diff --git a/tests/js/encryption-tests.js b/tests/js/encryption-tests.js
index 14926b5e..f8c9f68c 100644
--- a/tests/js/encryption-tests.js
+++ b/tests/js/encryption-tests.js
@@ -69,24 +69,21 @@ module.exports = {
             Realm.schemaVersion('encrypted.realm', 'asdf');
         });
     },
-};
 
+    testEncryptionWithSync: function() {
+        if (!global.enableSyncTests) {
+            return Promise.resolve();
+        }
 
-if (global.enableSyncTests) {
-    module.exports.testEncryptionWithSync = function() {
-        Realm.Sync.User.login('http://localhost:9080', global.testAdminUserInfo.username, global.testAdminUserInfo.password, (error, user) => {
-            if (error) {
-                reject(error);
-            }
+        return Realm.Sync.User.login('http://localhost:9080', "realm-admin", '').then(adminUser => { 
             new Realm({
                 encryptionKey: new Int8Array(64),
                 sync: {
-                    user: user,
+                    user: adminUser,
                     url: 'realm://localhost:9080'
                 }
             });
-            user.logout(); // FIXME: clearTestState() doesn't clean up enough and Realm.Sync.User.current might not work
-            resolve();
+            adminUser.logout(); // FIXME: clearTestState() doesn't clean up enough and Realm.Sync.User.current might not work
         });
     }
-}
+};
diff --git a/tests/js/index.js b/tests/js/index.js
index 06d4be55..b0f57f5c 100644
--- a/tests/js/index.js
+++ b/tests/js/index.js
@@ -20,7 +20,11 @@
 
 const Realm = require('realm');
 
-global.enableSyncTests = Realm.Sync;
+
+if( typeof Realm.Sync !== 'undefined' && Realm.Sync !== null ) {
+    global.WARNING = "global is not available in React Native. Use it only in tests";
+    global.enableSyncTests = true;
+}
 
 const isNodeProcess = typeof process === 'object' && process + '' === '[object process]';
 function node_require(module) { return require(module); }