fixup: callback affiliation for multiple TokenRequest

lib/token-cache.js

@@ -53,19 +53,19 @@ TokenCache.prototype.authenticate = require('./auth').authenticate;
  */
 function TokenRequest(authenticate, options) {
 
-	var self = this;
 	this.status = 'expired';
 	this.pendingCallbacks = [];
 
 	// execute accumulated callbacks during the 'pending' state
-	function fireCallbacks(err, token) {
-		self.pendingCallbacks.forEach(function (callback) {
+	TokenRequest.prototype.fireCallbacks = function (err, token) {
+		this.pendingCallbacks.forEach(function (callback) {
 			callback(err, token);
 		});
-		self.pendingCallbacks = [];
+		this.pendingCallbacks = [];
 	}
 
 	TokenRequest.prototype.get = function (callback) {
+		var self = this;
 
 		if (self.status == 'expired') {
 
@@ -75,13 +75,13 @@ function TokenRequest(authenticate, options) {
 			authenticate(options, function (err, token) {
 				if (err) {
 					self.status = 'expired';
-					return fireCallbacks(err, null);
+					return self.fireCallbacks(err, null);
 				}
 				self.issued = Date.now();
 				self.duration = options.expiration || 60 * 60 * 1000;
 				self.token = token;
 				self.status = 'completed';
-				return fireCallbacks(null, token);
+				return self.fireCallbacks(null, token);
 			});
 
 		} else if (self.status == 'pending') {