Merge branch 'bugfix/put_data_no_empty_key' into 'master'

dont save empty keys

See merge request !4

changelog.txt

-= 1.0 - 2019-12-16 =
+# Changelog
+
+## 2.0.2 - 2020-06-17
+### Changed
+- Skip saving empty keys in the PersistentContainer
+
+## 2.0.1 - 2020-06-05
+### Changed
+- Stable version of persistent library is used
+
+## 2.0.0 - 2020-05-26
+### Changed
+- Whole library has been rewritten
+
+## 1.0 - 2019-12-16 =
 * First release

src/Form/FormWithFields.php

@@ -171,6 +171,11 @@ class FormWithFields implements Form, ContainerForm, FieldProvider {
 	public function put_data( PersistentContainer $container ) {
 		foreach ( $this->get_fields() as $field ) {
 			$data_key = $field->get_name();
+
+			if ( empty( $data_key ) ) {
+				continue;
+			}
+
 			if ( ! isset( $this->updated_data[ $data_key ] ) ) {
 				$container->set( $data_key, $field->get_default_value() );
 			} else {