handle undefined, add test

src/kibana/components/validate_query/lib/to_user.js

@@ -7,6 +7,7 @@ define(function (require) {
    * @returns {string}
    */
   return function (text) {
+    if (_.isUndefined(text)) return '';
     if (_.isString(text)) return text;
     if (_.isObject(text)) {
       if (text.query_string) return text.query_string.query;

test/unit/specs/directives/validate_query.js

@@ -182,6 +182,11 @@ define(function (require) {
     });
 
     describe('model presentation formatter', function () {
+      it('should present undefined as empty string', function () {
+        var notDefined;
+        expect(toUser(notDefined)).to.be('');
+      });
+
       it('should present objects as strings', function () {
         expect(toUser({foo: 'bar'})).to.be('{"foo":"bar"}');
       });