Method projectPath

packages/graph/src/Steps.ts:6849–6897

(
    path: TraversalPath<any, any, any>,
    items: readonly WithItemConfig[],
    context?: QueryContext,
  )

  }

  protected projectPath(
    path: TraversalPath<any, any, any>,
    items: readonly WithItemConfig[],
    context?: QueryContext,
  ): TraversalPath<any, any, any> | undefined {
    // Start a new path with the first item's value
    let newPath: TraversalPath<any, any, any> | undefined;

    for (const item of items) {
      let value: any;

      switch (item.type) {
        case "variable": {
          const pathNode = path.get(item.sourceVariable);
          if (!pathNode) return undefined; // Variable not found
          value = pathNode.value;
          break;
        }
        case "property": {
          const pathNode = path.get(item.sourceVariable);
          if (!pathNode) return undefined;
          value = pathNode.property(item.property as never);
          break;
        }
        case "aggregate":
          // Aggregates are handled separately in computeAggregates
          continue;
        case "functionCall": {
          // Evaluate function call
          const resolvedArgs = item.args.map((arg) => resolveConditionValue(path, arg, context));
          value = evaluateFunction(item.functionName, resolvedArgs, path, item.distinct);
          break;
        }
        case "expression": {
          // Evaluate arbitrary expression (e.g., list literals)
          value = resolveConditionValue(path, item.value, context);
          break;
        }
      }

      if (!newPath) {
        newPath = new TraversalPath(undefined, value, [item.alias]);
      } else {
        newPath = newPath.with(value, [item.alias]);
      }
    }

    return newPath;
  }

  protected computeAggregates(
    paths: readonly TraversalPath<any, any, any>[],