Write to the specific key of the object -> `pathToWriteTo(['/', 'a'], 'myData')` -> `{'/': {'a': 'myData'}}`

pathToWriteTo.ts

// Write to the specific key of the object
// pathToWriteTo(['/', 'a'], 'myData')
// will write to -> {'/': {'a': 'myData'}}
function pathToWriteTo(
  pathArr: string[],
  input: { [key: string]: {} },
  fs: { [key: string]: {} }
) {
  let level: { [key: string]: {} } = fs;
  let index = 0;

  for (let path of pathArr) {
    // if we are at last index(end of the pathArr), we should write the input
    if (index === pathArr.length - 1) {
      level[path] = input;
    } else {
      level = level[path];
    }
    index++;
  }
}

const target = {};
pathToWriteTo(["/"], { omg: "333" }, target);
pathToWriteTo(["/", "omg"], { wow: "2323" }, target);

target.toEqual({
    "omg": {
        "wow": "2323"
    }
})