diff --git a/core/tests/Drupal/Tests/Phpunit5FCTrait.php b/core/tests/Drupal/Tests/Phpunit5FCTrait.php
index d539f4333d..9a123ada13 100644
--- a/core/tests/Drupal/Tests/Phpunit5FCTrait.php
+++ b/core/tests/Drupal/Tests/Phpunit5FCTrait.php
@@ -110,20 +110,24 @@ private function isPhpunit5() {
   }
 
   /**
-   * @todo
+   * Compatibility layer for PHPUnit 6 to support PHPUnit 4 code.
    *
-   * @param $class
-   * @param null $message
+   * @param mixed $class
+   * @param string $message
+   * @param int $exception_code
    */
-  public function setExpectedException($class, $message = NULL) {
+  public function setExpectedException($class, $message = '', $exception_code = NULL) {
     if (method_exists($this, 'expectException')) {
       $this->expectException($class);
-      if ($message !== NULL) {
+      if (!empty($message)) {
         $this->expectExceptionMessage($message);
       }
+      if ($exception_code !== NULL) {
+        $this->expectExceptionCode($exception_code);
+      }
     }
     else {
-      parent::setExpectedException($class, $message);
+      parent::setExpectedException($class, $message, $exception_code);
     }
   }