René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"List conversion fails on new version of pythonnet compared to 3.0.0.post1","articleBody":"### Environment\r\n\r\n-   Pythonnet version:\r\nWorks with pythonnet==3.0.0.post1\r\nFailes with pythonnet\u003e=3.0.0.post1\r\n\r\n-   Python version:\r\nPython 3.8.0\r\n\r\n-   Operating System:\r\nWindows\r\n\r\n-   .NET Runtime:\r\nnetstandard2.0;net471\r\n\r\n### Details\r\n\r\nI followed the notes to write a codec to convert a C# List\u003cstrings\u003e to a Python list, here it is:\r\n\r\n ```\r\n   /// \u003csummary\u003e\r\n    /// This class will convert a C# list of strings to a Python list [] of strings.\r\n    /// \u003c/summary\u003e\r\n    public class ListStringConversions : IPyObjectEncoder\r\n    {\r\n        bool IPyObjectEncoder.CanEncode(Type type)\r\n        {\r\n            return type == typeof(IList\u003cstring\u003e);\r\n        }\r\n\r\n        PyObject IPyObjectEncoder.TryEncode(object value)\r\n        {\r\n            using (var scope = Py.CreateScope())\r\n            {\r\n                scope.Exec($\"a = []\");\r\n                var input = (List\u003cstring\u003e)value;\r\n                foreach (var item in input)\r\n                    scope.Exec($\"a.append('{item}')\");  // {item}\r\n                return scope.Get(\"a\");\r\n            }\r\n        }\r\n    }\r\n```\r\n\r\nI have a simple test which calls in to a C# assembly and returns a list. With pythonnet version 3.0.0.post1, the C# list is successfully converted to a python list.\r\n\r\nIn my requirements file, I had this\r\npythonnet\u003e=3.0.0.post1\r\n\r\nNow on the CICD process it has updated the pythonnet package and the same test fails:\r\n\r\n```\r\n\u003e       assert isinstance(codes, list)\r\nE       assert False\r\nE        +  where False = isinstance(\u003cSystem.Collections.Generic.IList[String] object at 0x0000023C1D9D5180\u003e, list)\r\n\r\n```\r\n\r\nThe code no longer is returning a python list. I switched the requirements file to \r\npythonnet==3.0.0.post1\r\n\r\nand the test passes. As such I think there is a breaking change in the latest release that prevents the conversions been executed.\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n\r\n","author":{"url":"https://github.com/screig","@type":"Person","name":"screig"},"datePublished":"2022-11-07T13:33:42.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":19},"url":"https://github.com/2004/pythonnet/issues/2004"}