diff --git a/tests/Spout/Reader/XLSXTest.php b/tests/Spout/Reader/XLSXTest.php
index 5856887..f1e3d99 100644
--- a/tests/Spout/Reader/XLSXTest.php
+++ b/tests/Spout/Reader/XLSXTest.php
@@ -129,6 +129,8 @@ class XLSXTest extends \PHPUnit_Framework_TestCase
                 \DateTime::createFromFormat('Y-m-d H:i:s', '2015-06-01 00:00:00'),
                 10, 10.43,
                 null,
+                'weird string', // valid 'str' string
+                null, // invalid date
             ],
             ['', '', '', '', '', '', '', '', ''],
         ];
diff --git a/tests/resources/xlsx/sheet_with_all_cell_types.xlsx b/tests/resources/xlsx/sheet_with_all_cell_types.xlsx
index 17b7303..ec109de 100644
Binary files a/tests/resources/xlsx/sheet_with_all_cell_types.xlsx and b/tests/resources/xlsx/sheet_with_all_cell_types.xlsx differ