app/assets/javascripts/admin/user_picker.js in spree_promo-1.3.2 vs app/assets/javascripts/admin/user_picker.js in spree_promo-1.3.3

@@ -1,30 +1,32 @@
 $.fn.userAutocomplete = function() {
-  this.select2({
-    minimumInputLength: 1,
-    multiple: true,
-    initSelection: function(element, callback) {
-      $.get(Spree.routes.user_search, { ids: element.val() }, function(data) { 
-        callback(data)
-      })
-    },
-    ajax: {
-      url: Spree.routes.user_search,
-      datatype: 'json',
-      data: function(term, page) {
-        return { q: term }
+  if (Spree.routes) {
+    this.select2({
+      minimumInputLength: 1,
+      multiple: true,
+      initSelection: function(element, callback) {
+        $.get(Spree.routes.user_search, { ids: element.val() }, function(data) { 
+          callback(data)
+        })
       },
-      results: function(data, page) {
-        return { results: data }
+      ajax: {
+        url: Spree.routes.user_search,
+        datatype: 'json',
+        data: function(term, page) {
+          return { q: term }
+        },
+        results: function(data, page) {
+          return { results: data }
+        }
+      },
+      formatResult: function(user) {
+        return user.email;
+      },
+      formatSelection: function(user) {
+        return user.email;
       }
-    },
-    formatResult: function(user) {
-      return user.email;
-    },
-    formatSelection: function(user) {
-      return user.email;
-    }
-  });
+    });
+  }
 }
 
 $(document).ready(function () {
   $('.user_picker').userAutocomplete();
 })