How to remove all blank Objects from an Object in Javascript?

Question

How to remove all blank Objects from an Object in Javascript? Like this

const test={a:'a',b:{},c:{c:{}}}

How to get result:

test={a:'a'}

Answer 1

The below recursive function will remove all empty objects.

function removeEmpty(obj) {
 Object.keys(obj).forEach(k => {
 if (obj[k] && typeof obj[k] === 'object' && removeEmpty(obj[k]) === null) {
 delete obj[k];
 }
 });
 if (!Object.keys(obj).length) {
 return null;
 }
}

Working Demo

function removeEmpty(obj) {
 Object.keys(obj).forEach(k => {
 if (obj[k] && typeof obj[k] === 'object' && removeEmpty(obj[k]) === null) {
 delete obj[k];
 }
 });
 if (!Object.keys(obj).length) {
 return null;
 }
}
const test1 = {data:{a:{}}};
removeEmpty(test1);
console.log(test1); // {}
const test2 = {data:{a:{}, b:1}};
removeEmpty(test2);
console.log(test2); // {data:{b: 1}}
const test3 = {a:'a',b:{},c:{c:{}}};
removeEmpty(test3);
console.log(test3); // {a: 'a'}

Answer 2

Here is another way with some details.

Needs/To keep in mind:

1. getting within obj implies looping
2. identify objects: avoid element not being object typed and only checks for object typed
3. going deeper: for nested objects, a recursive pattern is handy.
   ( careful to avoid infinite loop w/ recursive function execution )
4. delete/remove obj if empty

Code snippet:

 const test = {
 a: "a", b: {},
 c: { c: {} },
 d: {
 d: { e: {} }
 },
 }
 function checkObjEmptiness(obj) {
 // increases readability
 // avoid "typeof" checking as "typeof [] === 'object' // returns true"
 
 let isObject = (x) => x && x instanceof Object, 
 isEmpty = (x) => x && !Object.keys(x).length;
 // 1. loops over obj to check each elements emptiness
 for (let k in obj) {
 // 2. check for object within object based on: isObject && !isEmpty
 // 3. if object and not empty --> re-apply processus
 if (isObject(obj[k]) && !isEmpty(obj[k])) checkObjEmptiness(obj[k]);
 // handles deletion on obj if empty [ or value if empty ]
 //if (isEmpty(obj[k]) || !obj[k]) delete obj[k]; // handles empty values
 // 4. deletes object if empty
 if (isEmpty(obj[k])) delete obj[k]; //handles empty object
 }
 return obj;
 }
 checkObjEmptiness( test )