fix(JitsiParticipant): compare against specific error constant

JitsiParticipant.js

@@ -6,6 +6,7 @@ import { getLogger } from 'jitsi-meet-logger';
 import * as JitsiConferenceEvents from './JitsiConferenceEvents';
 import { ParticipantConnectionStatus }
     from './modules/connectivity/ParticipantConnectionStatus';
+import { ERROR_FEATURE_VERSION_MISMATCH } from './modules/xmpp/Caps';
 import * as MediaType from './service/RTC/MediaType';
 
 const logger = getLogger(__filename);
@@ -246,11 +247,8 @@ export default class JitsiParticipant {
 
         this._getFeaturesPromise = this._conference.xmpp.caps.getFeatures(this._jid, timeout)
             .catch(error => {
-                // FIXME there's a risk of getting into an endless loop should anything along the way decide to reject
-                //  with a string. Compare against a specific string instead.
-                // when we detect version mismatch we return a string as error
-                // we want to retry in such case
-                if (error && error.constructor === String) {
+                // Retry on feature version mismatch
+                if (error === ERROR_FEATURE_VERSION_MISMATCH) {
                     return this._conference.xmpp.caps.getFeatures(this._jid, timeout);
                 }
 

modules/xmpp/Caps.js

@@ -14,6 +14,8 @@ const IDENTITY_PROPERTIES = [ 'category', 'type', 'lang', 'name' ];
 const IDENTITY_PROPERTIES_FOR_COMPARE = [ 'category', 'type', 'lang' ];
 const HASH = 'sha-1';
 
+export const ERROR_FEATURE_VERSION_MISMATCH = 'Feature version mismatch';
+
 /**
  *
  * @param a
@@ -167,7 +169,7 @@ export default class Caps extends Listenable {
                         logger.error(`Expected node ${node} but received ${
                             receivedNode}`);
 
-                        return Promise.reject('Feature version mismatch');
+                        return Promise.reject(ERROR_FEATURE_VERSION_MISMATCH);
                     }
                 });
         }