diff --git a/core/modules/field/src/Tests/String/RawStringFormatterTest.php b/core/modules/field/src/Tests/String/RawStringFormatterTest.php
index 60ea420..c175a22 100644
--- a/core/modules/field/src/Tests/String/RawStringFormatterTest.php
+++ b/core/modules/field/src/Tests/String/RawStringFormatterTest.php
@@ -124,6 +124,11 @@ public function testStringFormatter() {
     // Verify the cache tags.
     $build = $entity->{$this->fieldName}->view();
     $this->assertTrue(!isset($build[0]['#cache']), 'The string formatter has no cache tags.');
+
+    // Verify the render array of the field formatter.
+    $this->assertIdentical($build[0]['#type'], 'inline_template');
+    $this->assertIdentical($build[0]['#template'], '{{ value|nl2br }}');
+    $this->assertIdentical($build[0]['#context']['value'], $value);
   }
 
 }
diff --git a/core/modules/field/src/Tests/String/UuidFormatterTest.php b/core/modules/field/src/Tests/String/UuidFormatterTest.php
index 50ed4bf..fbd51d1 100644
--- a/core/modules/field/src/Tests/String/UuidFormatterTest.php
+++ b/core/modules/field/src/Tests/String/UuidFormatterTest.php
@@ -46,15 +46,23 @@ public function testUuidStringFormatter() {
 
     $uuid_field = $entity->get('uuid');
 
+    // Verify default build and render.
     $render_array = $uuid_field->view([]);
-    $value = $this->render($render_array);
-    $this->assertTrue(strpos($value, $entity->uuid()), 'The rendered UUID matches the entity UUID.');
+    $this->assertIdentical($render_array[0]['#type'], 'inline_template');
+    $this->assertIdentical($render_array[0]['#template'], '{{ value|nl2br }}');
+    $this->assertIdentical($render_array[0]['#context']['value'], $entity->uuid());
+    $this->assertTrue(strpos($this->render($render_array), $entity->uuid()), 'The rendered UUID found.');
 
+    // Verify customized build and render.
     $render_array = $uuid_field->view(['settings' => ['link_to_entity' => TRUE]]);
     $this->assertIdentical($render_array[0]['#type'], 'link');
+    $this->assertIdentical($render_array[0]['#title']['#type'], 'inline_template');
+    $this->assertIdentical($render_array[0]['#title']['#template'], '{{ value|nl2br }}');
+    $this->assertIdentical($render_array[0]['#title']['#context']['value'], $entity->uuid());
     $this->assertIdentical($render_array[0]['#url']->toString(), $entity->url());
-    $value = $this->render($render_array);
-    $this->assertTrue(strpos($value, $entity->uuid()));
+    $rendered = $this->render($render_array);
+    $this->assertTrue(strpos($rendered, $entity->uuid()), 'The rendered UUID found.');
+    $this->assertTrue(strpos($rendered, $entity->url()), 'The rendered entity URL found.');
   }
 
 }