"ReactiveSequence is not supposed to reach this point" happens when some children are skipped

[torydebra]

Hi,
I am using a ReactiveSequence with _skipIf preconditions on the children, and it throws:

terminate called after throwing an instance of 'BT::LogicError'
  what():  ReactiveSequence is not supposed to reach this point

Looking at the code

BehaviorTree.CPP/src/controls/reactive_sequence.cpp

Lines 54 to 72 in 109eccd

	case NodeStatus::SKIPPED: {
	// node skipped
	}
	break;
	case NodeStatus::IDLE: {
	throw LogicError("[", name(), "]: A children should not return IDLE");
	}
	} // end switch
	} //end for
	if (success_count == childrenCount())
	{
	resetChildren();
	// Skip if ALL the nodes have been skipped
	return status() == (NodeStatus::RUNNING) ? NodeStatus::SUCCESS : NodeStatus::SKIPPED;
	}
	throw LogicError("ReactiveSequence is not supposed to reach this point");

it seems that this happens because if a children is SKIPPED the success_count is not increased, neither the method returns, ending in the throw. Am I right?

I can provide simple example if necessary to replicate this

[facontidavide]

yes, a simple example would be really great. I will fix this as soon as I receive it

[torydebra]

Here you are:

#include "behaviortree_cpp/bt_factory.h"

using namespace BT;

// clang-format off
static const char* xml_text = R"(

<root BTCPP_format="4">
  <BehaviorTree ID="Untitled">
    <ReactiveSequence>
      <AlwaysSuccess _skipIf="flag"/>
    </ReactiveSequence>
  </BehaviorTree>
</root>

 )";

// clang-format on

int main()
{
  BehaviorTreeFactory factory;
  
  auto root_blackboard = BT::Blackboard::create();
  root_blackboard->set<bool>("flag", true);
  
  auto tree = factory.createTreeFromText(xml_text, root_blackboard);    
    
  tree.tickWhileRunning();
  
  return 0;
}

[facontidavide]

Fixed. Thank for reporting