Use concrete object types in side Panel

resources/js/app/components/relation-view/relations-add.js

@@ -370,7 +370,7 @@ export default {
 
                 return;
             }
-            if (this.relationTypes.right.length === 1) {
+            if (this.relationTypes?.right?.length === 1) {
                 this.object.type = this.relationTypes.right[0];
             } else {
                 this.object.type = '_choose';

resources/js/app/plugins/tinymce/placeholders.js

@@ -96,14 +96,15 @@ tinymce.util.Tools.resolve('tinymce.PluginManager').add('placeholders', function
 
     editor.ui.registry.addButton('placeholders', {
         icon: 'image',
-        tooltip: 'Add placeholder',
+        tooltip: t`Add placeholder`,
         onAction() {
             PanelEvents.requestPanel({
                 action: 'relations-add',
                 from: this,
                 data: {
                     relationName: 'placeholder',
                     relationLabel: 'Placeholder',
+                    relationTypes: {right: BEDITA?.relationsSchema?.placeholder?.right || null},
                 },
             });
 

src/Controller/ModulesController.php

@@ -561,8 +561,11 @@ private function setupViewRelations(array $relations): void
             $this->Properties->hiddenRelationsList($this->objectType),
             $this->Properties->readonlyRelationsList($this->objectType)
         );
+
+        // set right types, considering the object type relations
         $rel = (array)$this->viewBuilder()->getVar('relationsSchema');
         $rightTypes = \App\Utility\Schema::rightTypes($rel);
+        $this->set('rightTypes', $rightTypes);
 
         // set schemas for relations right types
         $schemasByType = $this->Schema->getSchemasByType($rightTypes);

src/View/Helper/LayoutHelper.php

@@ -296,6 +296,7 @@ public function metaConfig(): array
             'canSave' => $this->Perms->canSave(),
             'cloneConfig' => (array)Configure::read('Clone'),
             'uploadConfig' => $this->System->uploadConfig(),
+            'relationsSchema' => $this->getView()->get('relationsSchema', []),
         ];
     }
 

src/View/Helper/SchemaHelper.php

@@ -304,6 +304,7 @@ public function sortable(string $field): bool
      * Return unique right types from schema "relationsSchema".
      *
      * @return array
+     * @deprecated It will be removed in version 5.x.
      */
     public function rightTypes(): array
     {

templates/Element/Panel/relations_add.twig

@@ -23,7 +23,7 @@
                 </select>
             </div>
 
-            {% for type in Schema.rightTypes() %}
+            {% for type in rightTypes %}
                 {% set prefix = '_fast_create_' ~ type ~ '_' %}
                 {{ Form.create(null, {
                     'name': 'create-object',

tests/TestCase/View/Helper/LayoutHelperTest.php

@@ -421,6 +421,7 @@ public function testMetaConfig(): void
         $viewVars = [
             'modules' => ['documents' => [], 'images' => []],
             'uploadable' => ['images'],
+            'relationsSchema' => ['whatever'],
         ];
         $view = new View($request, null, null, compact('viewVars'));
         $layout = new LayoutHelper($view);
@@ -440,6 +441,7 @@ public function testMetaConfig(): void
             'canSave' => true,
             'cloneConfig' => (array)Configure::read('Clone'),
             'uploadConfig' => $system->uploadConfig(),
+            'relationsSchema' => ['whatever'],
         ];
         static::assertSame($expected, $conf);
     }

tests/TestCase/View/Helper/SchemaHelperTest.php

@@ -813,6 +813,7 @@ public function testRightTypes($relationsSchema, $expected): void
     {
         $view = $this->Schema->getView();
         $view->set('relationsSchema', $relationsSchema);
+        /** @phpstan-ignore-next-line */
         $actual = $this->Schema->rightTypes();
         static::assertSame($expected, $actual);
     }