Remove duplicates on array of objects on Typescript

Remove duplicated elements on an array of objects can become complicated specially when having nested attributes or fields, we would need to do a deep compare to truly know if the element is repeated or not

To solve this issue we are going to use and npm module called just-diff this package will help us compare two objects and get the differences between both, this packages does a deep comparison, so it also works with nested attributes

First we are going to install the npm module using the following command

npm install just-diff

Now we are going to create a function that receives an array of objects and return an array without duplicates

import { diff } from "just-diff";

/**
 * @desc Receives and array of objects and remove duplicate elements
 * @param array array of objects
 */
export const removeArrayObjectsDuplicates = (array: any[]) => {
        // Array without duplicates that we are going to return
        const arrayWithoutDuplicates = [];

        // Loop through each element of array
        for (const element of array) {
            let duplicateFound = false;

            // Loop through each element on arrayWithoutDuplicates
            for (const elementWithoutDuplicates of arrayWithoutDuplicates) {
                const changes = diff(element, elementWithoutDuplicates);

                // If changes were not found change duplicatedFound to true
                if (changes.length === 0) {
                    duplicateFound = true;
                    break;
                }
            }

            // If no duplicated were found add element to arrayWithoutDuplicates
            if (!duplicateFound) {
                arrayWithoutDuplicates.push(element);
            }
        }

        return arrayWithoutDuplicates;
};

// Examples using the function above
const arrayWithDuplicates = [{ a: 1 }, { a: 1 }, { a: 15 }];
const secondArrayWithDuplicates = [{
    a: {
        b: 1,
        c: 2
    },
    d: [1, 2, 3]
},
    {
        a: {
            b: 1,
            c: 2
        },
        d: [1, 2, 4]
    }, {
        a: {
            b: 1,
            c: 2
        },
        d: [1, 2, 3]
    }, {
        a: {
            b: 4,
            c: 6
        },
        d: [2, 3, 4]
    }];


const firstResult = removeArrayObjectsDuplicates(arrayWithDuplicates);
// firstResult = [{"a":1},{"a":15}];
const secondResult = removeArrayObjectsDuplicates(secondArrayWithDuplicates);
// secondResult = [{"a":{"b":1,"c":2},"d":[1,2,3]},{"a":{"b":1,"c":2},"d":[1,2,4]},{"a":{"b":4,"c":6},"d":[2,3,4]}]