@tomhunter-gh can you try from the master?

pip install git+https://github.com/pythonnet/pythonnet -U --force

This should have been fixed recently:
#427

Hi @denfromufa

I pulled latest from master but I'm afraid I still get the problem. It looks like casting to a string[] array is successful, but the C# base class (and interface) are defined with a List<string> so I was expecting to be able to cast the dynamic back to a List<string>..

Were you able to reproduce the issue? What I did was I added the Interface1.cs, Class1.cs, Module.py to the Python.EmbeddingTest project. (By the way, in that project, any reason the 'fixtures' folder is not included in the project file?)

Thanks

@tomhunter-gh can you share your full project in a zip file? just paste it here to this issue.

fixtures are not included because it is python code, but could be included as a resource. we have a separate pyproj in the directory with python tests.

https://www.dropbox.com/s/0u4rbu5s2lr24b0/pythonnet.zip?dl=0

By the way I'm using Python 3.6 32-bit, so you may need to change settings in the Python.Runtime project file.

My test is in: pythonnet\src\embed_tests\pyimport.cs

Thanks

@tomhunter-gh actually that pull request which I linked above #427 leads to this issue :(

Here is the code that I commented out to pass your the test:

            /*if (value is IList && value.GetType().IsGenericType)
            {
                using (var resultlist = new PyList())
                {
                    foreach (object o in (IEnumerable)value)
                    {
                        using (var p = new PyObject(ToPython(o, o?.GetType())))
                        {
                            resultlist.Append(p);
                        }
                    }
                    Runtime.XIncref(resultlist.Handle);
                    return resultlist.Handle;
                }
            }*/

The reason is because before the list is passed back to C#, it gets converted to Python list.

So quick workaround would be to provide equivalent conversion from Python to C#: list -> List.

But this is of course a lot of conversion back and forth and maybe a performance issue.

This is rather hackish workaround, but passes all tests! Use at your own risk :)

pythonnet_hackish.zip

Thanks @denfromufa - that has fixed the issue!

Here's the change in case anyone else needs it:

(You also need to add a reference to Microsoft.CSharp.)

Thanks

related issue:

#514

I believe this should already be fixed in 3.0, but we need a test.