enableSassLoader(sassLoaderOptionsCallback = () => {}, options = {}) {
        this.useSassLoader = true;

        if (typeof sassLoaderOptionsCallback !== 'function') {
            throw new Error('Argument 1 to enableSassLoader() must be a callback function.');
        }

        this.sassLoaderOptionsCallback = sassLoaderOptionsCallback;

        for (const optionKey of Object.keys(options)) {
            if (!(optionKey in this.sassOptions)) {
                throw new Error(`Invalid option "${optionKey}" passed to enableSassLoader(). Valid keys are ${Object.keys(this.sassOptions).join(', ')}`);
            }

            this.sassOptions[optionKey] = options[optionKey];
        }
    }
@param {OptionsCallback<object>} sassLoaderOptionsCallback
@param {{resolveUrlLoader?: boolean, resolveUrlLoaderOptions?: object}} options