diff --git a/tests/src/Kernel/ServerTaskTest.php b/tests/src/Kernel/ServerTaskTest.php
index 690496c..7dd94eb 100644
--- a/tests/src/Kernel/ServerTaskTest.php
+++ b/tests/src/Kernel/ServerTaskTest.php
@@ -237,7 +237,7 @@ class ServerTaskTest extends KernelTestBase {
       $this->fail('Pending server tasks did not prevent indexing of items.');
     }
     catch (SearchApiException $e) {
-      $expected_message = "Could not index items on index {$this->index->label()} because pending server tasks could not be executed.";
+      $expected_message = "Could not index items on index '{$this->index->label()}' because pending server tasks could not be executed.";
       $this->assertEquals($expected_message, $e->getMessage(), 'Pending server tasks prevented indexing of items.');
     }
     $this->assertEquals(array(), $this->getCalledBackendMethods(), 'indexItems was not executed.');