How to assign multiple values to a JavaScript object?

With ES6 Spread Operator:

someVar = {...someVar, color: "blue", font_size: "30px"}

With ES2015 you can use Object.assign:

const someVar = {
    color: "white",
    font_size: "30px",
    font_weight: "normal"
};

const newVar = Object.assign({}, someVar, { 
    color: "blue", 
    font_size: "30px"});

console.log(newVar);

=>

{
    color: "blue",
    font_size: "30px",
    font_weight: "normal"
}