respect [NonSerialized] when cloning

Author: lofcz

FastCloner.Tests/CopyToObjectTests.cs

@@ -271,7 +271,7 @@ public void TaskCancelledExceptionCloningTest()
 
         try
         {
-            // Create a cancelled task that will throw TaskCancelledException
+            // Create a canceled task that will throw TaskCancelledException
             cts.Cancel();
             Task.Delay(100, cts.Token).GetAwaiter().GetResult();
         }

FastCloner.Tests/SpecialCaseTests.cs

@@ -587,6 +587,14 @@ private class TestPropsWithIgnored
         [FastClonerIgnore]
         public string B { get; set; } = "My string";
     }
+    
+    private class TestPropsWithNonSerialized
+    {
+        public int A { get; set; } = 10;
+
+        [FastClonerIgnore]
+        public string B { get; set; } = "My string";
+    }
 
     [Test]
     public void Test_Clone_Props()
@@ -615,6 +623,20 @@ public void Test_Clone_Props_With_Ignored()
             Assert.That(clone, Is.Not.SameAs(original));
         });
     }
+    
+    [Test]
+    public void Test_Clone_Props_With_NonSerialized()
+    {
+        TestPropsWithNonSerialized original = new TestPropsWithNonSerialized { A = 42, B = "Test value" };
+        TestPropsWithNonSerialized clone = original.DeepClone();
+
+        Assert.Multiple(() =>
+        {
+            Assert.That(clone.A, Is.EqualTo(42));
+            Assert.That(clone.B, Is.EqualTo(null)); // default value
+            Assert.That(clone, Is.Not.SameAs(original));
+        });
+    }
 
     private class TestAutoProps
     {

FastCloner/Code/FastClonerExprGenerator.cs

@@ -31,8 +31,9 @@ private static bool MemberIsIgnored(MemberInfo memberInfo)
     {
         return FastClonerCache.GetOrAddMemberIgnoreStatus(memberInfo, mi =>
         {
-            FastClonerIgnoreAttribute? attribute = mi.GetCustomAttribute<FastClonerIgnoreAttribute>();
-            return attribute?.Ignored ?? false;
+            FastClonerIgnoreAttribute? fcIgnored = mi.GetCustomAttribute<FastClonerIgnoreAttribute>();
+            NonSerializedAttribute? nonSerialized = mi.GetCustomAttribute<NonSerializedAttribute>();
+            return fcIgnored?.Ignored ?? nonSerialized is not null;
         });
     }
 
@@ -193,17 +194,17 @@ private static void AddMemberCloneExpressions(
                 PropertyInfo pi => pi.PropertyType,
                 _ => throw new ArgumentException($"Unsupported member type: {member.GetType()}")
             };
-
-            bool isWritable = member switch
+            
+            bool canAssignDirect = member switch
             {
                 FieldInfo fi => !fi.IsInitOnly,
                 PropertyInfo pi => pi.CanWrite,
                 _ => false
-            } || type.IsClass() && member is FieldInfo { IsInitOnly: true };
+            };
 
             if (MemberIsIgnored(member))
             {
-                if (isWritable)
+                if (canAssignDirect)
                 {
                     expressionList.Add(Expression.Assign(
                         Expression.MakeMemberAccess(toLocal, member),
@@ -218,7 +219,7 @@ private static void AddMemberCloneExpressions(
             {
                 if (evtType == memberType)
                 {
-                    if (isWritable)
+                    if (canAssignDirect)
                     {
                         expressionList.Add(Expression.Assign(
                             Expression.MakeMemberAccess(toLocal, member),
@@ -232,7 +233,7 @@ private static void AddMemberCloneExpressions(
 
             if (FastClonerCache.IsTypeIgnored(memberType))
             {
-                if (isWritable)
+                if (canAssignDirect)
                 {
                     expressionList.Add(Expression.Assign(
                         Expression.MakeMemberAccess(toLocal, member),
@@ -245,7 +246,7 @@ private static void AddMemberCloneExpressions(
 
             if (member is PropertyInfo piLocal)
             {
-                if (isWritable && MemberIsIgnored(piLocal))
+                if (piLocal.CanWrite && MemberIsIgnored(piLocal))
                 {
                     expressionList.Add(Expression.Assign(
                         Expression.Property(toLocal, piLocal),
@@ -277,7 +278,7 @@ private static void AddMemberCloneExpressions(
 
                 if (shouldBeIgnored)
                 {
-                    if (member is FieldInfo or PropertyInfo { CanWrite: true })
+                    if (canAssignDirect)
                     {
                         expressionList.Add(Expression.Assign(
                             Expression.MakeMemberAccess(toLocal, member),

README.md

@@ -41,7 +41,7 @@ Sometimes, you might want to exclude certain fields (including event synthesized
 ```csharp
 private class TestPropsWithIgnored
 {
-    [FastClonerIgnore] // <-- decorate with [FastClonerIgnore]
+    [FastClonerIgnore] // <-- decorate with [FastClonerIgnore] or [NonSerialized]
     public string B { get; set; } = "My string";
 
     public int A { get; set; } = 10;