Added support for EF.Property method.

Author: sdanyliv

Source/LinqToDB.EntityFrameworkCore/LinqToDBForEFToolsImplDefault.cs

@@ -14,10 +14,10 @@
 using Microsoft.EntityFrameworkCore.Metadata;
 using Microsoft.EntityFrameworkCore.Query;
 using Microsoft.EntityFrameworkCore.Query.Internal;
+using Microsoft.EntityFrameworkCore.Query.ExpressionVisitors;
 using Microsoft.Extensions.Logging;
 
 using JetBrains.Annotations;
-using Microsoft.EntityFrameworkCore.Query.ExpressionVisitors;
 
 namespace LinqToDB.EntityFrameworkCore
 {
@@ -388,6 +388,12 @@ public virtual IDbContextOptions GetContextOptions(DbContext context)
 		static readonly MethodInfo AsNoTrackingMethodInfo =
 			MemberHelper.MethodOf<IQueryable<object>>(q => q.AsNoTracking()).GetGenericMethodDefinition();
 
+		static readonly MethodInfo EFProperty =
+			MemberHelper.MethodOf(() => EF.Property<object>(1, "")).GetGenericMethodDefinition();
+
+		private static readonly MethodInfo
+			L2DBProperty = typeof(Sql).GetMethod(nameof(Sql.Property)).GetGenericMethodDefinition();
+
 		public static Expression Unwrap(Expression ex)
 		{
 			if (ex == null)
@@ -657,14 +663,14 @@ Expression LocalTransform(Expression e)
 					case ExpressionType.Call:
 					{
 						var methodCall = (MethodCallExpression) e;
+						var generic = methodCall.Method.IsGenericMethod ? methodCall.Method.GetGenericMethodDefinition() : methodCall.Method;
 
 						if (IsQueryable(methodCall))
 						{
 							if (methodCall.Method.IsGenericMethod)
 							{
 								var isTunnel = false;
 
-								var generic = methodCall.Method.GetGenericMethodDefinition();
 								if (generic == IgnoreQueryFiltersMethodInfo)
 								{
 									ignoreQueryFilters = true;
@@ -705,6 +711,13 @@ Expression LocalTransform(Expression e)
 							}
 						}
 
+						if (generic == EFProperty)
+						{
+							var prop = Expression.Call(null, L2DBProperty.MakeGenericMethod(methodCall.Method.GetGenericArguments()[0]),
+								methodCall.Arguments[0].Transform(l => LocalTransform(l)), methodCall.Arguments[1]);
+							return prop;
+						}
+
 						break;
 					}
 				}

Tests/LinqToDB.EntityFrameworkCore.Tests/ToolsTests.cs

@@ -99,6 +99,20 @@ public void TestToList()
 			}
 		}
 
+		[Test]
+		public void TestShadowProperty()
+		{
+			using (var ctx = CreateAdventureWorksContext())
+			{
+				var query = ctx.Products.Select(p => new
+				{
+					Color = EF.Property<string>(p, "Color")
+				});
+
+				query = query.ToLinqToDB();
+				var result = query.ToArray();
+			}
+		}
 
 		[Test]
 		public void TestInsertFrom()