Add two tests for drawing with Lua scripts. One passes. TestDrawingWithTwoScripts fails.

src/BizHawk.Tests/BizHawk.Tests.csproj

@@ -16,6 +16,7 @@
 		<PackageReference Include="MSTest.TestFramework" Version="2.2.9" PrivateAssets="all" />
 		<PackageReference Include="JunitXml.TestLogger" Version="3.0.124" PrivateAssets="all" />
 		<ProjectReference Include="$(ProjectDir)../BizHawk.Client.Common/BizHawk.Client.Common.csproj" />
+		<ProjectReference Include="..\BizHawk.Bizware.Graphics\BizHawk.Bizware.Graphics.csproj" />
 		<Reference Include="NLua, Version=1.4.1.0, Culture=neutral, PublicKeyToken=null, processorArchitecture=MSIL" SpecificVersion="false" HintPath="$(ProjectDir)../../References/NLua.dll" Private="true" />
 		<None Include="$(ProjectDir)../../Assets/dll/lua54.dll" CopyToOutputDirectory="PreserveNewest" />
 		<!-- CHECKME: Does liblua5.4.so from a Linux host get picked up correctly? -->
@@ -25,4 +26,7 @@
 	<ItemGroup>
 		<EmbeddedResource Include="data/**/*" />
 	</ItemGroup>
+	<ItemGroup>
+		<Content Include="$(ProjectDir)/Client.Common/lua/LuaScripts/**" CopyToOutputDirectory="PreserveNewest" />
+	</ItemGroup>
 </Project>

src/BizHawk.Tests/Client.Common/lua/LuaScripts/DrawTest1.lua

@@ -0,0 +1,4 @@
+while true do
+	gui.drawRectangle(2, 2, 0, 0, 0xffff0000, 0, "client")
+	emu.frameadvance()
+end

src/BizHawk.Tests/Client.Common/lua/LuaScripts/DrawTest2.lua

@@ -0,0 +1,4 @@
+while true do
+	gui.drawRectangle(2, 4, 0, 0, 0xff00ff00, 0, "client")
+	emu.frameadvance()
+end

src/BizHawk.Tests/Client.Common/lua/TestLuaDrawing.cs

@@ -0,0 +1,78 @@
+using System.Drawing;
+using System.IO;
+
+using BizHawk.Bizware.BizwareGL;
+using BizHawk.Client.Common;
+using BizHawk.Emulation.Common;
+using BizHawk.Tests.Mocks;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+namespace BizHawk.Tests.Client.Common.Lua
+{
+	[TestClass]
+	public class TestLuaDrawing
+	{
+#pragma warning disable CS8625 // Cannot convert null literal to non-nullable reference type.
+		// null values are initialized in the setup method
+		private ILuaLibraries luaLibraries = null;
+		private DisplayManagerBase displayManager = null;
+#pragma warning restore CS8625 // Cannot convert null literal to non-nullable reference type.
+
+		private const string pathToTestLuaScripts = "Client.Common/lua/LuaScripts";
+
+		[TestInitialize]
+		public void TestSetup()
+		{
+			Config config = new Config();
+			IGameInfo gameInfo = new GameInfo();
+
+			IMainFormForApi mainForm = new MockMainFormForApi(new NullEmulator());
+			displayManager = new TestDisplayManager(mainForm.Emulator);
+
+			luaLibraries = new TestLuaLibraries(
+				mainForm,
+				displayManager,
+				config,
+				gameInfo
+			);
+			luaLibraries.Restart(config, gameInfo);
+		}
+
+		private LuaFile AddScript(string path, bool autoStart = true)
+		{
+			LuaFile luaFile = new LuaFile("", path);
+			luaLibraries.ScriptList.Add(luaFile);
+			luaLibraries.EnableLuaFile(luaFile);
+
+			if (autoStart)
+				luaLibraries.ResumeScript(luaFile);
+
+			return luaFile;
+		}
+
+		[TestMethod]
+		public void TestDrawingWithOneScript()
+		{
+			AddScript(Path.Combine(pathToTestLuaScripts, "DrawTest1.lua"));
+
+			BitmapBufferVideoProvider vp = new BitmapBufferVideoProvider(new BitmapBuffer(8, 8));
+			var buffer = displayManager.RenderOffscreenLua(vp);
+
+			Assert.AreEqual(buffer.GetPixel(2, 2), Color.Red.ToArgb());
+		}
+
+		[TestMethod]
+		public void TestDrawingWithTwoScripts()
+		{
+			AddScript(Path.Combine(pathToTestLuaScripts, "DrawTest1.lua"));
+			AddScript(Path.Combine(pathToTestLuaScripts, "DrawTest2.lua"));
+
+			BitmapBufferVideoProvider vp = new BitmapBufferVideoProvider(new BitmapBuffer(8, 8));
+			var buffer = displayManager.RenderOffscreenLua(vp);
+
+			Assert.AreEqual(buffer.GetPixel(2, 2), Color.Red.ToArgb());
+			Assert.AreEqual(buffer.GetPixel(2, 4), 0xff00ff00);
+		}
+
+	}
+}

