Update method when properties are not readonly

src/MapTo/MappingContext.cs

@@ -137,6 +137,8 @@ namespace MapTo
                 return null;
             }
 
+           
+
             string? converterFullyQualifiedName = null;
             var converterParameters = ImmutableArray<string>.Empty;
             ITypeSymbol? mappedSourcePropertyType = null;
@@ -162,7 +164,9 @@ namespace MapTo
                 converterParameters.ToImmutableArray(),
                 sourceProperty.Name,
                 ToQualifiedDisplayName(mappedSourcePropertyType),
-                ToQualifiedDisplayName(enumerableTypeArgumentType));
+                ToQualifiedDisplayName(enumerableTypeArgumentType),
+               (sourceProperty as IPropertySymbol).IsReadOnly);
+;
         }
 
         protected bool TryGetMapTypeConverter(ISymbol property, IPropertySymbol sourceProperty, out string? converterFullyQualifiedName,

src/MapTo/Models.cs

@@ -29,7 +29,8 @@ namespace MapTo
         ImmutableArray<string> TypeConverterParameters,
         string SourcePropertyName,
         string? MappedSourcePropertyTypeName,
-        string? EnumerableTypeArgument)
+        string? EnumerableTypeArgument,
+        bool isReadOnly)
     {
         public bool IsEnumerable => EnumerableTypeArgument is not null;
     }

src/MapTo/Sources/MapClassSource.cs

@@ -31,7 +31,14 @@ namespace MapTo.Sources
 
             builder
                 .GeneratePrivateConstructor(model)
-                    .WriteLine()
+                .WriteLine();
+
+            if(PropertiesAreReadOnly(model))
+            {
+                builder.GenerateUpdateMethod(model);
+            }
+
+            builder
                     //.GenerateFactoryMethod(model)
                     .GenerateUpdateMethod(model)
 
@@ -105,7 +112,7 @@ namespace MapTo.Sources
                     {
                         builder.WriteLine(property.MappedSourcePropertyTypeName is null
                             ? $"{property.Name} = {sourceClassParameterName}.{property.SourcePropertyName};"
-                            : $"{property.Name} = {mappingContextParameterName}.{MappingContextSource.MapMethodName}<{property.MappedSourcePropertyTypeName}, {property.Type}>({sourceClassParameterName}.{property.SourcePropertyName});");
+                            : "");
                     }
                 }
                 else
@@ -123,6 +130,16 @@ namespace MapTo.Sources
 
         }
 
+        private static bool PropertiesAreReadOnly(MappingModel model)
+        {
+            foreach (var property in model.MappedProperties)
+            {
+                if (!property.isReadOnly) return false;
+            }
+            return true ;
+
+        }
+
         private static SourceBuilder GenerateFactoryMethod(this SourceBuilder builder, MappingModel model)
         {
             var sourceClassParameterName = model.SourceTypeIdentifierName.ToCamelCase();