find-cycles

Simple utility for finding cycles in objects.

Usage

import findCycles from 'find-cycles';

let obj = {};
obj.self = obj;

findCycles(obj);
// [['$'], ['$', 'self']]
// it means that one circular object was found
// and paths to it are: $ (root) and $.self

let a = {};
let b = {};
let c = {};
let d = {};
a.dep = b;
b.dep = c;
c.dep = a;
d.dep = d;

let obj = {a,b,c,d};

findCycles(b);
// [
//   ['$', 'a'], ['$', 'a', 'dep', 'dep', 'dep'],
//   ['$', 'd'], ['$', 'd', 'dep']
// ]
// it means that two circular objects were found
// and paths to them are:
//  * $.a and $.a.dep.dep.dep
//  * $.d and $.d.dep

If object has the same value for couple of properties but it's not circular, empty array is returned. Objects of type Number, String, Boolean, RegExp or Date are not taken into account too, it's because they do not cause circular structure error when serializing to JSON.

let obj = new Number(1);
obj.self = obj;

findCycles(obj); // []

let a = {};
let obj = {
  a1: a,
  a2: a
};

findCycles(obj); // []