private static bool NothingIsBeingMapped(MappingCreationContext context)
{
var mappingExpressions = context.GetMemberMappingExpressions();
if (mappingExpressions.None())
{
return(true);
}
if (mappingExpressions[0].NodeType != Assign)
{
return(false);
}
var assignedValue = ((BinaryExpression)mappingExpressions[0]).Right;
if (assignedValue.NodeType == Default)
{
return(true);
}
if (!mappingExpressions.HasOne())
{
return(false);
}
if (assignedValue == context.MapperData.TargetObject)
{
return(true);
}
if (assignedValue.NodeType != Coalesce)
{
return(false);
}
var valueCoalesce = (BinaryExpression)assignedValue;
if ((valueCoalesce.Left != context.MapperData.TargetObject) ||
(valueCoalesce.Right.NodeType != New))
{
return(false);
}
var objectNewing = (NewExpression)valueCoalesce.Right;
return(objectNewing.Arguments.None() && (objectNewing.Type != typeof(object)));
}
private static Expression GetMapToNullConditionOrNull(MappingCreationContext context)
{
if (context.MapperData.IsRoot || (context.MapToNullCondition != null))
{
return(context.MapToNullCondition);
}
var mappingExpressions = context.GetMemberMappingExpressions();
if (mappingExpressions.None())
{
return(null);
}
var memberAssignments = mappingExpressions
.Project(m =>
{
if (m.NodeType != Conditional)
{
return(m);
}
var conditionalMapping = (ConditionalExpression)m;
if (conditionalMapping.Test.IsNullableHasValueAccess() &&
(conditionalMapping.IfTrue.NodeType == Assign))
{
return(conditionalMapping.IfTrue);
}
return(m);
})
.Filter(m => m.NodeType == Assign)
.Cast <BinaryExpression>()
.Filter(a => a.Left.NodeType == MemberAccess)
.ToArray();
if (memberAssignments.Length != 1)
{
return(null);
}
var assignedMember = (MemberExpression)memberAssignments[0].Left;
var memberTypeIdentifier = context
.MapperContext
.GetIdentifierOrNull(assignedMember.Member.DeclaringType);
if (!Equals(assignedMember.Member, memberTypeIdentifier?.MemberInfo))
{
return(null);
}
var nonNullableIdType = assignedMember.Type.GetNonNullableType();
if ((nonNullableIdType == assignedMember.Type) || !nonNullableIdType.IsNumeric())
{
return(assignedMember.GetIsDefaultComparison());
}
return(Expression.Equal(
assignedMember.GetValueOrDefaultCall(),
0.ToConstantExpression(nonNullableIdType)));
}
private static bool NothingIsBeingMapped(MappingCreationContext context) => NothingIsBeingMapped(context.GetMemberMappingExpressions(), context);
