Avalonia/tests/Avalonia.Controls.UnitTests/EnumerableExtensions.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Avalonia.Controls.UnitTests
{
    internal static class EnumerableExtensions
    {
        public static IEnumerable<T> Do<T>(this IEnumerable<T> items, Action<T> action)
        {
            foreach (var i in items)
            {
                action(i);
                yield return i;
            }
        }
    }
}