NhQueryable.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Linq.Expressions;
using NHibernate.Engine;
using Remotion.Linq;

namespace NHibernate.Linq
{
	/// <summary>
	/// Interface to access the entity name of a NhQueryable instance.
	/// </summary>
	interface IEntityNameProvider
	{
		string EntityName { get; }
	}

	/// <summary>
	/// Provides the main entry point to a LINQ query.
	/// </summary>
	public class NhQueryable<T> : QueryableBase<T>, IEntityNameProvider, IEnumerable<T>
	{
		// This constructor is called by our users, create a new IQueryExecutor.
		public NhQueryable(ISessionImplementor session)
			: this(session, typeof(T).FullName)
		{
		}

		// This constructor is called by our users, create a new IQueryExecutor.
		public NhQueryable(ISessionImplementor session, string entityName)
			: base(QueryProviderFactory.CreateQueryProvider(session, null))
		{
			EntityName = entityName;
		}

		// This constructor is called indirectly by LINQ's query methods, just pass to base.
		public NhQueryable(IQueryProvider provider, Expression expression)
			: this(provider, expression, typeof(T).FullName)
		{
		}

		// This constructor is called indirectly by LINQ's query methods, just pass to base.
		public NhQueryable(IQueryProvider provider, Expression expression, string entityName)
			: base(provider, expression)
		{
			EntityName = entityName;
		}

		public NhQueryable(ISessionImplementor session, object collection)
			: base(QueryProviderFactory.CreateQueryProvider(session, collection))
		{
			EntityName = typeof(T).FullName;
		}

		public string EntityName { get; private set; }

		public override string ToString()
		{
			return "NHibernate.Linq.NhQueryable`1[" + EntityName + "]";
		}

		IEnumerator<T> IEnumerable<T>.GetEnumerator()
		{
			//TODO 6.0: Cast to INhQueryProvider
			return
				Provider is DefaultQueryProvider nhProvider
					? nhProvider.ExecuteList<T>(Expression).GetEnumerator()
					: base.GetEnumerator();
		}
	}
}