diff --git a/core/lib/Drupal/Core/Template/TwigExtension.php b/core/lib/Drupal/Core/Template/TwigExtension.php
index f7991be..b9ad12c 100644
--- a/core/lib/Drupal/Core/Template/TwigExtension.php
+++ b/core/lib/Drupal/Core/Template/TwigExtension.php
@@ -70,8 +70,8 @@ public function getFunctions() {
     return array(
       // This function will receive a renderable array, if an array is detected.
       new \Twig_SimpleFunction('render', 'twig_render_var'),
-      // render and render_var do the same thing. render_var is only kept for
-      // backwards compatibility.
+      // 'render' and 'render_var' do the same thing. 'render_var' is only kept
+      // for backwards compatibility.
       new \Twig_SimpleFunction('render_var', 'twig_render_var'),
       // The url and path function are defined in close parallel to those found
       // in \Symfony\Bridge\Twig\Extension\RoutingExtension
diff --git a/core/modules/system/src/Tests/Theme/TwigFunctionTest.php b/core/modules/system/src/Tests/Theme/TwigFunctionTest.php
index 0f76a5f..0ea63ca 100644
--- a/core/modules/system/src/Tests/Theme/TwigFunctionTest.php
+++ b/core/modules/system/src/Tests/Theme/TwigFunctionTest.php
@@ -27,31 +27,39 @@ class TwigFunctionTest extends KernelTestBase {
    * Tests the Twig 'render' function.
    */
   public function testTwigRenderFunction() {
-    $element = [
-      '#type' => 'inline_template',
-      '#template' => '{% set cats = render(animals.some_cats_i_know) %}{{ cats }}',
-      '#context' => ['animals' => [
-        'some_cats_i_know' => [
-          '#theme' => 'item_list',
-          '#title' => t('Some cats I know'),
-          '#items' => [
-            'Wyatt',
-            'Puck',
-          ],
+    $animals = [
+      'cats' => [
+        '#theme' => 'item_list',
+        '#title' => 'Some cats I know',
+        '#items' => [
+          'Wyatt',
+          'Puck',
         ],
-        'some_dogs_i_know' => [
-          '#theme' => 'item_list',
-          '#title' => t('Some dogs I know'),
-          '#items' => [
-            'Otis',
-            'Peanut',
-          ],
+      ],
+      'dogs' => [
+        '#theme' => 'item_list',
+        '#title' => 'Some dogs I know',
+        '#items' => [
+          'Otis',
+          'Peanut',
         ],
-      ]],
+      ],
+    ];
+    $cats = [
+      '#type' => 'inline_template',
+      '#template' => '{% set cats = render(animals.cats) %}{{ cats }}',
+      '#context' => ['animals' => $animals],
     ];
+    $rendered_cats = \Drupal::service('renderer')->render($cats);
+    $this->assertEqual($rendered_cats, '<div><h3>Some cats I know</h3><ul><li>Wyatt</li><li>Puck</li></ul></div>');
 
-    $rendered = \Drupal::service('renderer')->render($element);
-    $this->assertEqual($rendered, '<div><h3>Some cats I know</h3><ul><li>Wyatt</li><li>Puck</li></ul></div>');
+    $dogs = [
+      '#type' => 'inline_template',
+      '#template' => '{% set dogs = render(animals.dogs)|striptags %}{{ dogs }}',
+      '#context' => ['animals' => $animals],
+    ];
+    $rendered_dogs = \Drupal::service('renderer')->render($dogs);
+    $this->assertEqual($rendered_dogs, 'Some dogs I knowOtisPeanut');
   }
 
 }