From 808cef9a1059fcf1a66d4b105a40106a7d463017 Mon Sep 17 00:00:00 2001
From: Yuriy Zatuchnyy <yzdeveloper@yahoo.com>
Date: Wed, 14 Feb 2024 20:27:43 +0000
Subject: [PATCH] Analyzers/AnalyzerScope loops endlessly when analysing public
 inner class

---
 ILSpy.Tests/Analyzers/AnalyserScopeTests.cs | 52 +++++++++++++++++++++
 ILSpy.Tests/ILSpy.Tests.csproj              |  1 +
 ILSpy/Analyzers/AnalyzerScope.cs            |  2 +-
 3 files changed, 54 insertions(+), 1 deletion(-)
 create mode 100644 ILSpy.Tests/Analyzers/AnalyserScopeTests.cs

diff --git a/ILSpy.Tests/Analyzers/AnalyserScopeTests.cs b/ILSpy.Tests/Analyzers/AnalyserScopeTests.cs
new file mode 100644
index 00000000000..736e730d26f
--- /dev/null
+++ b/ILSpy.Tests/Analyzers/AnalyserScopeTests.cs
@@ -0,0 +1,52 @@
+using System.Linq;
+using System.Threading.Tasks;
+
+using ICSharpCode.Decompiler;
+using ICSharpCode.Decompiler.CSharp.Resolver;
+using ICSharpCode.Decompiler.Metadata;
+using ICSharpCode.Decompiler.TypeSystem;
+using ICSharpCode.ILSpy.Analyzers;
+
+using Mono.Cecil;
+
+using NUnit.Framework;
+
+namespace ICSharpCode.ILSpy.Tests.Analyzers
+{
+
+	[TestFixture]
+	public class AnalyzerScopeTests
+	{
+		public class TestClass
+		{
+
+		}
+
+
+		[Test]
+		public void WhenPublicNestedClass_ThenNotInfiniteLoop()
+		{
+			// Given
+			ILSpyX.AssemblyList assemblyList = new ILSpyX.AssemblyList();
+			var file = new PEFile(this.GetType().Assembly.Location);
+			var td = file.Metadata.TypeDefinitions.First(td => td.GetFullTypeName(file.Metadata).Name == nameof(TestClass));
+
+			Decompiler.Metadata.IAssemblyResolver assemblyResolver = new UniversalAssemblyResolver(null, false, null);
+			ICompilation compilation = new DecompilerTypeSystem(file, assemblyResolver);
+			ITypeResolveContext context = new CSharpResolver(compilation);
+			var module = ((IModuleReference)file).Resolve(context) as MetadataModule;
+			IEntity entity = module.GetDefinition(td);
+
+			// When 
+			var task = Task.Run(() => {
+				var target = new AnalyzerScope(assemblyList, entity);
+			});
+
+			var result = Task.WaitAny(new[] { task, Task.Delay(500) }); // 0.5 seconds
+
+			// Then
+			Assert.That(result == 0, "The constructor should completes in no longer than 10 seconds");
+		}
+
+	}
+}
diff --git a/ILSpy.Tests/ILSpy.Tests.csproj b/ILSpy.Tests/ILSpy.Tests.csproj
index 5bb3d121fba..ccd6f8f26f9 100644
--- a/ILSpy.Tests/ILSpy.Tests.csproj
+++ b/ILSpy.Tests/ILSpy.Tests.csproj
@@ -34,6 +34,7 @@
   </PropertyGroup>
 
   <ItemGroup>
+    <Compile Include="Analyzers\AnalyserScopeTests.cs" />
     <Compile Include="Analyzers\MemberImplementsInterfaceAnalyzerTests.cs" />
     <Compile Include="Analyzers\MethodUsesAnalyzerTests.cs" />
     <Compile Include="Analyzers\TestCases\MainAssembly.cs" />
diff --git a/ILSpy/Analyzers/AnalyzerScope.cs b/ILSpy/Analyzers/AnalyzerScope.cs
index 4560ce535ed..fe844a33b96 100644
--- a/ILSpy/Analyzers/AnalyzerScope.cs
+++ b/ILSpy/Analyzers/AnalyzerScope.cs
@@ -122,7 +122,7 @@ static void DetermineEffectiveAccessibility(IEntity input, out ITypeDefinition t
 			while (typeScope != null && !accessibility.LessThanOrEqual(Accessibility.Private))
 			{
 				accessibility = accessibility.Intersect(typeScope.Accessibility);
-				typeScope = prevTypeScope.DeclaringTypeDefinition;
+				typeScope = typeScope.DeclaringTypeDefinition;
 			}
 			if (typeScope == null)
 			{