Issue #2923891 by JorgeLM, hl17, heddn, edysmp: Transliterate file names

src/Plugin/migrate/process/Transliteration.php

+<?php
+
+namespace Drupal\migrate_plus\Plugin\migrate\process;
+
+use Drupal\Component\Transliteration\TransliterationInterface;
+use Drupal\Core\Language\LanguageInterface;
+use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use Drupal\migrate\ProcessPluginBase;
+use Drupal\migrate\MigrateExecutableInterface;
+use Drupal\migrate\Row;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Transliterates text from Unicode to US-ASCII
+ *
+ * The transliteration process plugin takes the source value and runs it through
+ * the transliteration service. Letters will have language decorations and
+ * accents removed.
+ *
+ * Example:
+ *
+ * @code
+ * process:
+ *   bar:
+ *     plugin: transliteration
+ *     source: foo
+ * @endcode
+ *
+ * If the value of foo in the source is 'áéí!' then the destination value of bar
+ * will be 'aei!'.
+ *
+ * @see \Drupal\migrate\Plugin\MigrateProcessInterface
+ *
+ * @MigrateProcessPlugin(
+ *   id = "transliteration"
+ * )
+ */
+class Transliteration extends ProcessPluginBase implements ContainerFactoryPluginInterface {
+
+  /**
+   * The transliteration service.
+   *
+   * @var \Drupal\Component\Transliteration\TransliterationInterface
+   */
+  protected $transliteration;
+
+  /**
+   * Constructs a Transliteration plugin.
+   *
+   * @param array $configuration
+   *   The plugin configuration.
+   * @param string $plugin_id
+   *   The plugin ID.
+   * @param mixed $plugin_definition
+   *   The plugin definition.
+   * @param \Drupal\Component\Transliteration\TransliterationInterface $transliteration
+   *   The transliteration service.
+   */
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, TransliterationInterface $transliteration) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition);
+    $this->transliteration = $transliteration;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    return new static(
+      $configuration,
+      $plugin_id,
+      $plugin_definition,
+      $container->get('transliteration')
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function transform($value, MigrateExecutableInterface $migrate_executable, Row $row, $destination_property) {
+    return $this->transliteration->transliterate($value, LanguageInterface::LANGCODE_DEFAULT, '_');
+  }
+
+}
+

tests/src/Unit/process/TransliterationTest.php

+<?php
+
+namespace Drupal\Tests\migrate_plus\Unit\process;
+
+use Drupal\Component\Transliteration\PhpTransliteration;
+use Drupal\migrate\MigrateExecutableInterface;
+use Drupal\migrate\Row;
+use Drupal\migrate_plus\Plugin\migrate\process\Transliteration;
+use Drupal\Tests\migrate\Unit\process\MigrateProcessTestCase;
+
+/**
+ * Tests the transliteration process plugin.
+ *
+ * @group migrate_plus
+ */
+class TransliterationTest extends MigrateProcessTestCase {
+
+  /**
+   * A transliteration instance.
+   *
+   * @var \Drupal\Component\Transliteration\TransliterationInterface
+   */
+  protected $transliteration;
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    $this->transliteration = new PhpTransliteration();
+    $this->row = $this->getMockBuilder(Row::class)
+      ->disableOriginalConstructor()
+      ->getMock();
+    $this->migrateExecutable = $this->getMockBuilder(MigrateExecutableInterface::class)
+      ->disableOriginalConstructor()
+      ->getMock();
+    parent::setUp();
+  }
+
+  /**
+   * Tests transliteration transformation of non-alphanumeric characters.
+   */
+  public function testTransform() {
+    $actual = '9000004351_53494854_Spøgelsesjægerneáéö';
+    $expected_result = '9000004351_53494854_Spogelsesjaegerneaeo';
+
+    $plugin = new Transliteration([], 'transliteration', [], $this->transliteration);
+    $value = $plugin->transform($actual, $this->migrateExecutable, $this->row, 'destinationproperty');
+    $this->assertEquals($expected_result, $value);
+  }
+
+}