Move debug-step stepping to a neutral namespace

The step recorder is shared by C# AST and ILAst replay, so keep the public infrastructure out of IL.Transforms and pass language-specific node navigation through neutral node metadata.

Assisted-by: OpenCode:openai/gpt-5.5:OpenCode

ICSharpCode.Decompiler/CSharp/CSharpDecompiler.cs

@@ -33,6 +33,7 @@ using ICSharpCode.Decompiler.CSharp.Resolver;
 using ICSharpCode.Decompiler.CSharp.Syntax;
 using ICSharpCode.Decompiler.CSharp.Transforms;
 using ICSharpCode.Decompiler.CSharp.TypeSystem;
+using ICSharpCode.Decompiler.DebugSteps;
 using ICSharpCode.Decompiler.DebugInfo;
 using ICSharpCode.Decompiler.Disassembler;
 using ICSharpCode.Decompiler.Documentation;

ICSharpCode.Decompiler/CSharp/Transforms/TransformContext.cs

@@ -24,7 +24,7 @@ using System.Diagnostics;
 using System.Threading;
 
 using ICSharpCode.Decompiler.CSharp.Syntax;
-using ICSharpCode.Decompiler.IL.Transforms;
+using ICSharpCode.Decompiler.DebugSteps;
 using ICSharpCode.Decompiler.TypeSystem;
 
 namespace ICSharpCode.Decompiler.CSharp.Transforms
@@ -82,29 +82,14 @@ namespace ICSharpCode.Decompiler.CSharp.Transforms
 		[DebuggerStepThrough]
 		internal void Step(string description, AstNode? near = null)
 		{
-			Stepper.Node stepNode;
+			Stepper.Step(description, CreateNodeInfo(near));
-			try
-			{
-				stepNode = Stepper.Step(description, modifiedNode: near);
-			}
-			catch (StepLimitReachedException)
-			{
-				// The limit fell on this step: Stepper recorded it as LimitReachedStep but threw
-				// before we could attach the node candidates. Attach them to the limit-reached node
-				// (the tree is still in its pre-mutation state) so the "show state before" view can
-				// locate the change, mirroring how the IL path records candidates before its throw.
-				if (Stepper.LimitReachedStep is { } limitStep)
-					TrackModifiedNode(limitStep, near);
-				throw;
-			}
-			TrackModifiedNode(stepNode, near);
 		}
 
 		[Conditional("STEP")]
 		[DebuggerStepThrough]
 		internal void StepStartGroup(string description, AstNode? near = null)
 		{
-			TrackModifiedNode(Stepper.StartGroup(description, modifiedNode: near), near);
+			Stepper.StartGroup(description, CreateNodeInfo(near));
 		}
 
 		[Conditional("STEP")]
@@ -123,28 +108,28 @@ namespace ICSharpCode.Decompiler.CSharp.Transforms
 		{
 			if (Stepper.LastStep != null && modifiedNode != null)
 			{
+				var marker = new DebugStepMarker();
+				modifiedNode.AddAnnotation(marker);
 				Stepper.LastStep.ModifiedNode = modifiedNode;
-				TrackModifiedNode(Stepper.LastStep, modifiedNode, insertFirst: true);
+				Stepper.LastStep.RecordModifiedNode(modifiedNode, extraIdentity: marker, insertFirst: true);
 			}
 		}
 
-		static void TrackModifiedNode(Stepper.Node step, AstNode? modifiedNode, bool insertFirst = false)
+		static DebugStepNodeInfo? CreateNodeInfo(AstNode? modifiedNode)
 		{
 			if (modifiedNode == null)
-				return;
+				return null;
 			// The marker rides CopyAnnotationsFrom so a replaced node's step still resolves to the
 			// emitted text; it is recorded as a second identity for the changed node. The seam
-			// neighbours and ancestor chain are captured from the original node on the initial pass
+			// neighbors and ancestor chain are captured from the original node before mutation.
-			// (insertFirst == false); a produced-node update only prepends the new node.
 			var marker = new DebugStepMarker();
 			modifiedNode.AddAnnotation(marker);
-			step.RecordModifiedNode(
+			return new DebugStepNodeInfo(
 				modifiedNode,
-				insertFirst ? null : modifiedNode.NextSibling,
+				modifiedNode.NextSibling,
-				insertFirst ? null : modifiedNode.PrevSibling,
+				modifiedNode.PrevSibling,
-				insertFirst ? null : Ancestors(modifiedNode),
+				Ancestors(modifiedNode),
-				extraIdentity: marker,
+				extraIdentity: marker);
-				insertFirst: insertFirst);
 
 			static IEnumerable<object> Ancestors(AstNode node)
 			{
@@ -154,13 +139,4 @@ namespace ICSharpCode.Decompiler.CSharp.Transforms
 		}
 	}
 
