@cornerstonejs/core/dist/esm/utilities/deepMerge.js

Cornerstone3D Core

const isMergeableObject = (val) => {
    const nonNullObject = val && typeof val === 'object';
    return (nonNullObject &&
        Object.prototype.toString.call(val) !== '[object RegExp]' &&
        Object.prototype.toString.call(val) !== '[object Date]');
};
const emptyTarget = (val) => {
    const isEmpty = Array.isArray(val) ? [] : {};
    return isEmpty;
};
const cloneIfNecessary = (value, optionsArgument) => {
    const clone = optionsArgument && optionsArgument.clone === true;
    return clone && isMergeableObject(value)
        ? deepMerge(emptyTarget(value), value, optionsArgument)
        : value;
};
const defaultArrayMerge = (target, source, optionsArgument) => {
    const destination = target.slice();
    source.forEach(function (e, i) {
        if (typeof destination[i] === 'undefined') {
            destination[i] = cloneIfNecessary(e, optionsArgument);
        }
        else if (isMergeableObject(e)) {
            destination[i] = deepMerge(target[i], e, optionsArgument);
        }
        else if (target.indexOf(e) === -1) {
            destination[i] = cloneIfNecessary(e, optionsArgument);
        }
    });
    return destination;
};
const mergeObject = (target, source, optionsArgument) => {
    const destination = {};
    if (isMergeableObject(target)) {
        Object.keys(target).forEach(function (key) {
            destination[key] = cloneIfNecessary(target[key], optionsArgument);
        });
    }
    Object.keys(source).forEach(function (key) {
        if (!isMergeableObject(source[key]) || !target[key]) {
            destination[key] = cloneIfNecessary(source[key], optionsArgument);
        }
        else {
            destination[key] = deepMerge(target[key], source[key], optionsArgument);
        }
    });
    return destination;
};
const deepMerge = (target = {}, source = {}, optionsArgument = undefined) => {
    const array = Array.isArray(source);
    const options = optionsArgument || { arrayMerge: defaultArrayMerge };
    const arrayMerge = options.arrayMerge || defaultArrayMerge;
    if (array) {
        return Array.isArray(target)
            ? arrayMerge(target, source, optionsArgument)
            : cloneIfNecessary(source, optionsArgument);
    }
    return mergeObject(target, source, optionsArgument);
};
export default deepMerge;