Issue #2584745 by mbovan, s_leu: Entity references should be displayed...

Issue #2584745 by mbovan, s_leu: Entity references should be displayed translated on non translatable  entity types

core/lib/Drupal/Core/Entity/Entity/EntityViewDisplay.php

@@ -13,6 +13,7 @@
 use Drupal\Core\Entity\EntityStorageInterface;
 use Drupal\Core\Entity\FieldableEntityInterface;
 use Drupal\Core\Entity\EntityDisplayBase;
+use Drupal\Core\TypedData\TranslatableInterface;
 
 /**
  * Configuration entity that contains display options for all components of a
@@ -249,7 +250,18 @@ public function buildMultiple(array $entities) {
           $items = $grouped_items[$id];
           /** @var \Drupal\Core\Access\AccessResultInterface $field_access */
           $field_access = $items->access('view', NULL, TRUE);
-          $build_list[$id][$name] = $field_access->isAllowed() ? $formatter->view($items, $entity->language()->getId()) : [];
+          // The language of the field values to display is already determined
+          // in the incoming $entity. The formatter should build its output of
+          // those values using:
+          // - the entity language if the entity is translatable,
+          // - the current "content language" otherwise.
+          if ($entity instanceof TranslatableInterface && $entity->isTranslatable()) {
+            $view_langcode = $entity->language()->getId();
+          }
+          else {
+            $view_langcode = NULL;
+          }
+          $build_list[$id][$name] = $field_access->isAllowed() ? $formatter->view($items, $view_langcode) : [];
           // Apply the field access cacheability metadata to the render array.
           $this->renderer->addCacheableDependency($build_list[$id][$name], $field_access);
         }

core/modules/field/src/Tests/EntityReference/EntityReferenceFieldTranslatedReferenceViewTest.php

@@ -140,9 +140,26 @@ protected function setUp() {
   }
 
   /**
-   * Tests if the translated entity is displayed in an entity reference field.
+   * Tests if the entity is displayed in an entity reference field.
    */
-  public function testTranslatedEntityReferenceDisplay() {
+  public function testEntityReferenceDisplay() {
+    // Create a translated referrer entity.
+    $this->referrerEntity = $this->createReferrerEntity();
+    $this->assertEntityReferenceDisplay();
+
+    // Disable translation for referrer content type.
+    $this->drupalLogin($this->rootUser);
+    $this->drupalPostForm('admin/config/regional/content-language', ['settings[node][referrer][translatable]' => FALSE], t('Save configuration'));
+
+    // Create a referrer entity without translation.
+    $this->referrerEntity = $this->createReferrerEntity(FALSE);
+    $this->assertEntityReferenceDisplay();
+  }
+
+  /**
+   * Assert entity reference display.
+   */
+  protected function assertEntityReferenceDisplay() {
     $url = $this->referrerEntity->urlInfo();
     $translation_url = $this->referrerEntity->urlInfo('canonical', ['language' => ConfigurableLanguage::load($this->translateToLangcode)]);
 
@@ -169,7 +186,6 @@ protected function setUpLanguages() {
   protected function createContent() {
     $this->referencedEntityWithTranslation = $this->createReferencedEntityWithTranslation();
     $this->referencedEntityWithoutTranslation = $this->createNotTranslatedReferencedEntity();
-    $this->referrerEntity = $this->createReferrerEntity();
   }
 
   /**
@@ -283,7 +299,7 @@ protected function createNotTranslatedReferencedEntity() {
   /**
    * Create the referrer entity.
    */
-  protected function createReferrerEntity() {
+  protected function createReferrerEntity($translatable = TRUE) {
     /** @var \Drupal\node\Entity\Node $node */
     $node = entity_create($this->testEntityTypeName, array(
       'title' => $this->randomMachineName(),
@@ -298,8 +314,9 @@ protected function createReferrerEntity() {
       ),
       'langcode' => $this->baseLangcode,
     ));
-    $node->save();
-    $node->addTranslation($this->translateToLangcode, $node->toArray());
+    if ($translatable) {
+      $node->addTranslation($this->translateToLangcode, $node->toArray());
+    }
     $node->save();
 
     return $node;