public static async Task <(NefFile nefFile, ContractManifest manifest)> LoadContractAsync(this IFileSystem fileSystem, string contractPath)
{
var nefTask = Task.Run(() =>
{
using var stream = fileSystem.File.OpenRead(contractPath);
using var reader = new System.IO.BinaryReader(stream, System.Text.Encoding.UTF8, false);
return(reader.ReadSerializable <NefFile>());
});
var manifestTask = fileSystem.File.ReadAllBytesAsync(fileSystem.Path.ChangeExtension(contractPath, ".manifest.json"))
.ContinueWith(t => ContractManifest.Parse(t.Result), default, TaskContinuationOptions.OnlyOnRanToCompletion, TaskScheduler.Default);