Issue #3502063

1. Added a new filter that transform input to the machine-readable names

Related to #3502063

src/Plugin/FapiValidationFilter/MachineNameFilter.php

+<?php
+
+namespace Drupal\fapi_validation\Plugin\FapiValidationFilter;
+
+use Drupal\Component\Transliteration\TransliterationInterface;
+use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use Drupal\Core\StringTranslation\TranslatableMarkup;
+use Drupal\fapi_validation\Attribute\FapiValidationFilter;
+use Drupal\fapi_validation\FapiValidationFiltersInterface;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Fapi Validation Plugin for Machine name filter.
+ */
+#[FapiValidationFilter(
+  id: 'machine_name',
+  label: new TranslatableMarkup('Machine name'),
+  description: new TranslatableMarkup('Transform input values into machine-readable names.'),
+)]
+class MachineNameFilter implements FapiValidationFiltersInterface, ContainerFactoryPluginInterface {
+
+  /**
+   * Constructs a MachineNameFilter object.
+   */
+  public function __construct(
+    array $configuration,
+    string $plugin_id,
+    array $plugin_definition,
+    protected TransliterationInterface $transliteration
+  ) { }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    return new static(
+      $configuration,
+      $plugin_id,
+      $plugin_definition,
+      $container->get('transliteration')
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function filter($value) {
+    $transliterated = $this->transliteration->transliterate($value, 'en', '_');
+    $transliterated = mb_strtolower($transliterated);
+
+    return preg_replace('@' . strtr('[^a-z0-9_]+', ['@' => '\@', chr(0) => '']) . '@', '_', $transliterated);
+  }
+
+}