es6.this.js

var test = {
    result: "result",
    zero: function() {
        return this.result;
    },
    one: function() {
        return test.result;
    },
    two: () => {
        return this.result;
    },
    three: () => {
        return test.result;
    }
}

console.log(test["zero"]());  // #=> result
console.log(test["one"]());   // #=> result
console.log(test["two"]());   // #=> undefined
console.log(test["three"]()); // #=> result

// How can I use 'this', in test["two"]()?