crazy.ts

describe('doit', () => {
  it('should build graph', () => {
    const t = {
      cart: ['saved'],
      saved: ['items'],
      items: []
    };

    const r = {
      cart: 'cart',
      saved: 'cart.saved',
      items: 'cart.saved.items'
    };

    const actual = doit(t);
    expect(actual).toEqual(r);
  });
  it('order should not matter', () => {
    const t = {
      saved: ['items'],
      items: [],
      cart: ['saved']
    };

    const r = {
      cart: 'cart',
      saved: 'cart.saved',
      items: 'cart.saved.items'
    };

    const actual = doit(t);
    expect(actual).toEqual(r);
  });
});

function findFullParentPath(obj, keyToFind) {
  for (const key in obj) {
    if (obj.hasOwnProperty(key) && obj[key].indexOf(keyToFind) >= 0) {
      const parent = findFullParentPath(obj, key);
      return parent !== null ? `${parent}.${key}` : key;
    }
  }
  return null;
}

function doit(obj, newObj = {}) {
  for (const key in obj) {
    if (obj.hasOwnProperty(key)) {
      const parent = findFullParentPath(obj, key);
      newObj[key] = parent ? `${parent}.${key}` : key;
    }
  }
  return newObj;
}