Allow for number user ids

Author: blazzy

amplitude.js

@@ -5730,7 +5730,7 @@ AmplitudeClient.prototype.init = function init(apiKey, opt_userId, opt_config, o
 
     // load deviceId and userId from input, or try to fetch existing value from cookie
     this.options.deviceId = type(opt_config) === 'object' && type(opt_config.deviceId) === 'string' && !utils.isEmptyString(opt_config.deviceId) && opt_config.deviceId || this.options.deviceIdFromUrlParam && this._getDeviceIdFromUrlParam(this._getUrlParams()) || this.options.deviceId || uuid$1() + 'R';
-    this.options.userId = type(opt_userId) === 'string' && !utils.isEmptyString(opt_userId) && opt_userId || this.options.userId || null;
+    this.options.userId = type(opt_userId) === 'string' && !utils.isEmptyString(opt_userId) && opt_userId || type(opt_userId) === 'number' && opt_userId.toString() || this.options.userId || null;
 
     // load unsent events and identifies before any attempt to log new ones
     if (this.options.saveEvents) {

amplitude.min.js

@@ -83,7 +83,9 @@ AmplitudeClient.prototype.init = function init(apiKey, opt_userId, opt_config, o
         !utils.isEmptyString(opt_config.deviceId) && opt_config.deviceId) ||
         (this.options.deviceIdFromUrlParam && this._getDeviceIdFromUrlParam(this._getUrlParams())) ||
         this.options.deviceId || UUID() + 'R';
-    this.options.userId = (type(opt_userId) === 'string' && !utils.isEmptyString(opt_userId) && opt_userId) ||
+    this.options.userId =
+      (type(opt_userId) === 'string' && !utils.isEmptyString(opt_userId) && opt_userId) ||
+      (type(opt_userId) === 'number' && opt_userId.toString()) ||
         this.options.userId || null;
 
     // load unsent events and identifies before any attempt to log new ones

src/amplitude-client.js

@@ -73,6 +73,12 @@ describe('AmplitudeClient', function() {
       assert.equal(amplitude.options.userId, userId);
     });
 
+    it('should accept numerical userIds', function() {
+      const userId = 5;
+      amplitude.init(apiKey, 5);
+      assert.equal(amplitude.options.userId, '5');
+    });
+
     it('should generate a random deviceId', function() {
       amplitude.init(apiKey, userId);
       assert.lengthOf(amplitude.options.deviceId, 37); // UUID is length 36, but we append 'R' at end