Passing Arbitrary Arguments From C# to Lua Functions

Question

I have discovered the cause of the issue. An answer has been posted below.

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EDIT: The problem has changed, please see "The problem" section.

I am using LuaInterface. The generic call for lua functions using this library has this signature LuaFunction.Call(params object[] args). I have created a wrapper function that catches exceptions from the library and formats them for display on the in-game console window.

I am trying to call a lua function, but it is not receiving the arguments. This is the line in C#

Game.Instance.scriptEngine.Call("GenerateChunk", chunks[chunkID], GetChunkGridPosition(chunkID));

Which is simply wrapping a call to this Lua function that accepts two arguments:

//lua
function GenerateChunk(worldChunk, chunkGridPosition)
    Log(LogLevel.Error, worldChunk.ToString());
    Log(LogLevel.Error, chunkGridPosition.ToString());
end

that merely calls back into a C# Log function (which resolves correctly, and is visible in the Lua context).

The problem is that I am getting an "invalid arguments to method call" error from luainterface when attempting to call the GenerateChunk function, throwing this back:

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invalid arguments to method call
   at JASG.ScriptEngine.LuaError(Exception ex) Scripting\ScriptEngine.cs:line 144
   at JASG.ScriptEngine.Call(String fnName, Object[] args) Scripting\ScriptEngine.cs:line 86
   at JASG.ChunkManager.WakeChunk(Int32 chunkID) World\ChunkManager.cs:line 123
   at JASG.ChunkManager.GetChunk(Int32 chunkID, Boolean wakeIfAsleep) World\ChunkManager.cs:line 53

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I have tried various ways of calling the ScriptEngine.Call method, tried wrapping the arguments in an object[] array, etc., but no dice. Any ideas why lua is not receiving my arguments that I am passing? I have verified both arguments are non-null in C# when being passed in.

Answer 1

I incorrectly identified the problem as being with the call into Lua. The error message I was receiving was in fact originating from the Lua script calling back into my C# Log function.

I have discovered the hard way that in spite of exposing the enum LogManager.LogLevel to the lua script envronment, Lua does not support enum types. Thus,

Log(LogLevel.Debug, "hello"); 

was becoming

Log("Debug", "hello");

when marshalled by LuaInterface for the C# function. It was not until I created an ancillary ScriptLog(string level, string msg) that I was able to properly use the function from within lua. I wanted to keep the functionality of being able to use the enum names within Lua.

NOTE: As Lua does not support enum types, tonumber(LogLevel.Debug) fails as well.