How to use

_isEqual

function

in

lodash

/**
  * Fetch the ID of a channel matched by type and channel data filter
  *
  * @param {string} type - channel type
  * @param {object} filter - to be matched against channel data
  * @returns {number} channelID
  */
 getDataChannelId (type, filter) {
  return Object
   .keys(this._channelMap)
   .find(cid => {
    const c = this._channelMap[cid]
    const fv = _pick(c, Object.keys(filter))
    return c.channel === type && _isEqual(fv, filter)
   })
 }

/**
  * Returns the first socket that is subscribed/pending sub to the specified
  * channel.
  *
  * @param {string} type - i.e. 'book'
  * @param {object} filter - i.e. { symbol: 'tBTCUSD', prec: 'R0' }
  * @returns {object} wsState - undefined if not found
  */
 getSocketWithDataChannel (type, filter) {
  return this._sockets.find(s => {
   const subI = s.pendingSubscriptions.findIndex(s => (
    s[0] === type && _isEqual(s[1], filter)
   ))

   if (subI !== -1) {
    return true
   }

   // Confirm unsub is not pending
   const cid = s.ws.getDataChannelId(type, filter)

   if (!cid) {
    return false
   }

   return cid && !_includes(s.pendingUnsubscriptions, cid)
  })
 }

_isEqual(fv, sub[1])