Merge pull request #15 from Progmasoft/feature/catch3-runner

Replace Catch2's runner with the Catch3 runner

1 files changed, 22 insertions, 18 deletions

diff --git a/examples/232-Cfg-CustomMain.cpp b/examples/232-Cfg-CustomMain.cpp
index 27040993..6ef05fe7 100644
--- a/examples/232-Cfg-CustomMain.cpp
+++ b/examples/232-Cfg-CustomMain.cpp
@@ -7,35 +7,39 @@
 // 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
+// Show how to use custom main and read an option of your own before the
+// rest of the command line goes to the Catch3 runner.
+//
+// The runner starts this binary again for its worker processes, with the
+// same `main`: what happens before `run` happens in every worker too, which
+// is where global set-up belongs.
 
 #include <catch2/catch_session.hpp>
 
+#include <cstdlib>
 #include <iostream>
+#include <string>
+#include <vector>
 
 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
+  // Take our own option out of the command line; the runner reads the rest.
+  // Workers are started with the runner's options only, so a value they
+  // need too belongs in the environment, which they inherit.
+  std::vector<char const*> arguments;
+  for ( int i = 0; i < argc; ++i ) {
+      std::string const argument = argv[i];
+      if ( argument.rfind( "--height=", 0 ) == 0 ) {
+          height = std::atoi( argument.c_str() + 9 );
+      } else {
+          arguments.push_back( argv[i] );
+      }
+  }
 
-  // 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();
+  return session.run( static_cast<int>( arguments.size() ), arguments.data() );
 }