text:  const users = []
  
   const addUser = ({id, name, room}) => {
      const numberOfUsersInRoom = users.filter(user => user.room === room).length
      if(numberOfUsersInRoom === 2)
      return { error: 'Room full' }
  
      const newUser = { id, name, room }
      users.push(newUser)
      return { newUser }
  }
  
  const removeUser = id => {
      const removeIndex = users.findIndex(user => user.id === id)
  
      if(removeIndex!==-1)
          return users.splice(removeIndex, 1)[0]
  }
  
  const getUser = id => {
      return users.find(user => user.id === id)
  }
  
  const getUsersInRoom = room => {
      return users.filter(user => user.room === room)
  }
  
  module.exports = { addUser, removeUser, getUser, getUsersInRoom }