-	/// <summary>
-	/// Annotation attached to a step's modified node so the debug-step highlighter can still locate
-	/// that node's rendered range after a later transform copies its annotations onto a replacement
-	/// (via CopyAnnotationsFrom). This is the only annotation <c>NodeLookup</c> bridges to a text
-	/// range; indexing every annotation would add dead keys and let shared ones collide by identity.
-	/// </summary>
-	public sealed class DebugStepMarker
-	{
-	}
 }

ICSharpCode.Decompiler/DebugSteps/Stepper.cs

@@ -25,15 +25,41 @@ using System.Linq;
 
 using ICSharpCode.Decompiler.Util;
 
-namespace ICSharpCode.Decompiler.IL.Transforms
+namespace ICSharpCode.Decompiler.DebugSteps
 {
 	/// <summary>
-	/// Exception thrown when an IL transform runs into the <see cref="Stepper.StepLimit"/>.
+	/// Exception thrown when a debug-step-enabled transform pipeline runs into the <see cref="Stepper.StepLimit"/>.
 	/// </summary>
 	public class StepLimitReachedException : Exception
 	{
 	}
 
+	/// <summary>
+	/// Language-specific node identities and navigation data captured before a transform mutation.
+	/// </summary>
+	public readonly struct DebugStepNodeInfo
+	{
+		public object Node { get; }
+		public object? NextSibling { get; }
+		public object? PreviousSibling { get; }
+		public IEnumerable<object>? Ancestors { get; }
+		public object? ExtraIdentity { get; }
+
+		public DebugStepNodeInfo(
+			object node,
+			object? nextSibling = null,
+			object? previousSibling = null,
+			IEnumerable<object>? ancestors = null,
+			object? extraIdentity = null)
+		{
+			Node = node ?? throw new ArgumentNullException(nameof(node));
+			NextSibling = nextSibling;
+			PreviousSibling = previousSibling;
+			Ancestors = ancestors;
+			ExtraIdentity = extraIdentity;
+		}
+	}
+
 	/// <summary>
 	/// Helper class that manages recording transform steps.
 	/// </summary>
@@ -63,7 +89,7 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 		public class Node
 		{
 			public string Description { get; }
-			public ILInstruction? Position { get; set; }
+			public object? Position { get; set; }
 			public object? ModifiedNode { get; set; }
 			/// <summary>
 			/// Precise identities of the changed node (the node itself, its debug-step marker, and
@@ -71,14 +97,14 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 			/// </summary>
 			public IList<object> ModifiedNodeCandidates { get; } = new List<object>();
 			/// <summary>
-			/// Neighbours of the changed node, recorded before the mutation. When the node itself is
+			/// Neighbors of the changed node, recorded before the mutation. When the node itself is
 			/// gone from the rendered text (a removal), a caret is placed at the gap they leave:
-			/// at the start of a following neighbour, or the end of a preceding one (AtEnd).
+			/// at the start of a following neighbor, or the end of a preceding one (AtEnd).
 			/// </summary>
 			public IList<(object Anchor, bool AtEnd)> SeamAnchors { get; } = new List<(object, bool)>();
 			/// <summary>
 			/// The changed node's ancestor chain, resolved as a last resort when neither the node
-			/// nor a seam neighbour has a rendered range.
+			/// nor a seam neighbor has a rendered range.
 			/// </summary>
 			public IList<object> AncestorCandidates { get; } = new List<object>();
 			/// <summary>
@@ -101,12 +127,23 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 			/// Records the highlight candidates for this step from an already-navigated node: the
 			/// node's identity (optionally a second identity such as a debug-step marker), its
 			/// immediate siblings as seam anchors, and its ancestor chain. Callers pass the
-			/// neighbours because <see cref="ILInstruction"/> and the C# AST expose navigation
+			/// neighbors because each transform representation exposes navigation differently;
-			/// differently; the ordering/dedup/seam strategy lives here so the two languages'
+			/// the ordering/dedup/seam strategy lives here so languages'
 			/// recording can't drift. <paramref name="insertFirst"/> marks a produced-node update
 			/// (from EndStep): the node is preferred over existing candidates and the seam and
 			/// ancestor anchors are left untouched, since they were captured from the original node.
 			/// </summary>
+			public void RecordModifiedNode(DebugStepNodeInfo modifiedNode, bool insertFirst = false)
+			{
+				RecordModifiedNode(
+					modifiedNode.Node,
+					modifiedNode.NextSibling,
+					modifiedNode.PreviousSibling,
+					modifiedNode.Ancestors,
+					modifiedNode.ExtraIdentity,
+					insertFirst);
+			}
+
 			public void RecordModifiedNode(
 				object node,
 				object? nextSibling = null,
@@ -159,44 +196,21 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 		/// May throw <see cref="StepLimitReachedException"/> in debug mode.
 		/// </summary>
 		[DebuggerStepThrough]
-		public Node Step(string description, ILInstruction? near = null, object? modifiedNode = null)
+		public Node Step(string description, DebugStepNodeInfo? modifiedNode = null)
-		{
-			return StepInternal(description, near, modifiedNode ?? near);
-		}
-
-		[DebuggerStepThrough]
-		private Node StepInternal(string description, ILInstruction? near, object? modifiedNode)
 		{
+			object? node = modifiedNode?.Node;
 			var stepNode = new Node($"{step}: {description}") {
-				Position = near,
+				Position = node,
-				ModifiedNode = modifiedNode,
+				ModifiedNode = node,
 				BeginStep = step,
 				EndStep = step + 1
 			};
-			// Record the IL position, its neighbours, and its ancestor chain as highlight candidates
+			// Record highlight candidates before the limit-reached check below can throw: the debug-step
-			// here, before the limit-reached check below can throw: the debug-step view halts the
+			// view halts the pipeline at the selected step, so that step would otherwise carry no
-			// pipeline at the selected step, so that step would otherwise carry no candidates and the
+			// candidates and the "show state before" view could not locate the change.
-			// "show state before" view could not locate the change. A later transform may detach the
+			if (modifiedNode is { } info)
-			// exact instruction; a surviving neighbour then anchors a seam caret, and failing that a
-			// surviving ancestor (ultimately the ILFunction) still resolves.
-			if (near != null)
-			{
-				object? next = null, prev = null;
-				if (near.Parent is { } parent)
-				{
-					int index = near.ChildIndex;
-					if (index + 1 < parent.Children.Count)
-						next = parent.Children[index + 1];
-					if (index - 1 >= 0)
-						prev = parent.Children[index - 1];
-				}
-				stepNode.RecordModifiedNode(near, next, prev, Ancestors(near));
-
-				static IEnumerable<object> Ancestors(ILInstruction inst)
 			{
-					for (var node = inst.Parent; node != null; node = node.Parent)
+				stepNode.RecordModifiedNode(info);
-						yield return node;
-				}
 			}
 			if (step == StepLimit)
 			{
@@ -217,9 +231,9 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 		}
 
