Pass TestScriptsDoNotShareGlobals. Fixes issue #3036.

src/BizHawk.Client.Common/lua/ILuaLibraries.cs

@@ -48,7 +48,7 @@ namespace BizHawk.Client.Common
 
 		bool RemoveNamedFunctionMatching(Func<INamedLuaFunction, bool> predicate);
 
-		void SpawnAndSetFileThread(string pathToLoad, LuaFile lf);
+		void SpawnAndSetFileThread(LuaFile lf);
 
 		void ExecuteString(string command);
 
@@ -57,5 +57,7 @@ namespace BizHawk.Client.Common
 		void EnableLuaFile(LuaFile item);
 
 		void DisableLuaScript(LuaFile file);
+
+		Lua GetCurrentLua();
 	}
 }

src/BizHawk.Client.Common/lua/LuaLibrariesBase.cs

@@ -25,7 +25,7 @@ namespace BizHawk.Client.Common
 			Config config,
 			IGameInfo game)
 		{
-			_th = new NLuaTableHelper(_lua, LogToLuaConsole);
+			_th = new NLuaTableHelper(this, LogToLuaConsole);
 			_displayManager = displayManager;
 			_inputManager = inputManager;
 			_mainFormApi = mainFormApi;
@@ -36,38 +36,31 @@ namespace BizHawk.Client.Common
 			Docs.Clear();
 			_apiContainer = ApiManager.RestartLua(_mainFormApi.Emulator.ServiceProvider, LogToLuaConsole, _mainFormApi, _displayManager, _inputManager, _mainFormApi.MovieSession, _mainFormApi.Tools, config, _mainFormApi.Emulator, game);
 
-			var packageTable = (LuaTable) _lua["package"];
+			UpdatePackageTable(_luaWithoutFile);
-			var luaPath = PathEntries.LuaAbsolutePath();
-			if (OSTailoredCode.IsUnixHost)
-			{
-				// add %exe%/Lua to library resolution pathset (LUA_PATH)
-				// this is done already on windows, but not on linux it seems?
-				packageTable["path"] = $"{luaPath}/?.lua;{luaPath}?/init.lua;{packageTable["path"]}";
-				// we need to modifiy the cpath so it looks at our lua dir too, and remove the relative pathing
-				// we do this on Windows too, but keep in mind Linux uses .so and Windows use .dll
-				// TODO: Does the relative pathing issue Windows has also affect Linux? I'd assume so...
-				packageTable["cpath"] = $"{luaPath}/?.so;{luaPath}/loadall.so;{packageTable["cpath"]}";
-				packageTable["cpath"] = ((string)packageTable["cpath"]).Replace(";./?.so", "");
-			}
-			else
-			{
-				packageTable["cpath"] = $"{luaPath}\\?.dll;{luaPath}\\loadall.dll;{packageTable["cpath"]}";
-				packageTable["cpath"] = ((string)packageTable["cpath"]).Replace(";.\\?.dll", "");
-			}
 
-			_lua.RegisterFunction("print", this, typeof(LuaLibrariesBase).GetMethod(nameof(Print)));
+			_luaWithoutFile.RegisterFunction("print", this, typeof(LuaLibrariesBase).GetMethod(nameof(Print)));
 
-			RegisterLuaLibraries(Common.ReflectionCache.Types);
+			RegisterLuaLibraries(ReflectionCache.Types);
 		}
 
 		protected void EnumerateLuaFunctions(string name, Type type, LuaLibraryBase instance)
 		{
-			if (instance != null) _lua.NewTable(name);
+			if (instance != null)
+			{
+				_luaWithoutFile.NewTable(name);
+				_tablesForFunctions.Add(name);
+			}
 			foreach (var method in type.GetMethods())
 			{
 				var foundAttrs = method.GetCustomAttributes(typeof(LuaMethodAttribute), false);
 				if (foundAttrs.Length == 0) continue;
-				if (instance != null) _lua.RegisterFunction($"{name}.{((LuaMethodAttribute)foundAttrs[0]).Name}", instance, method);
+				if (instance != null)
+				{
+					string path = $"{name}.{((LuaMethodAttribute)foundAttrs[0]).Name}";
+					_luaWithoutFile.RegisterFunction(path, instance, method);
+					_functionsToRegister[path] = (instance, method);
+
+				}
 				LibraryFunction libFunc = new(
 					name,
 					type.GetCustomAttributes(typeof(DescriptionAttribute), false).Cast<DescriptionAttribute>()
@@ -109,6 +102,35 @@ namespace BizHawk.Client.Common
 			}
 		}
 
