diff --git a/apps/files/tests/js/fileUploadSpec.js b/apps/files/tests/js/fileUploadSpec.js
index 81a0a2df61067d6030e3ff259b8ba85490d66961..6dde2734f1dd83d2713115aaca6302b1f3d40aa1 100644
--- a/apps/files/tests/js/fileUploadSpec.js
+++ b/apps/files/tests/js/fileUploadSpec.js
@@ -66,7 +66,7 @@ describe('OC.Upload tests', function() {
 				originalFiles: files,
 				files: [file],
 				jqXHR: jqXHR,
-				response: sinon.stub.returns(jqXHR),
+				response: sinon.stub().returns(jqXHR),
 				submit: sinon.stub()
 			};
 			if (uploader.fileUploadParam.add.call(