How to make extension only work on specific files

Hello, I added svelte extension (https://github.com/wewowweb/laravel-mix-svelte), but it triggers error as it scan all files, how to make it compile only specific files?

// Webpack.mix.js
// I want it compile only app.js, ignore super_campus.js
// Following doesn't work

mix.js('resources/js/pages/super_campus.js', 'public/js') .vue()

mix.js('resources/js/app.js', 'public/js').svelte();