code: function(node, state, leaving) {
          for (let i = 0; i < state.currentSegments.length; ++i) {
              const segInternal = state.currentSegments[i].internal;
  
              if (leaving) {
                  segInternal.exitNodes.push(node);
              } else {
                  segInternal.nodes.push(node);
              }
          }
  
          debug([
              `${state.currentSegments.map(getId).join(",")})`,
              `${node.type}${leaving ? ":exit" : ""}`
          ].join(" "));
      }
docs: /* istanbul ignore next