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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Soft reload throws in deserialization in a common workflow","articleBody":"### Environment\r\n\r\n-   Pythonnet version: current master (with soft reload).\r\n\r\nThis is in context of Unity Editor.\r\n\r\n### Details\r\n\r\n0. Use the soft-reload branch of pythonnet within Unity.\r\n1. Create an asmdef called MyAssembly in Unity.\r\n2. In the same folder, create a file Foo.cs\r\n```\r\nnamespace Foo\r\n{\r\n  public class Bar\r\n  {\r\n    public static void Quux() { UnityEngine.Debug.Log(\"quux\"); }\r\n  }\r\n}\r\n```\r\n3. In the Unity Python console:\r\n```\r\nimport clr\r\nclr.AddReference(\"MyAssembly\")\r\nimport Foo\r\nFoo.Bar.Quux()\r\n```\r\n4. This will print `quux` in the Unity console.\r\n5. In Unity, modify Foo.cs e.g. add a space in it.\r\n6. Allow Unity to reload the domain.\r\n7. This works!\r\n8. In Unity, modify Foo.cs and rename Quux to Quux2.\r\n\r\nExpected: Python for .NET is available after reload. Running Python code again will raise AttributeError.\r\n\r\nActual: Python for .NET throws `SerializationException: Cannot get the member 'Quux'.` I can't even run the Python code again; it fails on `import clr`. I must restart Unity.\r\n\r\nSimilarly if I rename the class, the namespace, or the assembly.\r\n\r\nThe problem appears to be in ManagedType subclasses. These are `[Serializable]` but they point to things like `Type` whose deserialization may fail, destroying everything.\r\n\r\nI'm working on a proof of concept so that we control the deserialization and we can replace the failed deserialize with a dummy or a `null`, which only fails if this eventually gets used. I'll post results tomorrow hopefully on a first attempt.","author":{"url":"https://github.com/benoithudson","@type":"Person","name":"benoithudson"},"datePublished":"2020-10-09T00:59:03.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":2},"url":"https://github.com/1250/pythonnet/issues/1250"}