+		private void UpdatePackageTable(Lua lua)
+		{
+			var packageTable = (LuaTable)lua["package"];
+			var luaPath = PathEntries.LuaAbsolutePath();
+			if (OSTailoredCode.IsUnixHost)
+			{
+				// add %exe%/Lua to library resolution pathset (LUA_PATH)
+				// this is done already on windows, but not on linux it seems?
+				packageTable["path"] = $"{luaPath}/?.lua;{luaPath}?/init.lua;{packageTable["path"]}";
+				// we need to modifiy the cpath so it looks at our lua dir too, and remove the relative pathing
+				// we do this on Windows too, but keep in mind Linux uses .so and Windows use .dll
+				// TODO: Does the relative pathing issue Windows has also affect Linux? I'd assume so...
+				packageTable["cpath"] = $"{luaPath}/?.so;{luaPath}/loadall.so;{packageTable["cpath"]}";
+				packageTable["cpath"] = ((string)packageTable["cpath"]).Replace(";./?.so", "");
+			}
+			else
+			{
+				packageTable["cpath"] = $"{luaPath}\\?.dll;{luaPath}\\loadall.dll;{packageTable["cpath"]}";
+				packageTable["cpath"] = ((string)packageTable["cpath"]).Replace(";.\\?.dll", "");
+			}
+		}
+
+		private Dictionary<LuaFile, Lua> _activeLuas = new();
+
+		private Lua _luaWithoutFile = new();
+
+		private List<string> _tablesForFunctions = new();
+		private Dictionary<string, (LuaLibraryBase Lib, MethodInfo Func)> _functionsToRegister = new();
+
 		private ApiContainer _apiContainer;
 
 		private readonly DisplayManagerBase _displayManager;
@@ -119,9 +141,10 @@ namespace BizHawk.Client.Common
 
 		private readonly IMainFormForApi _mainFormApi;
 
-		private Lua _lua = new();
 		private LuaThread _currThread;
 
+		private Lua _currLua;
+
 		private readonly NLuaTableHelper _th;
 
 		protected Action<object[]> _logToLuaConsoleCallback = a => Console.WriteLine("a Lua lib is logging during init and the console lib hasn't been initialised yet");
@@ -167,13 +190,18 @@ namespace BizHawk.Client.Common
 
 		public LuaFunctionList RegisteredFunctions { get; }
 
+		public Lua GetCurrentLua()
+		{
+			return _currLua ?? _luaWithoutFile;
+		}
+
 		public void CallSaveStateEvent(string name)
 		{
 			try
 			{
 				foreach (var lf in RegisteredFunctions.Where(static l => l.Event == NamedLuaFunction.EVENT_TYPE_SAVESTATE).ToList())
 				{
-					lf.Call(name);
+					CallFunction(lf, name);
 				}
 			}
 			catch (Exception e)
@@ -190,7 +218,7 @@ namespace BizHawk.Client.Common
 			{
 				foreach (var lf in RegisteredFunctions.Where(static l => l.Event == NamedLuaFunction.EVENT_TYPE_LOADSTATE).ToList())
 				{
-					lf.Call(name);
+					CallFunction(lf, name);
 				}
 			}
 			catch (Exception e)
@@ -211,7 +239,7 @@ namespace BizHawk.Client.Common
 			{
 				foreach (var lf in RegisteredFunctions.Where(static l => l.Event == NamedLuaFunction.EVENT_TYPE_PREFRAME).ToList())
 				{
-					lf.Call();
+					CallFunction(lf);
 				}
 			}
 			catch (Exception e)
@@ -228,7 +256,7 @@ namespace BizHawk.Client.Common
 			{
 				foreach (var lf in RegisteredFunctions.Where(static l => l.Event == NamedLuaFunction.EVENT_TYPE_POSTFRAME).ToList())
 				{
-					lf.Call();
+					CallFunction(lf);
 				}
 			}
 			catch (Exception e)
@@ -246,7 +274,7 @@ namespace BizHawk.Client.Common
 					&& (l.LuaFile.Path == lf.Path || ReferenceEquals(l.LuaFile.Thread, lf.Thread)))
 				.ToList())
 			{
-				exitCallback.Call();
+				CallFunction(exitCallback);
 			}
 		}
 
