Groups added to the 'Other groups' field are lost on submit

config/schema/og.schema.yml

@@ -116,3 +116,17 @@ og.og_role.*:
       sequence:
         type: string
         label: 'Permission'
+
+field.widget.settings.og_complex:
+  type: mapping
+  label: 'OG Group Audience field widget'
+  mapping:
+    match_operator:
+      type: string
+      label: 'Autocomplete matching'
+    size:
+      type: integer
+      label: 'Size of textfield'
+    placeholder:
+      type: label
+      label: 'Placeholder'

src/Og.php

@@ -9,6 +9,7 @@
 
 use Drupal\Component\Render\FormattableMarkup;
 use Drupal\Component\Utility\NestedArray;
+use Drupal\Core\Entity\Display\EntityFormDisplayInterface;
 use Drupal\Core\Entity\EntityInterface;
 use Drupal\Core\Entity\FieldableEntityInterface;
 use Drupal\Core\Field\FieldDefinitionInterface;
@@ -59,7 +60,7 @@ public static function createField($plugin_id, $entity_type, $bundle, array $set
 
     // Get the field definition and add the entity info to it. By doing so
     // we validate the the field can be attached to the entity. For example,
-    // the OG accesss module's field can be attached only to node entities, so
+    // the OG access module's field can be attached only to node entities, so
     // any other entity will throw an exception.
     /** @var \Drupal\og\OgFieldBase $og_field */
     $og_field = static::getFieldBaseDefinition($plugin_id)
@@ -72,7 +73,6 @@ public static function createField($plugin_id, $entity_type, $bundle, array $set
       FieldStorageConfig::create($field_storage_config)->save();
     }
 
-
     if (!$field_definition = FieldConfig::loadByName($entity_type, $bundle, $field_name)) {
       $field_config = NestedArray::mergeDeep($og_field->getFieldConfigBaseDefinition(), $settings['field_config']);
 
@@ -83,6 +83,34 @@ public static function createField($plugin_id, $entity_type, $bundle, array $set
       static::invalidateCache();
     }
 
+    // Make the field visible in the default form display.
+    /** @var EntityFormDisplayInterface $form_display */
+    $form_display = \Drupal::entityTypeManager()->getStorage('entity_form_display')->load("$entity_type.$bundle.default");
+
+    // If not found, create a fresh form display object. This is by design,
+    // configuration entries are only created when an entity form display is
+    // explicitly configured and saved.
+    // @see entity_get_form_display()
+    if (!$form_display) {
+      $form_display = \Drupal::entityTypeManager()->getStorage('entity_form_display')->create([
+        'targetEntityType' => $entity_type,
+        'bundle' => $bundle,
+        'mode' => 'default',
+        'status' => TRUE,
+      ]);
+    }
+
+    $widget = $form_display->getComponent($plugin_id);
+    $widget['type'] = 'og_complex';
+    $widget['settings'] = [
+      'match_operator' => 'CONTAINS',
+      'size' => 60,
+      'placeholder' => '',
+    ];
+
+    $form_display->setComponent($plugin_id, $widget);
+    $form_display->save();
+
     return $field_definition;
   }
 

src/Plugin/Field/FieldType/OgStandardReferenceItem.php

@@ -23,7 +23,7 @@
  *   default_widget = "og_complex",
  *   default_formatter = "og_complex",
  *   list_class = "\Drupal\Core\Field\EntityReferenceFieldItemList",
- *   constraints = {"ValidReference" = {}, "ValidOgMembershipReference" = {}}
+ *   constraints = {"ValidOgMembershipReference" = {}}
  * )
  */
 class OgStandardReferenceItem extends EntityReferenceItem {

src/Plugin/Field/FieldWidget/OgComplex.php

@@ -307,10 +307,13 @@ public function otherGroupsSingle($delta, EntityInterface $entity = NULL, $weigh
    * {@inheritdoc}
    */
   public function massageFormValues(array $values, array $form, FormStateInterface $form_state) {
-    $parent_values = $values;
+    // Remove empty values. The form fields may be empty.
+    $values = array_filter($values, function ($item) {
+      return !empty($item['target_id']);
+    });
 
