Reset EventEmitter2

output.txt

> node test.js

Start test
  Catch!
end


Start test
  Catch!
  Catch!
end


Start test
  Catch!
  Catch!
  Catch!
end

test.js

const {EventEmitter2} = require('eventemitter2')

let bus 
bus = new EventEmitter2()

function reset_1() {
  // fail !
  bus.offAny()
}

function reset_2() {
  bus._all = []
  bus._events = {}
}

function reset_3() {
  // WARNING
  
  // this solves the test problem, but also breaks code which makes a copy of your bus.
  //
  // If you pass around instances of your bus, it is very likely you will break something
  // if you just replace it with a new one
  bus = new EventEmitter2()
}


function test() {
  console.log('Start test')
  // reset_1()

  // WARNING
  // 
  // You might be tempted to just test your code with 'once'. This however has two problems:
  //   1. You will not notice unexpected extra calls
  //   2. The code subscribing is out of your test, and it must always listen
  bus.on('my-signal', () => {
    console.log('  Catch!')
  })

  bus.emit('my-signal', 'hello')

  console.log('end')
  console.log()
  console.log()
}

test()
test()
test()

Note to self: I've changed my mind

reset_3 might be the best solution after all. Currently reset_2 will break code which already subscribed to the previous bus. If you must reset your bus you also must reset objects depending on it. You might consider this type of reset:

bus.onAny( e => {
  throw Error('You are using an old instance of your bus')
})
bus = new EventEmitter2()

Notice that this will not solve your problems, it will just expose a lifecycle problem in your current code.