The class Drupal\conditional_fields\Form\ConditionalFieldForm extends FormBase and has a method submitForm() which calls the parent::submitForm, but the parent class is abstract so this is not permitted.
public function submitForm(array &$form, FormStateInterface $form_state) {
$table = $form_state->getValue('table');
if (empty($table['add_new_dependency']) || !is_array($table['add_new_dependency'])) {
parent::submitForm($form, $form_state);
}
Not sure what is expected to happen when the if statement returns a TRUE value, but as nothing will actually happen, the whole if statement should probably be removed.
Note also that there are two calls to "parent::validateForm() which exists but is an empty function, so these calls should probably also be removed as they achieve nothing.
Needs review
4.0
Code
Hi @jlscott,
I have fixed this issue and also created MR for this. kindly review the changes.