     // Get the groups from the other groups widget.
-    foreach ($form['other_groups'] as $key => $value) {
+    foreach ($form[$this->fieldDefinition->getName()]['other_groups'] as $key => $value) {
       if (!is_int($key)) {
         continue;
       }
@@ -319,18 +322,16 @@ public function massageFormValues(array $values, array $form, FormStateInterface
       // be captured in it's own group, with the key 'id'.
       preg_match("|.+\((?<id>[\w.]+)\)|", $value['target_id']['#value'], $matches);
 
-      if (empty($matches['id'])) {
-        continue;
+      if (!empty($matches['id'])) {
+        $values[] = [
+          'target_id' => $matches['id'],
+          '_weight' => $value['_weight']['#value'],
+          '_original_delta' => $value['_weight']['#delta'],
+        ];
       }
-
-      $parent_values[] = [
-        'target_id' => $matches['id'],
-        '_weight' => $value['_weight']['#value'],
-        '_original_delta' => $value['_weight']['#delta'],
-      ];
     }
 
-    return $parent_values;
+    return $values;
   }
 
   /**

tests/src/Functional/OgComplexWidgetTest.php

@@ -0,0 +1,98 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\Tests\og\Functional\OgComplexWidgetTest.
+ */
+
+namespace Drupal\Tests\og\Functional;
+
+use Drupal\Core\Entity\Query\QueryInterface;
+use Drupal\node\Entity\Node;
+use Drupal\node\NodeInterface;
+use Drupal\og\Og;
+use Drupal\og\OgGroupAudienceHelper;
+use Drupal\og\Plugin\Field\FieldType\OgMembershipReferenceItemList;
+use Drupal\simpletest\BrowserTestBase;
+use Drupal\simpletest\ContentTypeCreationTrait;
+use Drupal\simpletest\NodeCreationTrait;
+
+/**
+ * Tests the complex widget.
+ *
+ * @group og
+ */
+class OgComplexWidgetTest extends BrowserTestBase {
+
+  use ContentTypeCreationTrait;
+  use NodeCreationTrait;
+
+  /**
+   * {@inheritdoc}
+   */
+  public static $modules = ['node', 'og'];
+
+  /**
+   * {@inheritdoc}
+   */
+  function setUp() {
+    parent::setUp();
+
+    // Create a "group" node type and turn it into a group type.
+    $this->createContentType(['type' => 'group']);
+    Og::groupManager()->addGroup('node', 'group');
+
+    // Add a group audience field to the "post" node type, turning it into a
+    // group content type.
+    $this->createContentType(['type' => 'post']);
+    Og::createField(OgGroupAudienceHelper::DEFAULT_FIELD, 'node', 'post');
+  }
+
+  /**
+   * Tests the "Other Groups" field.
+   */
+  function testOtherGroups() {
+    $admin_user = $this->drupalCreateUser(['administer group', 'access content', 'create post content']);
+    $group_owner = $this->drupalCreateUser(['access content', 'create post content']);
+
+    // Create a group content type owned by the group owner.
+    $settings = [
+      'type' => 'group',
+      'uid' => $group_owner->id(),
+    ];
+    $group = $this->createNode($settings);
+
+    // Log in as administrator.
+    $this->drupalLogin($admin_user);
+
+    // Create a new post in the group by using the "Other Groups" field in the
+    // UI.
+    $edit = [
+      'title[0][value]' => "Group owner's post.",
+      'other_groups[0][target_id]' => "group ({$group->id()})",
+    ];
+    $this->drupalGet('node/add/post');
+    $this->submitForm($edit, 'Save');
+    $this->assertSession()->statusCodeEquals(200);
+
+    // Retrieve the post that was created from the database.
+    /** @var QueryInterface $query */
+    $query = $this->container->get('entity.query')->get('node');
+    $result = $query
+      ->condition('type', 'post')
+      ->range(0, 1)
+      ->sort('nid', 'DESC')
+      ->execute();
+    $post_nid = reset($result);
+
+    /** @var NodeInterface $post */
+    $post = Node::load($post_nid);
+
+    // Check that the post references the group correctly.
+    /** @var OgMembershipReferenceItemList $reference_list */
+    $reference_list = $post->get(OgGroupAudienceHelper::DEFAULT_FIELD);
+    $this->assertEquals(1, $reference_list->count(), 'There is 1 reference after adding a group to the "Other Groups" field.');
+    $this->assertEquals($group->id(), $reference_list->first()->getValue()['target_id'], 'The "Other Groups" field references the correct group.');
+  }
+
+}