Field inheritance is working

recurring_events.module

@@ -43,8 +43,15 @@ function recurring_events_entity_base_field_info_alter(&$fields, EntityTypeInter
         if ($field->entityField()) {
           $settings['entity field'] = $field->entityField();
         }
-        // Get field definition to find field type.
-        $fields[$field->id()] = BaseFieldDefinition::create('string')
+
+        $field_definitions = \Drupal::service('entity_field.manager')->getFieldDefinitions('eventseries', 'eventseries');
+
+        $type = 'string';
+        if (!empty($field_definitions[$field->sourceField()])) {
+          $type = $field_definitions[$field->sourceField()]->getType();
+        }
+
+        $fields[$field->id()] = BaseFieldDefinition::create($type)
           ->setLabel($field->label())
           ->setName($field->id())
           ->setDescription(t('The inherited field: @field', ['@field' => $field->label()]))

src/Annotation/FieldInheritance.php

@@ -27,4 +27,11 @@ class FieldInheritance extends Plugin {
    */
   public $name;
 
+  /**
+   * An array of field types the inheritance plugin supports.
+   *
+   * @var array
+   */
+  public $types = [];
+
 }

src/Form/FieldInheritanceDeleteForm.php

@@ -47,6 +47,7 @@ class FieldInheritanceDeleteForm extends EntityConfirmFormBase {
         )
     );
 
+    \Drupal::service('entity_field.manager')->clearCachedFieldDefinitions();
     $form_state->setRedirectUrl($this->getCancelUrl());
   }
 

src/Form/FieldInheritanceForm.php

@@ -108,6 +108,44 @@ class FieldInheritanceForm extends EntityForm {
     return $form;
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function validateForm(array &$form, FormStateInterface $form_state) {
+    parent::validateForm($form, $form_state);
+    $values = $form_state->getValues();
+
+    if (!empty($values['sourceField']) && !empty($values['entityField'])) {
+      $series_definitions = \Drupal::service('entity_field.manager')->getFieldDefinitions('eventseries', 'eventseries');
+      $instance_definitions = \Drupal::service('entity_field.manager')->getFieldDefinitions('eventinstance', 'eventinstance');
+
+      if ($series_definitions[$values['sourceField']]->getType() !== $instance_definitions[$values['entityField']]->getType()) {
+        $message = $this->t('Source and entity field definition types must be the same to inherit data. Source - @source_name type: @source_type. Entity - @entity_name type: @entity_type', [
+          '@source_name' => $values['sourceField'],
+          '@source_type' => $series_definitions[$values['sourceField']]->getType(),
+          '@entity_name' => $values['entityField'],
+          '@entity_type' => $instance_definitions[$values['entityField']]->getType(),
+        ]);
+        $form_state->setErrorByName('sourceField', $message);
+        $form_state->setErrorByName('entityField', $message);
+      }
+
+      $plugin_definition = \Drupal::service('plugin.manager.field_inheritance')->getDefinition($values['plugin']);
+      $field_types = $plugin_definition['types'];
+
+      if (!in_array($series_definitions[$values['sourceField']]->getType(), $field_types)) {
+        $message = $this->t('The selected plugin @plugin does not support @source_type fields. The supported field types are: @field_types', [
+          '@plugin' => $values['plugin'],
+          '@source_type' => $series_definitions[$values['sourceField']]->getType(),
+          '@field_types' => implode(',', $field_types),
+        ]);
+        $form_state->setErrorByName('sourceField', $message);
+        $form_state->setErrorByName('plugin', $message);
+      }
+
+    }
+  }
+
   /**
    * {@inheritdoc}
    */
@@ -127,6 +165,7 @@ class FieldInheritanceForm extends EntityForm {
           '%label' => $field_inheritance->label(),
         ]));
     }
+    \Drupal::service('entity_field.manager')->clearCachedFieldDefinitions();
     $form_state->setRedirectUrl($field_inheritance->toUrl('collection'));
   }
 

src/Plugin/FieldInheritance/TextFieldInheritancePlugin.php → src/Plugin/FieldInheritance/StringFieldInheritancePlugin.php

@@ -3,14 +3,17 @@
 namespace Drupal\recurring_events\Plugin\FieldInheritance;
 
 /**
- * Text Inheritance plugin.
+ * String Inheritance plugin.
  *
  * @FieldInheritance(
- *   id = "text_inheritance",
- *   name = @Translation("Text Field Inheritance"),
+ *   id = "string_inheritance",
+ *   name = @Translation("String Field Inheritance"),
+ *   types = {
+ *     "string"
+ *   }
  * )
  */
-class TextFieldInheritancePlugin extends FieldInheritancePluginBase {
+class StringFieldInheritancePlugin extends FieldInheritancePluginBase {
 
   /**
    * Concatenation separator.

src/Plugin/FieldInheritance/TextLongFieldInheritancePlugin.php

@@ -8,6 +8,9 @@ namespace Drupal\recurring_events\Plugin\FieldInheritance;
  * @FieldInheritance(
  *   id = "text_long_inheritance",
  *   name = @Translation("Text Long Field Inheritance"),
+ *   types = {
+ *     "text_long"
+ *   }
  * )
  */
 class TextLongFieldInheritancePlugin extends FieldInheritancePluginBase {