Merge pull request #822 from DocSvartz/Fix-Nullable-Enum-Regression

Disabled NullableEnumFix #643  from MapToProjection cases

Author: DocSvartz

src/Mapster/Adapters/BaseAdapter.cs

@@ -479,7 +479,12 @@ protected Expression CreateAdaptExpression(Expression source, Type destinationTy
         }
         internal Expression CreateAdaptExpression(Expression source, Type destinationType, CompileArgument arg, MemberMapping? mapping, Expression? destination = null)
         {
-            var _source = source.NullableEnumExtractor(); // Extraction Nullable Enum
+            Expression _source;
+
+            if (arg.MapType != MapType.Projection)
+                _source = source.NullableEnumExtractor(); // Extraction Nullable Enum
+            else
+                _source = source;
 
             if (_source.Type == destinationType && arg.MapType == MapType.Projection)
                 return _source;