<PackageReference Include="Microsoft.Bcl.TimeProvider" Version="10.0.0-rc.2.25502.107" />

System.Threading.Tasks.TimeProviderTaskExtensions

public static class TimeProviderTaskExtensions
Provides extensions methods for Task operations with TimeProvider.
namespace System.Threading.Tasks { public static class TimeProviderTaskExtensions { public static Task Delay(this TimeProvider timeProvider, TimeSpan delay, CancellationToken cancellationToken = default(CancellationToken)); public static Task WaitAsync(this Task task, TimeSpan timeout, TimeProvider timeProvider, CancellationToken cancellationToken = default(CancellationToken)); public static Task<TResult> WaitAsync<[System.Runtime.CompilerServices.Nullable(2)] TResult>(this Task<TResult> task, TimeSpan timeout, TimeProvider timeProvider, CancellationToken cancellationToken = default(CancellationToken)); public static CancellationTokenSource CreateCancellationTokenSource(this TimeProvider timeProvider, TimeSpan delay); } }