尝试查看是否有任何JavaScript库功能可以合并两个json对象的特定键的值

var x ={ "student-marks":{'math':1,'physics':5} };
var y ={ "student-marks":{'chemistry':3,'history':2} };

使用$ .extend和$ .merge给出以下结果

$.extend({},x,y)  leads to  { "student-marks":{'chemistry':3,'history':2} }

$.merge(x,y) leads to { "student-marks":{'math':1,'physics':2} }

我正在寻找的是{ "student-marks":{'math':1,'physics':5, 'chemistry':3,'history':2} }‍