moved from Catch to doctest for unit tests

test/src/unit-inspection.cpp

@@ -27,12 +27,14 @@ OUT OF OR IN CONNECTION WITH THE SOFTWARE  OR THE USE OR OTHER DEALINGS IN THE
 SOFTWARE.
 */
 
-#include "catch.hpp"
+#include "doctest_compatibility.h"
 
-#include <fstream>
 #include <nlohmann/json.hpp>
 using nlohmann::json;
 
+#include <fstream>
+#include <sstream>
+
 TEST_CASE("object inspection")
 {
     SECTION("convenience type checker")