if (outcome != expected) {
XBT_ERROR("Expected %s but got %s in %s", to_string(expected), to_string(outcome), scenario_string.c_str());
} else {
if (outcome != expected) {
XBT_ERROR("Expected %s but got %s in %s", to_string(expected), to_string(outcome), scenario_string.c_str());
} else {