Running sum O(n) Leetcode

runningSum.js

/**
 * @param {number[]} nums
 * @return {number[]}
 */
var runningSum = function(nums) {
    let newNums = [];
    let numsSum = 0;
    nums.forEach((num,i) =>{
            
        if(nums[i] !== null){
         numsSum += nums[i]
          newNums.push(numsSum)   
       
        }
    })
            return newNums;

};

//O(n) runs through array once