feat(composition): added composition module stub

tests/composition/compositionTest.cpp

@@ -0,0 +1,21 @@
+#include <gtest/gtest.h>
+#include <string>
+#include <algorithm>
+
+#include "atomicSpecies.h"
+
+std::string EXAMPLE_FILENAME = std::string(getenv("MESON_SOURCE_ROOT")) + "/tests/composition/example.yaml";
+
+/**
+ * @brief Test suite for the composition class.
+ */
+class compositionTest : public ::testing::Test {};
+
+/**
+ * @brief Test the constructor of the composition class.
+ */
+TEST_F(compositionTest, constructor) {
+    std::cout << "Testing the constructor of the composition class." << std::endl;
+    std::cout << chemSpecies::species.at("H-1") << std::endl;
+}
+