Use a Source Generator for ReflectionCache classes

ExternalProjects/BizHawk.SrcGen.ReflectionCache/BizHawk.SrcGen.ReflectionCache.csproj

@@ -0,0 +1,10 @@
+<Project Sdk="Microsoft.NET.Sdk">
+	<PropertyGroup>
+		<TargetFramework>netstandard2.0</TargetFramework>
+	</PropertyGroup>
+	<Import Project="../../Common.props" />
+	<ItemGroup>
+		<PackageReference Include="Microsoft.CodeAnalysis.Analyzers" Version="3.3.2" PrivateAssets="all" />
+		<PackageReference Include="Microsoft.CodeAnalysis.CSharp" Version="3.8.0" PrivateAssets="all" />
+	</ItemGroup>
+</Project>

ExternalProjects/BizHawk.SrcGen.ReflectionCache/ReflectionCacheGenerator.cs

@@ -0,0 +1,97 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Text;
+
+using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.CSharp.Syntax;
+using Microsoft.CodeAnalysis.Text;
+
+namespace BizHawk.SrcGen.ReflectionCache
+{
+	[Generator]
+	public sealed class ReflectionCacheGenerator : ISourceGenerator
+	{
+		private sealed class ReflectionCacheGenSyntaxReceiver : ISyntaxReceiver
+		{
+			/// <remarks>
+			/// I may have just added RNG to the build process...
+			/// Increase this sample size to decrease chance of random failure.
+			/// Alternatively, if you can come up with a better way of getting the project name in <see cref="ISourceGenerator.Execute"/> (I tried like 5 different things), do that instead.
+			/// --yoshi
+			/// </remarks>
+			private const int SAMPLE_SIZE = 20;
+
+			private string? _namespace;
+
+			private readonly List<string> _namespaces = new();
+
+			public string Namespace => _namespace ??= CalcNamespace();
+
+			private string CalcNamespace()
+			{
+				// black magic wizardry to find common prefix https://stackoverflow.com/a/35081977
+				var ns = new string(_namespaces.First()
+					.Substring(0, _namespaces.Min(s => s.Length))
+					.TakeWhile((c, i) => _namespaces.All(s => s[i] == c))
+					.ToArray());
+				return ns[ns.Length - 1] == '.' ? ns.Substring(0, ns.Length - 1) : ns; // trim trailing '.' (can't use BizHawk.Common from Source Generators)
+			}
+
+			public void OnVisitSyntaxNode(SyntaxNode syntaxNode)
+			{
+				static string Ser(NameSyntax nameSyn) => nameSyn switch
+				{
+					SimpleNameSyntax simple => simple.Identifier.ValueText,
+					QualifiedNameSyntax qual => $"{Ser(qual.Left)}.{Ser(qual.Right)}",
+					_ => throw new Exception()
+				};
+				if (_namespace != null || syntaxNode is not NamespaceDeclarationSyntax syn) return;
+				var newNS = Ser(syn.Name);
+				if (!newNS.StartsWith("BizHawk.")) return;
+				_namespaces.Add(newNS);
+				if (_namespaces.Count == SAMPLE_SIZE) _namespace = CalcNamespace();
+			}
+		}
+
+		public void Initialize(GeneratorInitializationContext context)
+			=> context.RegisterForSyntaxNotifications(() => new ReflectionCacheGenSyntaxReceiver());
+
+		public void Execute(GeneratorExecutionContext context)
+		{
+			if (context.SyntaxReceiver is not ReflectionCacheGenSyntaxReceiver receiver) return;
+			var nSpace = receiver.Namespace;
+			if (nSpace == null) return;
+			var extraImports = nSpace == "BizHawk.Common" ? string.Empty : "\nusing BizHawk.Common;";
+			var src = $@"#nullable enable
+
+using System;
+using System.IO;
+using System.Linq;
+using System.Reflection;
+{extraImports}
+
+namespace {nSpace}
+{{
+	public static class ReflectionCache
+	{{
+		private static readonly Assembly Asm = typeof({nSpace}.ReflectionCache).Assembly;
+
+		private static readonly Lazy<Type[]> _types = new Lazy<Type[]>(() => Asm.GetTypesWithoutLoadErrors().ToArray());
+
+		public static Type[] Types => _types.Value;
+
+		/// <exception cref=""ArgumentException"">not found</exception>
+		public static Stream EmbeddedResourceStream(string embedPath)
+		{{
+			var fullPath = $""{nSpace}.{{embedPath}}"";
+			return Asm.GetManifestResourceStream(fullPath) ?? throw new ArgumentException(""resource at {{fullPath}} not found"", nameof(embedPath));
+		}}
+	}}
+}}
+";
+			context.AddSource("ReflectionCache.cs", SourceText.From(src, Encoding.UTF8));
+		}
+	}
+}