src/BizHawk.Tests/Implementations/TestDisplayManager.cs

@@ -0,0 +1,31 @@
+using System.Drawing;
+
+using BizHawk.Bizware.Graphics;
+using BizHawk.Client.Common;
+using BizHawk.Emulation.Common;
+
+namespace BizHawk.Tests
+{
+	internal class TestDisplayManager : DisplayManagerBase
+	{
+		private Size _screenSize;
+
+		private TestDisplayManager(Config config, IEmulator emulator, InputManager inputManager, IGL_GDIPlus gl)
+			: base(config, emulator, inputManager, null, gl.DispMethodEnum, gl, new GDIPlusGuiRenderer(gl))
+		{
+			var vp = emulator.AsVideoProviderOrDefault();
+			_screenSize = new Size(vp.BufferWidth, vp.BufferHeight);
+
+		}
+		public TestDisplayManager(IEmulator emulator)
+			: this(new Config(), emulator, new InputManager(), new IGL_GDIPlus())
+		{ }
+
+		public override void ActivateOpenGLContext() { } // Nothing. We only use GDIPlus here.
+		public override Size GetPanelNativeSize() => _screenSize;
+		protected override void ActivateGraphicsControlContext() { }
+		protected override Size GetGraphicsControlSize() => _screenSize;
+		protected override Point GraphicsControlPointToClient(Point p) => p;
+		protected override void SwapBuffersOfGraphicsControl() { }
+	}
+}

src/BizHawk.Tests/Implementations/TestLuaLibraries.cs

@@ -0,0 +1,22 @@
+using System.Collections.Generic;
+
+using BizHawk.Client.Common;
+using BizHawk.Emulation.Common;
+
+namespace BizHawk.Tests
+{
+	internal class TestLuaLibraries : LuaLibrariesBase
+	{
+		public TestLuaLibraries(IMainFormForApi mainForm, DisplayManagerBase displayManager, Config config, IGameInfo game)
+			: base(new LuaFileList(
+				new List<LuaFile>(), () => { }),
+				  new LuaFunctionList(() => { }),
+				  mainForm,
+				  displayManager,
+				  new InputManager(),
+				  config,
+				  game
+			)
+		{ }
+	}
+}

src/BizHawk.Tests/Mocks/MockMainFormForApi.cs

@@ -0,0 +1,70 @@
+using System;
+using System.Drawing;
+
+using BizHawk.Client.Common;
+using BizHawk.Emulation.Common;
+
+namespace BizHawk.Tests.Mocks
+{
+	internal class MockMainFormForApi : IMainFormForApi
+	{
+		public (HttpCommunication HTTP, MemoryMappedFiles MMF, SocketServer Sockets) NetworkingHelpers => (null!, null!, null!);
+
+		public IEmulator Emulator { get; }
+
+		public IMovieSession MovieSession => null!;
+
+		public IToolManager Tools => null!;
+
+		public MockMainFormForApi(IEmulator emulator)
+		{
+			Emulator = emulator;
+		}
+
+
+		// Everything below here is not implemented.
+		public CheatCollection CheatList => throw new NotImplementedException();
+
+		public Point DesktopLocation => throw new NotImplementedException();
+
+		public bool EmulatorPaused => throw new NotImplementedException();
+
+		public bool InvisibleEmulation { get => throw new NotImplementedException(); set => throw new NotImplementedException(); }
+
+		public bool IsSeeking => throw new NotImplementedException();
+
+		public bool IsTurboing => throw new NotImplementedException();
+
+		public bool PauseAvi { get => throw new NotImplementedException(); set => throw new NotImplementedException(); }
+
+		public void ClearHolds() => throw new NotImplementedException();
+		public void ClickSpeedItem(int num) => throw new NotImplementedException();
+		public void CloseEmulator(int? exitCode = null) => throw new NotImplementedException();
+		public void CloseRom(bool clearSram = false) => throw new NotImplementedException();
+		public void EnableRewind(bool enabled) => throw new NotImplementedException();
+		public bool FlushSaveRAM(bool autosave = false) => throw new NotImplementedException();
+		public void FrameAdvance() => throw new NotImplementedException();
+		public void FrameBufferResized() => throw new NotImplementedException();
+		public void FrameSkipMessage() => throw new NotImplementedException();
+		public int GetApproxFramerate() => throw new NotImplementedException();
+		public bool LoadMovie(string filename, string? archive = null) => throw new NotImplementedException();
+		public bool LoadQuickSave(int slot, bool suppressOSD = false) => throw new NotImplementedException();
+		public bool LoadRom(string path, LoadRomArgs args) => throw new NotImplementedException();
+		public bool LoadState(string path, string userFriendlyStateName, bool suppressOSD = false) => throw new NotImplementedException();
+		public void PauseEmulator() => throw new NotImplementedException();
+		public bool RebootCore() => throw new NotImplementedException();
+		public void Render() => throw new NotImplementedException();
+		public bool RestartMovie() => throw new NotImplementedException();
+		public void SaveQuickSave(int slot, bool suppressOSD = false, bool fromLua = false) => throw new NotImplementedException();
+		public void SaveState(string path, string userFriendlyStateName, bool fromLua = false, bool suppressOSD = false) => throw new NotImplementedException();
+		public void SeekFrameAdvance() => throw new NotImplementedException();
+		public void StepRunLoop_Throttle() => throw new NotImplementedException();
+		public void StopMovie(bool saveChanges = true) => throw new NotImplementedException();
+		public void TakeScreenshot() => throw new NotImplementedException();
+		public void TakeScreenshot(string path) => throw new NotImplementedException();
+		public void TakeScreenshotToClipboard() => throw new NotImplementedException();
+		public void TogglePause() => throw new NotImplementedException();
+		public void ToggleSound() => throw new NotImplementedException();
+		public void UnpauseEmulator() => throw new NotImplementedException();
+	}
+}

src/BizHawk.Tests/PreTests.cs

@@ -0,0 +1,17 @@
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+namespace BizHawk.Tests
+{
+	[TestClass]
+	public class PreTests
+	{
+		[AssemblyInitialize]
+		public static void PreTestsMethod(TestContext context)
+		{
+			// This method will run only once, before all tests.
+			// So this seems a good place to initialize static classes.
+			BizHawk.Client.Common.ApiManager.FindApis(BizHawk.Client.Common.ReflectionCache.Types);
+		}
+	}
+
+}