Object.getMaxDepth.js

// file "Object.getMaxDepth.js"

const Object = global.Object;

const object_prototype_toString = Object.prototype.toString;
const object_keys = Object.keys;

const math_max = global.Math.max;

const isArray = global.Array.isArray;
const isFiniteNumber = global.Number.isFinite;

function exposeInternalClassSignature (type) {
    return object_prototype_toString.call(type);
}

function isObject (type) {
    return (type && (typeof type === 'object'));
}

function isString (type) {
    return (/^\[object\s+String\]$/).test(exposeInternalClassSignature(type));
    // return ((typeof type === 'string') || (/^\[object\s+String\]$/).test(exposeInternalClassSignature(type)));
}

function isNumber (type) {
    return ((typeof type === 'number') || (/^\[object\s+Number\]$/).test(exposeInternalClassSignature(type)));
}
function isSafeNumber (type) {
    return (isNumber(type) && isFiniteNumber(type));
}

function getMaximumObjectLevelCount (type, count, maxCount) {
    if (!isObject(type)) {

        maxCount = (void 0);

    } else if (!isArray(type) && !isString(type)) {

        count = isSafeNumber(count) ? count : 0;
        maxCount = isSafeNumber(maxCount) ? maxCount : 0;

        const keyList = object_keys(type);
        let keyListIdx = keyList.length;

        if (keyListIdx >= 1) {
            ++count;

            while (keyListIdx--) {
                maxCount = math_max(count, getMaximumObjectLevelCount(type[keyList[keyListIdx]], count, maxCount));
            }
        }
    } else {

        maxCount = 0;
    }
    return maxCount;
}

export default (Object.getMaxDepth = getMaximumObjectLevelCount);

// const obj = {
//     level__1_A: {
//         level__1_A__2_A: {
//             level__1_A__2_A__3_A: 'level__1_A__2_A__3_A',
//             level__1_A__2_A__3_B: 'level__1_A__2_A__3_B',
//             level__1_A__2_A__3_C: {
//                 level__1_A__2_A__3_C__4_A: 'level__1_A__2_A__3_C__4_A',
//                 level__1_A__2_A__3_C__4_B: 'level__1_A__2_A__3_C__4_B',
//                 level__1_A__2_A__3_C__4_C: 'level__1_A__2_A__3_C__4_C'
//             },
//             level__1_A__2_A__3_D: 'level__1_A__2_A__3_D'
//         },
//         level__1_A__2_B: {
//             level__1_A__2_B__3_A: 'level__1_A__2_B__3_A',
//             level__1_A__2_B__3_B: 'level__1_A__2_B__3_B'
//         }
//     },
//     level__1_B: {
//         level__1_B__2_A: {
//             level__1_B__2_A__3_A: {
//                 level__1_B__2_A__3_A__4A: {
//                     level__1_B__2_A__3_A__4A__5A: 'level__1_B__2_A__3_A__4A__5A'
//                 },
//                 level__1_B__2_A__3_A__4B: 'level__1_B__2_A__3_A__4B'
//             },
//             level__1_B__2_A__3_B: 'level__1_B__2_A__3_B'
//         },
//         level__1_B__2_B: {
//             level__1_B__2_B__3_A: 'level__1_B__2_B__3_A',
//             level__1_B__2_B__3_B: 'level__1_B__2_B__3_B'
//         }
//     }
// };
//
// global.console.log('Object.getMaxDepth(obj) : ', Object.getMaxDepth(obj)); // 5