// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
 
#nullable disable
 
using System.Collections.Immutable;
using System.Reflection;
using System.Threading;
using Microsoft.CodeAnalysis.Host.Mef;
 
namespace AnalyzerRunner
{
    internal static class AnalyzerRunnerMefHostServices
    {
        private static MefHostServices s_defaultServices;
 
        public static MefHostServices DefaultServices
        {
            get
            {
                if (s_defaultServices is null)
                {
                    Interlocked.CompareExchange(ref s_defaultServices, MefHostServices.Create(DefaultAssemblies), null);
                }
 
                return s_defaultServices;
            }
        }
 
        private static ImmutableArray<Assembly> DefaultAssemblies
            => MSBuildMefHostServices.DefaultAssemblies.Add(typeof(AnalyzerRunnerMefHostServices).Assembly);
    }
}