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I have a function designed to sort / order / uniqify a given array.

Here is some of the code: Bubble Sort - 

function sort(postsCollection, type, direction){ let target = postsCollection[0][type]; let swapp = false, n = postsCollection[0].length - 1, x = postsCollection[0]; do { swapp = false; for(let i = 0; i < n; i++){ if(x[i][type] < x[i+1][type]){ x[i+1] = x[i]; swapp = true; } } n--; } while (swapp); return x; }

These exist in module.exports: 

 orderPostsCollection(postsCollection, sortType, direction, callback){ // Unique Array Creater let uniq = a => [...new Set(a)]; if(!sortType && !direction){ callback([...new Set(postsCollection)]); } if(sortType) { callback(sort([...new Set(postsCollection)], sortType, direction)); }else if(direction){ callback(sort([...new Set(postsCollection)], false, direction)); } }, uniqify(postsCollection, callback){ console.log([...new Set(postsCollection)]); callback([...new Set(postsCollection)]); }

it should make the data array unique. But it isn't..

Here is a sample:

{"posts":[{"author":"Rylee Paul","authorId":9,"id":1,"likes":960,"popularity":0.13,"reads":50361,"tags":["tech","health"]},{"author":"Zackery Turner","authorId":12,"id":2,"likes":469,"popularity":0.68,"reads":90406,"tags":["startups","tech","history"]},{"author":"Zackery Turner","authorId":12,"id":2,"likes":469,"popularity":0.68,"reads":90406,"tags":["startups","tech","history"]},{"author":"Zackery Turner","authorId":12,"id":2,"likes":469,"popularity":0.68,"reads":90406,"tags":["startups","tech","history"]},{"author":"Elisha Friedman","authorId":8,"id":13,"likes":230,"popularity":0.31,"reads":64058,"tags":["design","tech"]},{"author":"Elisha Friedman","authorId":8,"id":13,"likes":230,"popularity":0.31,"reads":64058,"tags":["design","tech"]},{"author":"Elisha Friedman","authorId":8,"id":13,"likes":230,"popularity":0.31,"reads":64058,"tags":["design","tech"]},{"author":"Elisha Friedman","authorId":8,"id":13,"likes":230,"popularity":0.31,"reads":64058,"tags":["design","tech"]},{"author":"Elisha Friedman","authorId":8,"id":13,"likes":230,"popularity":0.31,"reads":64058,"tags":["design","tech"]},{"author":"Elisha Friedman","authorId":8,"id":13,"likes":230,"popularity":0.31,"reads":64058,"tags":["design","tech"]},{"author":"Elisha Friedman","authorId":8,"id":13,"likes":230,"popularity":0.31,"reads":64058,"tags":["design","tech"]},{"author":"Elisha Friedman","authorId":8,"id":13,"likes":230,"popularity":0.31,"reads":64058,"tags":["design","tech"]},{"author":"Adalyn Blevins","authorId":11,"id":37,"likes":107,"popularity":0.55,"reads":35946,"tags":["tech","health","history"]},{"author":"Adalyn Blevins","authorId":11,"id":37,"likes":107,"popularity":0.55,"reads":35946,"tags":["tech","health","history"]},{"author":"Jon Abbott","authorId":4,"id":46,"likes":89,"popularity":0.96,"reads":79298,"tags":["culture","tech"]},{"author":"Jon Abbott","authorId":4,"id":46,"likes":89,"popularity":0.96,"reads":79298,"tags":["culture","tech"]},{"author":"Jon Abbott","authorId":4,"id":46,"likes":89,"popularity":0.96,"reads":79298,"tags":["culture","tech"]},{"author":"Jon Abbott","authorId":4,"id":46,"likes":89,"popularity":0.96,"reads":79298,"tags":["culture","tech"]},{"author":"Jon Abbott","authorId":4,"id":46,"likes":89,"popularity":0.96,"reads":79298,"tags":["culture","tech"]},{"author":"Jon Abbott","authorId":4,"id":46,"likes":89,"popularity":0.96,"reads":79298,"tags":["culture","tech"]},{"author":"Jon Abbott","authorId":4,"id":46,"likes":89,"popularity":0.96,"reads":79298,"tags":["culture","tech"]},{"author":"Jon Abbott","authorId":4,"id":46,"likes":89,"popularity":0.96,"reads":79298,"tags":["culture","tech"]},{"author":"Jon Abbott","authorId":4,"id":46,"likes":89,"popularity":0.96,"reads":79298,"tags":["culture","tech"]},{"author":"Bryson Bowers","authorId":6,"id":85,"likes":25,"popularity":0.18,"reads":16861,"tags":["tech"]},{"author":"Bryson Bowers","authorId":6,"id":85,"likes":25,"popularity":0.18,"reads":16861,"tags":["tech"]},{"author":"Bryson Bowers","authorId":6,"id":85,"likes":25,"popularity":0.18,"reads":16861,"tags":["tech"]},{"author":"Bryson Bowers","authorId":6,"id":85,"likes":25,"popularity":0.18,"reads":16861,"tags":["tech"]},{"author":"Bryson Bowers","authorId":6,"id":85,"likes":25,"popularity":0.18,"reads":16861,"tags":["tech"]}]}

why is this array is not made unique? what gives the above result?

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You're assuming [...new Set(data)] will filter out duplicate values – which is basically correct – but: Sets only filter out duplicates of primitive values (strings, numbers, booleans, etc.). Objects are not considered equal to each other even if they have the exact same content✝.

You could instead call your own uniqueFilter(postsCollection) function instead of using [...new Set(postsCollection)] that does filter objects based on the sameness of their content (see here for some examples).

✝ Objects are only considered "equal" to each other when they're literally references to the same object. e.g.

const a = {}; a === {}; // false const b = a; a === b; // true (because `b` is literally pointing to the exact same object as `a`)

Think of every object you make as having a secret key that always makes it unique regardless of its content.

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I recently discovered that [...new Set(arr)] does not remove objects since they are seen as Object:object

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