Update to Drupal 8.0.6. For more information, see https://www.drupal.org/drupal-8.0.6-release-notes

core/modules/taxonomy/migration_templates/d6_vocabulary_field.yml

@@ -8,7 +8,6 @@ source:
     entity_type: node
     type: entity_reference
     target_entity_type: taxonomy_term
-    cardinality: -1
 process:
   entity_type: 'constants/entity_type'
   type: 'constants/type'
@@ -21,7 +20,7 @@ process:
       plugin: skip_on_empty
       method: row
   'settings/target_type': 'constants/target_entity_type'
-  cardinality: 'constants/cardinality'
+  cardinality: cardinality
 destination:
   plugin: md_entity:field_storage_config
 migration_dependencies:

core/modules/taxonomy/src/Form/OverviewTerms.php

@@ -27,7 +27,7 @@ class OverviewTerms extends FormBase {
   protected $moduleHandler;
 
   /**
-   * The term storage controller.
+   * The term storage handler.
    *
    * @var \Drupal\taxonomy\TermStorageInterface
    */

core/modules/taxonomy/src/Plugin/migrate/source/d6/Vocabulary.php

@@ -9,6 +9,7 @@ namespace Drupal\taxonomy\Plugin\migrate\source\d6;
 
 use Drupal\migrate\Row;
 use Drupal\migrate_drupal\Plugin\migrate\source\DrupalSqlBase;
+use Drupal\Core\Field\FieldStorageDefinitionInterface;
 
 /**
  * Drupal 6 vocabularies source from database.
@@ -72,6 +73,7 @@ class Vocabulary extends DrupalSqlBase {
       ->execute()
       ->fetchCol();
     $row->setSourceProperty('node_types', $node_types);
+    $row->setSourceProperty('cardinality', ($row->getSourceProperty('tags') == 1 || $row->getSourceProperty('multiple') == 1) ?  FieldStorageDefinitionInterface::CARDINALITY_UNLIMITED : 1);
     return parent::prepareRow($row);
   }
 

core/modules/taxonomy/src/TermForm.php

@@ -11,7 +11,7 @@ use Drupal\Core\Entity\ContentEntityForm;
 use Drupal\Core\Form\FormStateInterface;
 
 /**
- * Base for controller for taxonomy term edit forms.
+ * Base for handler for taxonomy term edit forms.
  */
 class TermForm extends ContentEntityForm {
 

core/modules/taxonomy/src/TermViewBuilder.php

@@ -12,7 +12,7 @@ use Drupal\Core\Entity\EntityInterface;
 use Drupal\Core\Entity\EntityViewBuilder;
 
 /**
- * Render controller for taxonomy terms.
+ * View builder handler for taxonomy terms.
  */
 class TermViewBuilder extends EntityViewBuilder {
 

core/modules/taxonomy/src/Tests/Migrate/d6/MigrateVocabularyFieldInstanceTest.php

@@ -10,6 +10,7 @@ namespace Drupal\taxonomy\Tests\Migrate\d6;
 use Drupal\field\Entity\FieldConfig;
 use Drupal\migrate\Entity\Migration;
 use Drupal\migrate_drupal\Tests\d6\MigrateDrupal6TestBase;
+use Drupal\taxonomy\Entity\Vocabulary;
 
 /**
  * Vocabulary field instance migration.

core/modules/taxonomy/src/Tests/Migrate/d6/MigrateVocabularyFieldTest.php

@@ -37,11 +37,13 @@ class MigrateVocabularyFieldTest extends MigrateDrupal6TestBase {
   public function testVocabularyField() {
     // Test that the field exists.
     $field_storage_id = 'node.tags';
+    /** @var \Drupal\field\FieldStorageConfigInterface $field_storage */
     $field_storage = FieldStorageConfig::load($field_storage_id);
     $this->assertIdentical($field_storage_id, $field_storage->id());
 
     $settings = $field_storage->getSettings();
     $this->assertIdentical('taxonomy_term', $settings['target_type'], "Target type is correct.");
+    $this->assertIdentical(1, $field_storage->getCardinality(), "Field cardinality in 1.");
 
     $this->assertIdentical(array('node', 'tags'), Migration::load('d6_vocabulary_field')->getIdMap()->lookupDestinationID(array(4)), "Test IdMap");
   }

core/modules/taxonomy/src/VocabularyStorage.php

@@ -10,7 +10,7 @@ namespace Drupal\taxonomy;
 use Drupal\Core\Config\Entity\ConfigEntityStorage;
 
 /**
- * Defines a controller class for taxonomy vocabularies.
+ * Defines a storage handler class for taxonomy vocabularies.
  */
 class VocabularyStorage extends ConfigEntityStorage implements VocabularyStorageInterface {
 

core/modules/taxonomy/tests/src/Unit/Migrate/d6/VocabularyTest.php

@@ -8,6 +8,7 @@
 namespace Drupal\Tests\taxonomy\Unit\Migrate\d6;
 
 use Drupal\Tests\migrate\Unit\MigrateSqlSourceTestCase;
+use Drupal\Core\Field\FieldStorageDefinitionInterface;
 
 /**
  * Tests D6 vocabulary source plugin.
@@ -39,6 +40,7 @@ class VocabularyTest extends MigrateSqlSourceTestCase {
       'module' => 'taxonomy',
       'weight' => 0,
       'node_types' => ['page', 'article'],
+      'cardinality' => FieldStorageDefinitionInterface::CARDINALITY_UNLIMITED,
     ],
     [
       'vid' => 2,
@@ -53,6 +55,7 @@ class VocabularyTest extends MigrateSqlSourceTestCase {
       'module' => 'taxonomy',
       'weight' => 0,
       'node_types' => ['article'],
+      'cardinality' => 1,
     ],
   ];