Try read LuaValue

[ashtonmeuser]

Return the original ref when calling LuaValue.TryRead<LuaValue>. This is useful for generics where T may be LuaValue.

For example, the consider the following readonly LuaTable that reads from a backing IReadOnlyDictionary<TKey, TValue>. This works as is in all cases except when the key or value type is LuaValue itself.

public static LuaTable ReadOnlyDict<TKey, TValue>(IReadOnlyDictionary<TKey, TValue> backing)
{
    var proxy = new LuaTable();
    var metatable = new LuaTable();

    metatable[Metamethods.Index] = new LuaFunction("__index", (context, ct) =>
    {
        var keyValue = context.GetArgument(1);
        if (!keyValue.TryRead<TKey>(out var key) || !backing.TryGetValue(key, out var value))
            return new(context.Return(LuaValue.Nil));

        return new(context.Return(LuaValue.FromObject(value)));
    });

    metatable[Metamethods.NewIndex] = new LuaFunction("__newindex", (context, ct) =>
        throw new LuaRuntimeException(context.State, $"readonly table: cannot assign key '{context.GetArgument(1)}'"));

    metatable[Metamethods.Metatable] = "readonly";
    proxy.Metatable = metatable;

    return proxy;
}

P.S. I intend to make a PR with some of the collection wrappers I've created like the one above.

[Copilot]

Pull request overview

Updates LuaValue.TryRead<T> so that requesting T == LuaValue succeeds and returns the original LuaValue instance, enabling generic code paths where T may itself be LuaValue.

Changes:

• Add a fast-path in LuaValue.TryRead<T> for T == LuaValue that returns this without conversion.
• Add tests covering TryRead<LuaValue> (including Nil), Read<LuaValue>, and reference preservation for TryRead<LuaTable>.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
src/Lua/LuaValue.cs	Adds T == LuaValue special-case in TryRead<T> to return the original value.
tests/Lua.Tests/LuaValueTests.cs	Adds unit tests validating the new TryRead/Read behavior and table identity behavior.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[akeit0]

Merged! Thanks!