src/BizHawk.Client.Common/ReflectionCache.cs

@@ -1,14 +0,0 @@
-using System;
-using System.Reflection;
-
-namespace BizHawk.Client.Common
-{
-	public static class ReflectionCache
-	{
-		private static readonly Lazy<Type[]> _types = new Lazy<Type[]>(() => Asm.GetTypes());
-
-		private static readonly Assembly Asm = typeof(ReflectionCache).Assembly;
-
-		public static Type[] Types => _types.Value;
-	}
-}

src/BizHawk.Client.EmuHawk/ReflectionCache.cs

@@ -1,20 +0,0 @@
-using System;
-using System.IO;
-using System.Linq;
-using System.Reflection;
-
-using BizHawk.Common;
-
-namespace BizHawk.Client.EmuHawk
-{
-	public static class ReflectionCache
-	{
-		private static readonly Lazy<Type[]> _types = new Lazy<Type[]>(() => Asm.GetTypesWithoutLoadErrors().ToArray());
-
-		private static readonly Assembly Asm = typeof(ReflectionCache).Assembly;
-
-		public static Type[] Types => _types.Value;
-
-		public static Stream EmbeddedResourceStream(string embedPath) => Asm.GetManifestResourceStream($"BizHawk.Client.EmuHawk.{embedPath}");
-	}
-}

src/BizHawk.Emulation.Common/ReflectionCache.cs

@@ -1,14 +0,0 @@
-using System;
-using System.Reflection;
-
-namespace BizHawk.Emulation.Common
-{
-	public static class ReflectionCache
-	{
-		private static readonly Lazy<Type[]> _types = new Lazy<Type[]>(() => Asm.GetTypes());
-
-		private static readonly Assembly Asm = typeof(ReflectionCache).Assembly;
-
-		public static Type[] Types => _types.Value;
-	}
-}

src/BizHawk.Emulation.Cores/ReflectionCache.cs

@@ -1,17 +0,0 @@
-using System;
-using System.IO;
-using System.Reflection;
-
-namespace BizHawk.Emulation.Cores
-{
-	public static class ReflectionCache
-	{
-		private static readonly Lazy<Type[]> _types = new Lazy<Type[]>(() => Asm.GetTypes());
-
-		private static readonly Assembly Asm = typeof(ReflectionCache).Assembly;
-
-		public static Type[] Types => _types.Value;
-
-		public static Stream EmbeddedResourceStream(string embedPath) => Asm.GetManifestResourceStream($"BizHawk.Emulation.Cores.{embedPath}");
-	}
-}

src/BizHawk.WinForms.Controls/BizHawk.WinForms.Controls.csproj

@@ -5,5 +5,6 @@
 	<Import Project="../MainSlnCommon.props" />
 	<ItemGroup>
 		<Reference Include="System.Windows.Forms" />
+		<ProjectReference Include="$(ProjectDir)../BizHawk.Common/BizHawk.Common.csproj" />
 	</ItemGroup>
 </Project>

src/MainSlnCommon.props

@@ -10,5 +10,6 @@
 	</PropertyGroup>
 	<ItemGroup>
 		<AdditionalFiles Include="$(ProjectDir)../../.stylecop.json" />
+		<ProjectReference Include="$(ProjectDir)../../ExternalProjects/BizHawk.SrcGen.ReflectionCache/BizHawk.SrcGen.ReflectionCache.csproj" OutputItemType="Analyzer" ReferenceOutputAssembly="false" />
 	</ItemGroup>
 </Project>