Query inherited interfaces to find member #1182

FindInheritedInterfaceMember.cs

void Main()
{
	var interfaceType = typeof(IQueryableInterface);
	new[]{interfaceType}
		.RecursiveSelect(i=>i.GetTypeInfo().ImplementedInterfaces)
		.Distinct()
		.Select(i=>i.GetMember("PropertyInterface").FirstOrDefault())
		.FirstOrDefault(m=>m!=null)
		.Dump();
	typeof(IQueryableInterface).GetMember("PropertyInterface").Dump();
}

public interface IBaseBaseQueryableInterface
{
}

public interface IBaseQueryableInterface : IBaseBaseQueryableInterface
{
   IPropertyInterface PropertyInterface { get; set; }
}

public interface IQueryableInterface : IBaseQueryableInterface
{
   string AnotherProperty { get; set; }
}

public interface IPropertyInterface
{
   int PropertyInterfaceId { get; set; }
}

public class QueryableInterfaceImpl : IQueryableInterface
{
   public IPropertyInterface PropertyInterface { get; set; }
   public string AnotherProperty { get; set; }
}

public class PropertyInterfaceImpl : IPropertyInterface
{
   public int PropertyInterfaceId { get; set; }
}

public class QueryableDto
{
   public int PropertyInterfaceId { get; set; }
   public string AnotherProperty { get; set; }
}

public static class MyExtensions
{
   public static IEnumerable<TSource> RecursiveSelect<TSource>(this IEnumerable<TSource> source,
   Func<TSource, IEnumerable<TSource>> childSelector)
   {
      return RecursiveSelect(source, childSelector, element => element);
   }

   public static IEnumerable<TResult> RecursiveSelect<TSource, TResult>(this IEnumerable<TSource> source,
      Func<TSource, IEnumerable<TSource>> childSelector, Func<TSource, TResult> selector)
   {
      return RecursiveSelect(source, childSelector, (element, index, depth) => selector(element));
   }

   public static IEnumerable<TResult> RecursiveSelect<TSource, TResult>(this IEnumerable<TSource> source,
      Func<TSource, IEnumerable<TSource>> childSelector, Func<TSource, int, TResult> selector)
   {
      return RecursiveSelect(source, childSelector, (element, index, depth) => selector(element, index));
   }

   public static IEnumerable<TResult> RecursiveSelect<TSource, TResult>(this IEnumerable<TSource> source,
      Func<TSource, IEnumerable<TSource>> childSelector, Func<TSource, int, int, TResult> selector)
   {
      return RecursiveSelect(source, childSelector, selector, 0);
   }

   private static IEnumerable<TResult> RecursiveSelect<TSource, TResult>(this IEnumerable<TSource> source,
      Func<TSource, IEnumerable<TSource>> childSelector, Func<TSource, int, int, TResult> selector, int depth)
   {
      return source.SelectMany((element, index) => Enumerable.Repeat(selector(element, index, depth), 1)
         .Concat(RecursiveSelect(childSelector(element) ?? Enumerable.Empty<TSource>(),
            childSelector, selector, depth + 1)));
   }
}