diff --git a/core/tests/Variable/TestVariableSync.cpp b/core/tests/Variable/TestVariableSync.cpp
index a76e1df..539574d 100644
--- a/core/tests/Variable/TestVariableSync.cpp
+++ b/core/tests/Variable/TestVariableSync.cpp
@@ -1,6 +1,40 @@
 #include <QObject>
 #include <QtTest>
 
+#include <Variable/Variable.h>
+#include <Variable/VariableController.h>
+namespace {
+
+/**
+ * Interface representing an operation performed on a variable controller.
+ * This interface is used in tests to apply a set of operations and check the status of the
+ * controller after each operation
+ */
+struct IOperation {
+    virtual ~IOperation() = default;
+    /// Executes the operation on the variable controller
+    virtual void exec(VariableController &variableController) const = 0;
+};
+
+/**
+ * Test Iteration
+ *
+ * A test iteration includes an operation to be performed, and a set of expected ranges after each
+ * operation. Each range is tested after the operation to ensure that:
+ * - the range of the variable is the expected range
+ * - the data of the variable are those generated for the expected range
+ */
+struct Iteration {
+    std::shared_ptr<IOperation> m_Operation;  ///< Operation to perform
+    std::map<int, SqpRange> m_ExpectedRanges; ///< Expected ranges (by variable index)
+};
+
+using Iterations = std::vector<Iteration>;
+
+} // namespace
+
+Q_DECLARE_METATYPE(Iterations)
+
 class TestVariableSync : public QObject {
     Q_OBJECT