diff --git a/core/tests/Drupal/Tests/Component/Diff/DiffEngineTest.php b/core/tests/Drupal/Tests/Component/Diff/DiffEngineTest.php
deleted file mode 100644
index 97c1f57..0000000
--- a/core/tests/Drupal/Tests/Component/Diff/DiffEngineTest.php
+++ /dev/null
@@ -1,79 +0,0 @@
-<?php
-
-/**
- * @file
- * Contains \Drupal\Tests\Component\DiffEngineTest.
- */
-
-namespace Drupal\Tests\Component;
-
-use Drupal\Tests\UnitTestCase;
-
-/**
- * Tests the DiffEngine class.
- */
-class DiffEngineTest extends UnitTestCase {
-
-    /**
-     * Lines array to use for testing.
-     *
-     * @var array
-     */
-    protected $lines1;
-
-    /**
-     * Lines array to use for testing.
-     *
-     * @var array
-     */
-    protected $lines2;
-
-    public static function getInfo() {
-        return array(
-            'name' => 'DiffEngine',
-            'description' => 'Tests the DiffEngine class.',
-            'group' => 'System',
-        );
-    }
-
-    function setUp() {
-        parent::setUp();
-
-        $this->lines1 = array(
-            'Hello World',
-            'I am an original line'
-        );
-
-        $this->lines2 = array(
-            'Hello World',
-            'I am a new line',
-            'I am an original line'
-        );
-    }
-
-    /**
-     * Tests Diff::Diff().
-     */
-    public function testDiff() {
-        define('DRUPAL_ROOT', __DIR__ .'/../../../../../../');
-        require_once DRUPAL_ROOT . '/core/lib/Drupal/Component/Diff/DiffEngine.php';
-
-        $diff = new \Diff($this->lines1, $this->lines2);
-
-        $expected = array(
-            new \_DiffOp_Copy(array('Hello World')),
-            new \_DiffOp_Add(array('I am a new line')),
-            new \_DiffOp_Copy(array('I am an original line'))
-        );
-
-        $this->assertCount(count($expected), $diff->edits);
-
-        foreach($diff->edits as $key => $diffObject) {
-            $this->assertInstanceOf(get_class($expected[$key]), $diffObject);
-            $this->assertSame($expected[$key]->orig, $diffObject->orig);
-            $this->assertSame($expected[$key]->closing, $diffObject->closing);
-        }
-
-    }
-
-}