@@ -256,7 +284,7 @@ namespace BizHawk.Client.Common
 				.Where(static l => l.Event == NamedLuaFunction.EVENT_TYPE_CONSOLECLOSE)
 				.ToList())
 			{
-				closeCallback.Call();
+				CallFunction(closeCallback);
 			}
 
 			RegisteredFunctions.Clear(_mainFormApi.Emulator);
@@ -268,8 +296,10 @@ namespace BizHawk.Client.Common
 					disposable.Dispose();
 			}
 
-			_lua.Dispose();
+			_luaWithoutFile.Dispose();
-			_lua = null;
+			_luaWithoutFile = null;
+			foreach (Lua lua in _activeLuas.Values)
+				lua.Dispose();
 		}
 
 		public INamedLuaFunction CreateAndRegisterNamedFunction(
@@ -280,7 +310,7 @@ namespace BizHawk.Client.Common
 			string name = null)
 		{
 			var nlf = new NamedLuaFunction(function, theEvent, logCallback, luaFile,
-				() => { _lua.NewThread(out var thread); return thread; }, name);
+				() => { _activeLuas[luaFile].NewThread(out var thread); return thread; }, name);
 			RegisteredFunctions.Add(nlf);
 			return nlf;
 		}
@@ -293,23 +323,48 @@ namespace BizHawk.Client.Common
 			return true;
 		}
 
-		public LuaThread SpawnCoroutine(string file)
+		public LuaThread SpawnCoroutine(LuaFile file)
 		{
-			var content = File.ReadAllText(file);
+			var content = File.ReadAllText(file.Path);
-			var main = _lua.LoadString(content, "main");
+			var main = _activeLuas[file].LoadString(content, "main");
-			_lua.NewThread(main, out var ret);
+			_activeLuas[file].NewThread(main, out var ret);
 			return ret;
 		}
 
-		public void SpawnAndSetFileThread(string pathToLoad, LuaFile lf)
+		public void SpawnAndSetFileThread(LuaFile lf)
-			=> lf.Thread = SpawnCoroutine(pathToLoad);
+		{ 
+			if (_activeLuas.ContainsKey(lf))
+				_activeLuas[lf].Dispose();
+
+			Lua lua = new();
+			UpdatePackageTable(lua);
+			lua.RegisterFunction("print", this, typeof(LuaLibrariesBase).GetMethod(nameof(Print)));
+			// We cannot copy tables from one Lua to another, unfortunately. Directly assigning them doesn't work at all.
+			// Transferring each individual value to new tables mostly works, but not always.
+			// For example event.onframeend would receive bad LuaFunction references.
+			foreach (string name in _tablesForFunctions)
+				lua.NewTable(name);
+			foreach (var item in _functionsToRegister)
+				lua.RegisterFunction(item.Key, item.Value.Lib, item.Value.Func);
+			_activeLuas[lf] = lua;
+
+			lf.Thread = SpawnCoroutine(lf);
+		}
 
 		public void ExecuteString(string command)
-			=> _lua.DoString(command);
+			=> _luaWithoutFile.DoString(command);
+
+		private void CallFunction(NamedLuaFunction func, string name = null)
+		{
+			_currLua = _activeLuas[func.LuaFile];
+			func.Call(name);
+			_currLua = null;
+		}
 
 		public (bool WaitForFrame, bool Terminated) ResumeScript(LuaFile lf)
 		{
 			_currThread = lf.Thread;
+			_currLua = _activeLuas[lf];
 
 			try
 			{
@@ -317,7 +372,6 @@ namespace BizHawk.Client.Common
 
 				var execResult = _currThread.Resume();
 
