diff --git a/tests/PhpSpreadsheetTests/Cell/AdvancedValueBinderTest.php b/tests/PhpSpreadsheetTests/Cell/AdvancedValueBinderTest.php
index eeb8ccdb..3fa8b69b 100644
--- a/tests/PhpSpreadsheetTests/Cell/AdvancedValueBinderTest.php
+++ b/tests/PhpSpreadsheetTests/Cell/AdvancedValueBinderTest.php
@@ -43,7 +43,7 @@ class AdvancedValueBinderTest extends TestCase
         StringHelper::setThousandsSeparator($this->thousandsSeparator);
     }
 
-    public function testNullValue()
+    public function testNullValue(): void
     {
         /** @var Cell&MockObject $cellStub */
         $cellStub = $this->getMockBuilder(Cell::class)
diff --git a/tests/data/Cell/DefaultValueBinder.php b/tests/data/Cell/DefaultValueBinder.php
index 35b1f4d9..f5dafc7b 100644
--- a/tests/data/Cell/DefaultValueBinder.php
+++ b/tests/data/Cell/DefaultValueBinder.php
@@ -80,5 +80,5 @@ return [
     'Numeric that exceeds PHP MAX_INT Size' => [
         's',
         '1234567890123459012345689012345690',
-    ]
+    ],
 ];