diff --git a/src/UploadedFileIntegrationTest.php b/src/UploadedFileIntegrationTest.php
index b00379b..2f99af9 100644
--- a/src/UploadedFileIntegrationTest.php
+++ b/src/UploadedFileIntegrationTest.php
@@ -108,7 +108,7 @@ public function testGetSize()
 
         $file = $this->createSubject();
         $size = $file->getSize();
-        if ($size) {
+        if (false !== $size) {
             // @TODO remove when package require phpunit 9.1
             if (function_exists('PHPUnit\Framework\assertMatchesRegularExpression')) {
                 $this->assertMatchesRegularExpression('|^[0-9]+$|', (string) $size);