Cassette Extension to add multiple folders to a single bundle

gistfile1.cs

public static class BundleCollectionExtensions
{
    public static void AddMultipleDirectories<T>(this BundleCollection bundles, string appRelativePath, params string[] directories)
    where T : Bundle
    {
        var list = new List<string>();

        foreach (var dir in directories)
        {
            bundles.Add<T>(dir);
            var bundle = bundles.Get<T>(dir);
            bundles.Remove(bundle);

            list.AddRange(bundle.Assets.Select(a => a.Path));
        }

        bundles.Add<T>(appRelativePath, list);
    }
}