vendor Catch2 and ETL

contrib/fsfw_contrib/Catch2-3.7.1/examples/232-Cfg-CustomMain.cpp

@@ -0,0 +1,41 @@
+
+//              Copyright Catch2 Authors
+// Distributed under the Boost Software License, Version 1.0.
+//   (See accompanying file LICENSE.txt or copy at
+//        https://www.boost.org/LICENSE_1_0.txt)
+
+// SPDX-License-Identifier: BSL-1.0
+
+// 232-Cfg-CustomMain.cpp
+// Show how to use custom main and add a custom option to the CLI parser
+
+#include <catch2/catch_session.hpp>
+
+#include <iostream>
+
+int main(int argc, char** argv) {
+  Catch::Session session; // There must be exactly one instance
+
+  int height = 0; // Some user variable you want to be able to set
+
+  // Build a new parser on top of Catch2's
+  using namespace Catch::Clara;
+  auto cli
+    = session.cli()           // Get Catch2's command line parser
+    | Opt( height, "height" ) // bind variable to a new option, with a hint string
+         ["--height"]         // the option names it will respond to
+         ("how high?");       // description string for the help output
+
+  // Now pass the new composite back to Catch2 so it uses that
+  session.cli( cli );
+
+  // Let Catch2 (using Clara) parse the command line
+  int returnCode = session.applyCommandLine( argc, argv );
+  if( returnCode != 0 ) // Indicates a command line error
+      return returnCode;
+
+  // if set on the command line then 'height' is now set at this point
+  std::cout << "height: " << height << '\n';
+
+  return session.run();
+}