#define CATCH_CONFIG_MAIN // This tells Catch to provide a main() - only do this in one cpp file #include "catch2/catch.hpp" unsigned int Factorial( unsigned int number ) { return number <= 1 ? number : Factorial(number-1)*number; } TEST_CASE( "Factorials are computed", "[factorial]" ) { REQUIRE( Factorial(1) == 1 ); REQUIRE( Factorial(2) == 2 ); REQUIRE( Factorial(3) == 6 ); REQUIRE( Factorial(10) == 3628800 ); }