Issue #2161177 by plopesc, yched: 'language' extra field doesn't display the language selected in the node form.

core/modules/node/lib/Drupal/node/NodeViewBuilder.php

@@ -50,7 +50,7 @@ class NodeViewBuilder extends EntityViewBuilder {
         $entity->content['langcode'] = array(
           '#type' => 'item',
           '#title' => t('Language'),
-          '#markup' => $this->languageManager->getLanguageName($langcode),
+          '#markup' => $entity->language()->name,
           '#prefix' => '<div id="field-language-display">',
           '#suffix' => '</div>'
         );

core/modules/node/lib/Drupal/node/Tests/NodeViewLanguageTest.php

@@ -0,0 +1,52 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\node\Tests\NodeViewLanguageTest.
+ */
+
+namespace Drupal\node\Tests;
+
+use Drupal\Core\Language\Language;
+
+/**
+ * Tests the node language extra field display.
+ */
+class NodeViewLanguageTest extends NodeTestBase {
+
+  /**
+   * Modules to enable.
+   *
+   * @var array
+   */
+  public static $modules = array('node', 'datetime', 'language');
+
+  public static function getInfo() {
+    return array(
+      'name' => 'Node view language field',
+      'description' => 'Tests the language extra field display.',
+      'group' => 'Node',
+    );
+  }
+
+  /**
+   * Tests the language extra field display.
+   */
+  public function testViewLanguage() {
+    // Add Spanish language.
+    $language = new Language(array('id' => 'es'));
+    language_save($language);
+
+    // Set language field visible.
+    entity_get_display('node', 'page', 'full')
+      ->setComponent('langcode')
+      ->save();
+
+    // Create a node in Spanish.
+    $node = $this->drupalCreateNode(array('langcode' => 'es'));
+
+    $this->drupalGet($node->getSystemPath());
+    $this->assertText('Spanish','The language field is displayed properly.');
+  }
+
+}