Fix for issue #8 (Source and destination must have same number of arg…

Directory.Build.props

@@ -2,7 +2,7 @@
   <PropertyGroup>
     <Authors>Jimmy Bogard</Authors>
     <LangVersion>latest</LangVersion>
-    <VersionPrefix>1.0.2</VersionPrefix>
+    <VersionPrefix>1.0.3</VersionPrefix>
     <WarningsAsErrors>true</WarningsAsErrors>
     <NoWarn>$(NoWarn);1701;1702;1591</NoWarn>
   </PropertyGroup>

src/AutoMapper.Extensions.ExpressionMapping/MapperExtensions.cs

@@ -290,7 +290,7 @@ void FindMaps(List<PropertyMap> maps)
             {
                 foreach (PropertyMap pm in maps)
                 {
-                    if (pm.SourceMember == null)
+                    if (!pm.SourceMembers.Any())
                         continue;
 
                     AddChildMappings

src/AutoMapper.Extensions.ExpressionMapping/XpressionMapperVisitor.cs

@@ -326,7 +326,7 @@ protected void FindDestinationFullName(Type typeSource, Type typeDestination, st
                     throw new InvalidOperationException(Resource.customResolversNotSupported);
                 }
 
-                if (propertyMap.CustomExpression == null && propertyMap.SourceMember == null)
+                if (propertyMap.CustomExpression == null && !propertyMap.SourceMembers.Any())
                     throw new InvalidOperationException(string.Format(CultureInfo.CurrentCulture, Resource.srcMemberCannotBeNullFormat, typeSource.Name, typeDestination.Name, sourceFullName));
 
                 CompareSourceAndDestLiterals
@@ -351,7 +351,7 @@ void CompareSourceAndDestLiterals(Type mappedPropertyType, string mappedProperty
                 var propertyMap = typeMap.GetPropertyMapByDestinationProperty(propertyName);
 
                 var sourceMemberInfo = typeSource.GetFieldOrProperty(propertyMap.DestinationProperty.Name);
-                if (propertyMap.CustomExpression == null && propertyMap.SourceMember == null)//If sourceFullName has a period then the SourceMember cannot be null.  The SourceMember is required to find the ProertyMap of its child object.
+                if (propertyMap.CustomExpression == null && !propertyMap.SourceMembers.Any())//If sourceFullName has a period then the SourceMember cannot be null.  The SourceMember is required to find the ProertyMap of its child object.
                     throw new InvalidOperationException(string.Format(CultureInfo.CurrentCulture, Resource.srcMemberCannotBeNullFormat, typeSource.Name, typeDestination.Name, propertyName));
 
                 propertyMapInfoList.Add(new PropertyMapInfo(propertyMap.CustomExpression, propertyMap.SourceMembers.ToList()));

tests/AutoMapper.Extensions.ExpressionMapping.UnitTests/XpressionMapperTests.cs

@@ -588,6 +588,19 @@ public void Test_Error_when_mapping_nested_expressions_when_enumerable_is_array_
             //Assert
             Assert.NotNull(expMapped);
         }
+
+        [Fact]
+        public void Can_correctly_type_maps_for_child_properties()
+        {
+            //Arrange
+            Expression<Func<OrderModel, bool>> src = x => x.Items.Any(i => i.Name == "Test");
+
+            //Act
+            Expression<Func<OrderEntity, bool>> dest = mapper.Map<Expression<Func<OrderEntity, bool>>>(src);
+
+            //Assert
+            Assert.NotNull(dest);
+        }
         #endregion Tests
 
         private static void SetupAutoMapper()
@@ -936,6 +949,31 @@ public class ChildDataClass
         public string Data { get; set; }
     }
 
+    class OrderModel
+    {
+        public IEnumerable<ItemModel> Items { get; set; }
+    }
+
+    class ItemModel
+    {
+        public string Name { get; set; }
+    }
+
+    class OrderEntity
+    {
+        public OrderData OrderData { get; set; }
+    }
+
+    class OrderData
+    {
+        public IEnumerable<ItemEntity> Items { get; set; }
+    }
+
+    class ItemEntity
+    {
+        public string Name { get; set; }
+    }
+
     public class OrganizationProfile : Profile
     {
         public OrganizationProfile()
@@ -1024,6 +1062,10 @@ public OrganizationProfile()
                 .ReverseMap()
                 .ForMember(d => d.ID, opt => opt.MapFrom(s => s.ID_));
 
+            CreateMap<OrderEntity, OrderModel>()
+                    .ForMember(x => x.Items, opt => opt.MapFrom(x => x.OrderData.Items));
+            CreateMap<ItemEntity, ItemModel>();
+
             CreateMissingTypeMaps = true;
         }
     }