Fixing caching of complex type ctor parameter construction expressions / Using hash code comparers in member caches

Author: SteveWilkes

AgileMapper.UnitTests/Configuration/WhenConfiguringObjectCreation.cs

@@ -122,6 +122,7 @@ public void ShouldUseAConfiguredSingleParameterFactoryFuncForASpecifiedSourceTar
                 nonMatchingSourceResult.Address.Line2.ShouldBeNull();
 
                 var nonMatchingTargetResult = mapper.Map(matchingSource).ToANew<Person>();
+
                 // The declared target type doesn't match, but CustomerViewModel is automatically 
                 // mapped to Customer because of the matching naming conventions:
                 nonMatchingTargetResult.Address.Line2.ShouldBe("Frankie House");

AgileMapper/Api/Configuration/CustomDataSourceTargetMemberSpecifier.cs

@@ -266,14 +266,8 @@ private static Exception AmbiguousParameterException(string parameterMatchInfo)
 
         private ConfiguredDataSourceFactory CreateForCtorParam<TParam>(ParameterInfo parameter)
         {
-            var memberChain = new[]
-            {
-                Member.RootTarget<TTarget>(),
-                Member.ConstructorParameter(parameter)
-            };
-
             var valueLambda = GetValueLambdaInfo<TParam>();
-            var constructorParameter = QualifiedMember.From(memberChain, _configInfo.MapperContext);
+            var constructorParameter = CreateRootTargetQualifiedMember().Append(Member.ConstructorParameter(parameter));
 
             return new ConfiguredDataSourceFactory(_configInfo, valueLambda, constructorParameter);
         }

AgileMapper/Members/ConfiguredSourceMember.cs

@@ -81,7 +81,8 @@ private ConfiguredSourceMember(
                     : type.GetEnumerableElementType();
             }
 
-            _childMemberCache = mapperContext.Cache.CreateNew<Member, ConfiguredSourceMember>();
+            _childMemberCache = mapperContext.Cache.CreateNew<Member, ConfiguredSourceMember>(
+                default(HashCodeComparer<Member>));
         }
 
         public bool IsRoot => false;

AgileMapper/Members/Member.cs

@@ -244,6 +244,8 @@ private static class TargetMemberCache<T>
 
         public bool Equals(Member otherMember) => otherMember._hashCode == _hashCode;
 
+        public override int GetHashCode() => _hashCode;
+
         #region ExcludeFromCodeCoverage
 #if DEBUG
         [ExcludeFromCodeCoverage]

AgileMapper/Members/MemberExtensions.cs

@@ -199,7 +199,7 @@ public static Member[] RelativeTo(this Member[] memberChain, Member[] otherMembe
             var startIndex = memberChain.Length - 1;
 
             if ((memberChain.Length > 2) &&
-                memberChain[startIndex] == memberChain[startIndex - 1])
+                 memberChain[startIndex] == memberChain[startIndex - 1])
             {
                 // The member chain ends in a 1-to-1, immediately recursive
                 // relationship; skip the last element:
@@ -210,7 +210,7 @@ public static Member[] RelativeTo(this Member[] memberChain, Member[] otherMembe
             {
                 var member = memberChain[startIndex];
 
-                if (member == otherMembersLeafMember)
+                if (member.Equals(otherMembersLeafMember))
                 {
                     break;
                 }

AgileMapper/Members/QualifiedMember.cs

@@ -81,7 +81,7 @@ private QualifiedMember(Member leafMember, MapperContext mapperContext)
 
             if (!IsSimple)
             {
-                _childMemberCache = mapperContext.Cache.CreateNew<Member, QualifiedMember>();
+                _childMemberCache = mapperContext.Cache.CreateNew<Member, QualifiedMember>(default(HashCodeComparer<Member>));
             }
 
             RegistrationName = (LeafMember.MemberType != MemberType.ConstructorParameter)

AgileMapper/ObjectPopulation/ComplexTypes/ComplexTypeConstructionFactory.cs

@@ -361,11 +361,11 @@ public void AddTo(IList<Construction> constructions, ConstructionKey key)
             {
                 if (ParameterCount > 0)
                 {
-                    foreach (var memberAndDataSourceSet in _argumentDataSources)
+                    var dataSources = key.MappingData.MapperData.DataSourcesByTargetMember;
+
+                    foreach (var memberAndDataSourceSet in _argumentDataSources.Filter(ads => !dataSources.ContainsKey(ads.Item1)))
                     {
-                        key.MappingData.MapperData.DataSourcesByTargetMember.Add(
-                            memberAndDataSourceSet.Item1,
-                            memberAndDataSourceSet.Item2);
+                        dataSources.Add(memberAndDataSourceSet.Item1, memberAndDataSourceSet.Item2);
                     }
                 }