@geogirafe/lib-geoportal/tools/state/brain/equality.js

GeoGirafe is a flexible application to build online geoportals.

import { ignoreCloneSymbol } from './decorators';
/**
 * Returns true if the objects are deeply equal, false otherwise
 * Circular references are ignored
 */
export default function areEqual(obj1, obj2, visitedObjects = new WeakSet()) {
    obj1 = obj1?.__brainIsProxy ? obj1.__brainTarget : obj1;
    obj2 = obj2?.__brainIsProxy ? obj2.__brainTarget : obj2;
    // Same reference
    if (obj1 === obj2) {
        return true;
    }
    // Null & undefined
    if (obj1 === null || obj2 === null || obj1 === undefined || obj2 === undefined) {
        return obj1 === obj2;
    }
    // Already checked
    if (visitedObjects.has(obj1) && visitedObjects.has(obj2)) {
        return true;
    }
    // Primitives
    if (typeof obj1 !== 'object' || typeof obj2 !== 'object') {
        return obj1 === obj2;
    }
    // Dates
    if (obj1 instanceof Date && obj2 instanceof Date) {
        return obj1.getTime() === obj2.getTime();
    }
    // Mark the objects as visited
    visitedObjects.add(obj1);
    visitedObjects.add(obj2);
    // Arrays
    if (Array.isArray(obj1) && Array.isArray(obj2)) {
        return areArraysEqual(obj1, obj2, visitedObjects);
    }
    if (obj1 instanceof WeakMap ||
        obj2 instanceof WeakMap ||
        obj1 instanceof WeakSet ||
        obj2 instanceof WeakSet ||
        obj1 instanceof Map ||
        obj2 instanceof Map ||
        obj1 instanceof Set ||
        obj2 instanceof Set) {
        throw Error('Maps, Sets, WeakMaps and WeakSets deep comparison is not managed.');
    }
    // All other objects
    if (typeof obj1 === 'object' && typeof obj2 === 'object') {
        return areObjectsEqual(obj1, obj2, visitedObjects);
    }
    // Unmanaged case
    throw Error('Unmanaged case for equality check');
}
function areArraysEqual(obj1, obj2, visitedObjects) {
    if (obj1.length !== obj2.length) {
        // Different length for both arrays
        return false;
    }
    for (let i = 0; i < obj1.length; i++) {
        if (!areEqual(obj1[i], obj2[i], visitedObjects)) {
            // Not equal
            return false;
        }
    }
    // Arrays are equal
    return true;
}
function areObjectsEqual(obj1, obj2, visitedObjects) {
    // Ignore properties that begins with underscore and the ones that should not be cloned
    const keys1 = Object.keys(obj1).filter((key) => !key.startsWith('_') && !obj1[ignoreCloneSymbol]?.includes(key));
    const keys2 = Object.keys(obj2).filter((key) => !key.startsWith('_') && !obj2[ignoreCloneSymbol]?.includes(key));
    if (keys1.length !== keys2.length) {
        return false;
    }
    for (const key of keys1) {
        if (!obj2.hasOwnProperty(key)) {
            return false;
        }
        if (!areEqual(obj1[key], obj2[key], visitedObjects)) {
            return false;
        }
    }
    return true;
}