Merge pull request #29 from BlaiseD/master

ArgumentException: "Argument types do not match" when mapping Conditional filters.

Author: BlaiseD

Directory.Build.props

@@ -2,7 +2,7 @@
   <PropertyGroup>
     <Authors>Jimmy Bogard</Authors>
     <LangVersion>latest</LangVersion>
-    <VersionPrefix>2.0.0</VersionPrefix>
+    <VersionPrefix>2.0.1-preview01</VersionPrefix>
     <WarningsAsErrors>true</WarningsAsErrors>
     <NoWarn>$(NoWarn);1701;1702;1591</NoWarn>
   </PropertyGroup>

src/AutoMapper.Extensions.ExpressionMapping/XpressionMapperVisitor.cs

@@ -130,6 +130,19 @@ Expression DoVisitBinary(Expression newLeft, Expression newRight, Expression con
             }
         }
 
+        protected override Expression VisitConditional(ConditionalExpression c)
+        {
+            return DoVisitConditional(this.Visit(c.Test), this.Visit(c.IfTrue), this.Visit(c.IfFalse));
+
+            Expression DoVisitConditional(Expression test, Expression ifTrue, Expression ifFalse)
+            {
+                if (test != c.Test || ifTrue != c.IfTrue || ifFalse != c.IfFalse)
+                    return Expression.Condition(test, ifTrue, ifFalse);
+
+                return c;
+            }
+        }
+
         protected override Expression VisitUnary(UnaryExpression node)
         {
             switch (node.NodeType)

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

@@ -176,6 +176,51 @@ public void Map__object_including_child_and_grandchild()
             Assert.True(users.Count == 2);
         }
 
+        [Fact]
+        public void Map__object_including_child_and_grandchild_with_conditional_filter()
+        {
+            //Arrange
+            ParameterExpression userParam = Expression.Parameter(typeof(UserModel), "s");
+            MemberExpression accountModelProperty = Expression.MakeMemberAccess(userParam, PrimitiveHelper.GetFieldOrProperty(typeof(UserModel), "AccountModel"));
+            MemberExpression branchModelProperty = Expression.MakeMemberAccess(accountModelProperty, PrimitiveHelper.GetFieldOrProperty(typeof(AccountModel), "Branch"));
+            MemberExpression nameProperty = Expression.MakeMemberAccess(branchModelProperty, PrimitiveHelper.GetFieldOrProperty(typeof(BranchModel), "Name"));
+
+            //{s => (IIF((IIF((s.AccountModel == null), null, s.AccountModel.Branch) == null), null, s.AccountModel.Branch.Name) == "Leeds")}
+            Expression<Func<UserModel, bool>> selection = Expression.Lambda<Func<UserModel, bool>>
+            (
+                Expression.Equal
+                (
+                    Expression.Condition
+                    (
+                        Expression.Equal
+                        (
+                            Expression.Condition
+                            (
+                                Expression.Equal
+                                (
+                                    accountModelProperty,
+                                    Expression.Constant(null, typeof(AccountModel))
+                                ),
+                                Expression.Constant(null, typeof(BranchModel)),
+                                branchModelProperty
+                            ),
+                            Expression.Constant(null, typeof(BranchModel))
+                        ),
+                        Expression.Constant(null, typeof(string)),
+                        nameProperty
+                    ),
+                    Expression.Constant("Park Row", typeof(string))
+                ),
+                userParam
+            );
+
+            Expression<Func<User, bool>> selectionMapped = mapper.Map<Expression<Func<User, bool>>>(selection);
+            List<User> users = Users.Where(selectionMapped).ToList();
+
+            //Assert
+            Assert.True(users.Count == 1);
+        }
+
         [Fact]
         public void Map_object_when_null_values_are_typed()
         {
@@ -783,6 +828,7 @@ public AccountModel()
         public string Description { get; set; }
         public string Type { get; set; }
         public DateTime DateCreated { get; set; }
+        public BranchModel Branch { get; set; }
         public ICollection<ThingModel> ThingModels { get; set; }
         public ICollection<UserModel> UserModels { get; set; }
     }
@@ -827,6 +873,12 @@ public class Branch
         public string Name { get; set; }
     }
 
+    public class BranchModel
+    {
+        public int Id { get; set; }
+        public string Name { get; set; }
+    }
+
     public class UserVM
     {
         public string Name { get; set; }