diff --git a/tests/Spout/Writer/ODS/Helper/StyleHelperTest.php b/tests/Spout/Writer/ODS/Helper/StyleHelperTest.php
index 46a73e7..1d0c7a5 100644
--- a/tests/Spout/Writer/ODS/Helper/StyleHelperTest.php
+++ b/tests/Spout/Writer/ODS/Helper/StyleHelperTest.php
@@ -35,8 +35,7 @@ class StyleHelperTest extends \PHPUnit_Framework_TestCase
         $this->assertNull($style2->getId());
 
         $styleHelper = new StyleHelper($this->defaultStyle);
-        $registeredStyles = $styleHelper->registerStyle($style1);
-        $registeredStyles = $styleHelper->registerStyle($style2);
+        $registeredStyles = $styleHelper->registerStyle([$style1, $style2]);
 
         $this->assertEquals(1, $registeredStyles[0]->getId());
         $this->assertEquals(2, $registeredStyles[1]->getId());
diff --git a/tests/Spout/Writer/XLSX/Helper/StyleHelperTest.php b/tests/Spout/Writer/XLSX/Helper/StyleHelperTest.php
index 4f276fd..30d7031 100644
--- a/tests/Spout/Writer/XLSX/Helper/StyleHelperTest.php
+++ b/tests/Spout/Writer/XLSX/Helper/StyleHelperTest.php
@@ -35,8 +35,7 @@ class StyleHelperTest extends \PHPUnit_Framework_TestCase
         $this->assertNull($style2->getId());
 
         $styleHelper = new StyleHelper($this->defaultStyle);
-        $registeredStyles = $styleHelper->registerStyle($style1);
-        $registeredStyles = $styleHelper->registerStyle($style2);
+        $registeredStyles = $styleHelper->registerStyle([$style1, $style2]);
 
         $this->assertEquals(1, $registeredStyles[0]->getId());
         $this->assertEquals(2, $registeredStyles[1]->getId());