Unknown Object in Custom Static Datasource


I created a custom Maniphest multi-value field wherein I’m using a static map as datasource. I was able to properly save and load the values from storage. However, when I’m going to update the field it shows Unknown Object (???), see screenshot below.


public function buildResults()
        $results = array();
        $bugTypes = [
          'functionality' => 'Functionality',
          'ui' => 'UI',
          'bad_ux' => 'Bad UX',
          'browser_compatibility' => 'Browser Compatibility',
          'localization' => 'Localization',
          'error_handling' => 'Error Handling',
          'performance' => 'Performance'

        foreach ($bugTypes as $key => $value) {
            $result = id(new PhabricatorTypeaheadResult())
            $results[] = $result;
        return $results;


public function renderEditControl(array $handles)
        $value = $this->getFieldValue();
        $control = id(new AphrontFormTokenizerControl())
        ->setValue(nonempty($value, array()));

        return $control;