Demonstrates the simple extension method required to enable the C# 5 await keyword for MSBuild builds

MSBuildAwaiterSample.cs

namespace MSBuildAwaiterSample
{
    using System.Threading.Tasks;
    using Microsoft.Build.Execution;

    class Program
    {
        static void Main(string[] args)
        {

        }

        internal static async Task<BuildResult> Build(BuildManager buildManager, BuildParameters parameters, BuildRequestData data)
        {
            buildManager.BeginBuild(parameters);
            BuildSubmission submission = buildManager.PendBuildRequest(data);
            BuildResult buildResult = await submission.ExecuteAsync();
            buildManager.EndBuild();
            return buildResult;
        }
    }

    public static class BuildSubmissionAwaitExtensions
    {
        public static Task<BuildResult> ExecuteAsync(this BuildSubmission submission)
        {
            var tcs = new TaskCompletionSource<BuildResult>();
            submission.ExecuteAsync(SetBuildComplete, tcs);
            return tcs.Task;
        }

        private static void SetBuildComplete(BuildSubmission submission)
        {
            var tcs = (TaskCompletionSource<BuildResult>)submission.AsyncContext;
            tcs.SetResult(submission.BuildResult);
        }
    }
}