我正在对以下代码片段执行SourceFileObject.getNamedDeclarations操作：

module Mankala {
  export class Rectangle {
    x: number;
    y: number;
    width: number;
    height: number;
    square() {
    }
  }
}

这返回一个缺少属性'height'的数组。问题出在
SourceFileObject.prototype.getNamedDeclarations

case 125 /* Method */:
             var functionDeclaration = node;
             if (functionDeclaration.name && functionDeclaration.name.getFullWidth() > 0) {
             var lastDeclaration = namedDeclarations.length > 0 ? namedDeclarations[namedDeclarations.length - 1] : undefined;
                                if (lastDeclaration && functionDeclaration.symbol === lastDeclaration.symbol) {
                                    if (functionDeclaration.body && !lastDeclaration.body) {
                                        namedDeclarations[namedDeclarations.length - 1] = functionDeclaration;
                                    }
                                }

functionDeclaration.symbol === lastDeclaration.symbol为true,因为两个符号都是未定义的。然后，属性'height'被替换为方法'square'。