diff --git a/poincare/test/zoom.cpp b/poincare/test/zoom.cpp
index 3f74ff600..5edc65b5a 100644
--- a/poincare/test/zoom.cpp
+++ b/poincare/test/zoom.cpp
@@ -5,7 +5,7 @@
 
 using namespace Poincare;
 
-struct ParametersPack {
+class ParametersPack {
 public:
   ParametersPack(Expression expression, const char * symbol, Preferences::AngleUnit angleUnit) :
     m_expression(expression),