this)
    if (!proto.instance) {
      this.log = console.log
      this.info = console.info
      this.error = console.error
      this.logs = []
      this.infos = []
      this.errors = []
      proto.instance = this
    }
    return proto.instance
  }

  /**
   * Disable the console built-in methods
   */
  disable () {
    console.log = () => {}
    console.info = () => {}
    console.error = () => {}
  }

  /**
   * Capture the output of the console built-ins
   */
  capture () {
    console.log = log => { this.logs.push(log) }
    console.info = info => { this.infos.push(info) }
    console.error = err => { this.errors.push(err) }
  }

  /**
   * Restore the built-in console methods
   */
  restore () {
    console.log = this.log
    console.info = this.info
    console.error = this.error
  }

  /**
   * Flush the captured console output
   */
  flush () {
    this.logs = []
    this.infos = []
    this.errors = []
  }
}