* 将源对象(source)的所有可枚举且目标对象(target)不存在的属性, 复制到目标对象 * @param {object} target 目标对象 * @param {object} source 源对象 * @param {boolean} forced 是否强制复制, 为true时将会覆盖目标对象同名属性, 默认为false
(target, source, forced)
source not stored for this graph (policy: none)
no outgoing calls
no test coverage detected