[FEATURE] Add PSR-14 Event before form deletion (#1312)

Documentation/ApiOverview/Events/Events/Form/BeforeFormIsDeletedEvent.rst

@@ -0,0 +1,40 @@
+..  include:: /Includes.rst.txt
+..  index:: Events; BeforeFormIsDeletedEvent
+
+..  _BeforeFormIsDeletedEvent:
+
+========================
+BeforeFormIsDeletedEvent
+========================
+
+..  versionadded:: 14.0
+    The event :php-short:`TYPO3\CMS\Form\Event\BeforeFormIsDeletedEvent`
+    is a more powerful replacement for the removed hook
+    :php:`$GLOBALS['TYPO3_CONF_VARS']['SC_OPTIONS']['ext/form']['beforeFormDelete']`.
+
+The event :php-short:`TYPO3\CMS\Form\Event\BeforeFormIsDeletedEvent`
+can prevent the deletion of a form and add custom logic based on the delete
+action. The event is dispatched just before a form is deleted in the backend.
+
+Setting :php:`$preventDeletion` to
+:php:`true`, stops the event and no further listener is called.
+
+..  seealso::
+    *   The backend form editor is described in detail in the `TYPO3 Form manual
+        - Form editor <https://docs.typo3.org/permalink/typo3/cms-form:apireference-formeditor>`_.
+
+..  _BeforeFormIsDeletedEvent-example:
+
+Example
+=======
+
+..  literalinclude:: _BeforeFormIsDeletedEvent/_MyEventListener.php
+    :language: php
+    :caption: EXT:my_extension/Classes/EventListener/MyEventListener.php
+
+..  _BeforeFormIsDeletedEvent-api:
+
+API
+===
+
+..  include:: /CodeSnippets/Events/Form/BeforeFormIsDeletedEvent.rst.txt

Documentation/ApiOverview/Events/Events/Form/_BeforeFormIsDeletedEvent/_MyEventListener.php

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+<?php
+
+declare(strict_types=1);
+
+namespace MyVendor\MyExtension\EventListener;
+
+use TYPO3\CMS\Core\Attribute\AsEventListener;
+use TYPO3\CMS\Form\Event\BeforeFormIsDeletedEvent;
+
+#[AsEventListener(
+    identifier: 'my-extension/before-form-is-deleted',
+)]
+final readonly class MyEventListener
+{
+    public function __invoke(BeforeFormIsDeletedEvent $event): void
+    {
+        if ($event->formPersistenceIdentifier === 'some-identifier') {
+            $event->preventDeletion = true;
+        }
+    }
+}

Documentation/CodeSnippets/Config/Api/Events/EventsForm.php

@@ -19,6 +19,12 @@
         'targetFileName' => 'CodeSnippets/Events/Form/BeforeFormIsCreatedEvent.rst.txt',
         'withCode' => false,
     ],
+    [
+        'action' => 'createPhpClassDocs',
+        'class' => \TYPO3\CMS\Form\Event\BeforeFormIsDeletedEvent::class,
+        'targetFileName' => 'CodeSnippets/Events/Form/BeforeFormIsDeletedEvent.rst.txt',
+        'withCode' => false,
+    ],
     [
         'action' => 'createPhpClassDocs',
         'class' => \TYPO3\CMS\Form\Event\BeforeRenderableIsAddedToFormEvent::class,

Documentation/CodeSnippets/Events/Form/BeforeFormIsDeletedEvent.rst.txt

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+..  Generated by https://github.com/TYPO3-Documentation/t3docs-codesnippets
+..  php:namespace::  TYPO3\CMS\Form\Event
+
+..  php:class:: BeforeFormIsDeletedEvent
+
+    Listeners to this event will be able to prevent deletion of a form and/or
+    add custom logic.
+
+    ..  php:attr:: formPersistenceIdentifier
+        :readonly:
+        :public:
+
+    ..  php:attr:: preventDeletion
+        :public:
+        :returns: `bool`