-				_currThread = null;
 				var result = execResult switch
 				{
 					LuaStatus.OK => (WaitForFrame: false, Terminated: true),
@@ -331,6 +385,8 @@ namespace BizHawk.Client.Common
 			finally
 			{
 				LuaLibraryBase.ClearCurrentThread();
+				_currThread = null;
+				_currLua = null;
 			}
 		}
 
@@ -368,7 +424,7 @@ namespace BizHawk.Client.Common
 		{
 			LuaSandbox.Sandbox(null, () =>
 			{
-				SpawnAndSetFileThread(item.Path, item);
+				SpawnAndSetFileThread(item);
 				LuaSandbox.CreateSandbox(item.Thread, Path.GetDirectoryName(item.Path));
 			}, () =>
 			{

src/BizHawk.Client.Common/lua/NLuaTableHelper.cs

@@ -14,6 +14,8 @@ namespace BizHawk.Client.Common
 	{
 		private readonly Action<string> _logCallback;
 
+		private readonly ILuaLibraries _luaLibraries;
+
 		private readonly Lua _lua;
 
 		public NLuaTableHelper(Lua lua, Action<string> logCallback)
@@ -22,7 +24,15 @@ namespace BizHawk.Client.Common
 			_lua = lua;
 		}
 
-		public LuaTable CreateTable() => _lua.NewTable();
+		public NLuaTableHelper(ILuaLibraries luaLibraries, Action<string> logCallback)
+		{
+			_logCallback = logCallback;
+			_luaLibraries = luaLibraries;
+		}
+
+		private Lua GetLua() => _luaLibraries?.GetCurrentLua() ?? _lua;
+
+		public LuaTable CreateTable() => GetLua().NewTable();
 
 		public LuaTable DictToTable<T>(IReadOnlyDictionary<string, T> dictionary)
 		{
@@ -60,7 +70,7 @@ namespace BizHawk.Client.Common
 			{
 				if (!method.IsPublic) continue;
 				var foundAttrs = method.GetCustomAttributes(typeof(LuaMethodAttribute), false);
-				table[method.Name] = _lua.RegisterFunction(
+				table[method.Name] = GetLua().RegisterFunction(
 					foundAttrs.Length == 0 ? string.Empty : ((LuaMethodAttribute) foundAttrs[0]).Name, // empty string will default to the actual method name
 					obj,
 					method

src/BizHawk.Client.Common/lua/NamedLuaFunction.cs

@@ -73,12 +73,8 @@ namespace BizHawk.Client.Common
 		public void DetachFromScript()
 		{
 			var thread = CreateThreadCallback();
-
+			LuaSandbox.CreateSandbox(thread, LuaFile.CurrentDirectory);
-			// Current dir will have to do for now, but this will inevitably not be desired
+			LuaFile.Thread = thread;
-			// Users will expect it to be the same directly as the thread that spawned this callback
-			// But how do we know what that directory was?
-			LuaSandbox.CreateSandbox(thread, ".");
-			LuaFile = new LuaFile(".") { Thread = thread };
 		}
 
 		public Guid Guid { get; }

src/BizHawk.Client.EmuHawk/tools/Lua/LuaConsole.cs

@@ -228,7 +228,7 @@ namespace BizHawk.Client.EmuHawk
 				{
 					LuaSandbox.Sandbox(file.Thread, () =>
 					{
-						LuaImp.SpawnAndSetFileThread(file.Path, file);
+						LuaImp.SpawnAndSetFileThread(file);
 						LuaSandbox.CreateSandbox(file.Thread, Path.GetDirectoryName(file.Path));
 						file.State = LuaFile.RunState.Running;
 					}, () =>