let a = {
  'before': 'small',
  'after': 'large',
  'type': 'size'
};
 
let b = [
  {                     /*Esse objeto possui as mesmas propriedades com 
                          respectivos valores iguais ao objeto a, só que em ordem diferente*/
    'after': 'large',
    'before': 'small',
    'type': 'size'
  },
  {                    /*Esse objeto possui as mesmas propriedades porém com
                         respectivos valores diferentes ao objeto a*/
    'before': 'large',
    'after': 'small',
    'type': 'size'
  }
];
 
function findDiff(arr,obj){
   let diff=[]
   arr.forEach((Obj)=>{
     if(JSON.stringify(Obj)!=JSON.stringify(obj))diff.push(Obj)
   })
return diff
}
 
let diferentes=findDiff(b,a)
console.log("Resultado deveria ser 1 mas é %d", diferentes.length)

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