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'use strict';
const isObject = value => typeof value === 'object' && value !== null;
const mapObjectSkip = Symbol('skip');
// Customized for this use-case
const isObjectCustom = value =>
isObject(value) &&
!(value instanceof RegExp) &&
!(value instanceof Error) &&
!(value instanceof Date);
const mapObject = (object, mapper, options, isSeen = new WeakMap()) => {
options = {
deep: false,
target: {},
...options
};
if (isSeen.has(object)) {
return isSeen.get(object);
}
isSeen.set(object, options.target);
const {target} = options;
delete options.target;
const mapArray = array => array.map(element => isObjectCustom(element) ? mapObject(element, mapper, options, isSeen) : element);
if (Array.isArray(object)) {
return mapArray(object);
}
for (const [key, value] of Object.entries(object)) {
const mapResult = mapper(key, value, object);
if (mapResult === mapObjectSkip) {
continue;
}
let [newKey, newValue, {shouldRecurse = true} = {}] = mapResult;
// Drop `__proto__` keys.
if (newKey === '__proto__') {
continue;
}
if (options.deep && shouldRecurse && isObjectCustom(newValue)) {
newValue = Array.isArray(newValue) ?
mapArray(newValue) :
mapObject(newValue, mapper, options, isSeen);
}
target[newKey] = newValue;
}
return target;
};
module.exports = (object, mapper, options) => {
if (!isObject(object)) {
throw new TypeError(`Expected an object, got \`${object}\` (${typeof object})`);
}
return mapObject(object, mapper, options);
};
module.exports.mapObjectSkip = mapObjectSkip;
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