// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
 
using System;
using System.Linq;
using Microsoft.Extensions.DependencyInjection;
using Xunit;
 
namespace Microsoft.Extensions.AsyncState.Test;
 
public class AsyncContextServiceCollectionExtensionsTests
{
    [Fact]
    public void AddAsyncStateCore_Throws_WhenNullService()
    {
        Assert.Throws<ArgumentNullException>(() => AsyncStateExtensions.AddAsyncState(null!));
    }
 
    [Fact]
    public void AddAsyncStateCore_AddsWithCorrectLifetime()
    {
        // Arrange
        var services = new ServiceCollection();
 
        // Act
        services.AddAsyncState();
 
        // Assert
        var serviceDescriptor = services.First(x => x.ServiceType == typeof(IAsyncContext<>));
        Assert.Equal(ServiceLifetime.Singleton, serviceDescriptor.Lifetime);
 
        serviceDescriptor = services.First(x => x.ServiceType == typeof(IAsyncState));
        Assert.Equal(ServiceLifetime.Singleton, serviceDescriptor.Lifetime);
 
        serviceDescriptor = services.First(x => x.ServiceType == typeof(IAsyncLocalContext<>));
        Assert.Equal(ServiceLifetime.Singleton, serviceDescriptor.Lifetime);
    }
}