Function mergeConfigs

tests/test_code/js/moment/moment.js:372–399

(parentConfig, childConfig)

    }

    function mergeConfigs(parentConfig, childConfig) {
        var res = extend({}, parentConfig),
            prop;
        for (prop in childConfig) {
            if (hasOwnProp(childConfig, prop)) {
                if (isObject(parentConfig[prop]) && isObject(childConfig[prop])) {
                    res[prop] = {};
                    extend(res[prop], parentConfig[prop]);
                    extend(res[prop], childConfig[prop]);
                } else if (childConfig[prop] != null) {
                    res[prop] = childConfig[prop];
                } else {
                    delete res[prop];
                }
            }
        }
        for (prop in parentConfig) {
            if (
                hasOwnProp(parentConfig, prop) &&
                !hasOwnProp(childConfig, prop) &&
                isObject(parentConfig[prop])
            ) {
                // make sure changes to properties don't modify parent config
                res[prop] = extend({}, res[prop]);
            }
        }
        return res;
    }

    function Locale(config) {
        if (config != null) {