function magic_string_preprocessor_result(filename, src) {
	return {
		code: src.toString(),
		map: src.generateMap({
			source: path.basename(filename), // preprocessors are expected to return `sources: [file_basename]`
			hires: true,
			includeContent: false
		})
	};
}
@param {string} filename
@param {MagicString} src
@returns