 		[DebuggerStepThrough]
-		public Node StartGroup(string description, ILInstruction? near = null, object? modifiedNode = null)
+		public Node StartGroup(string description, DebugStepNodeInfo? modifiedNode = null)
 		{
-			var stepNode = StepInternal(description, near, modifiedNode ?? near);
+			var stepNode = Step(description, modifiedNode);
 			groups.Push(stepNode);
 			return stepNode;
 		}
@@ -254,4 +268,14 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 			node.EndStep = step;
 		}
 	}
+
+	/// <summary>
+	/// Annotation attached to a step's modified node so the debug-step highlighter can still locate
+	/// that node's rendered range after a later transform copies its annotations onto a replacement
+	/// (via CopyAnnotationsFrom). This is the only annotation the UI bridges to a text range; indexing
+	/// every annotation would add dead keys and let shared ones collide by identity.
+	/// </summary>
+	public sealed class DebugStepMarker
+	{
+	}
 }

ICSharpCode.Decompiler/IL/Transforms/IILTransform.cs

@@ -19,11 +19,13 @@
 #nullable enable
 
 using System;
+using System.Collections.Generic;
 using System.Diagnostics;
 using System.Threading;
 
 using ICSharpCode.Decompiler.CSharp.Resolver;
 using ICSharpCode.Decompiler.CSharp.TypeSystem;
+using ICSharpCode.Decompiler.DebugSteps;
 using ICSharpCode.Decompiler.DebugInfo;
 using ICSharpCode.Decompiler.TypeSystem;
 using ICSharpCode.Decompiler.Util;
@@ -105,14 +107,14 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 		[DebuggerStepThrough]
 		internal void Step(string description, ILInstruction? near)
 		{
-			Stepper.Step(description, near);
+			Stepper.Step(description, CreateNodeInfo(near));
 		}
 
 		[Conditional("STEP")]
 		[DebuggerStepThrough]
 		internal void StepStartGroup(string description, ILInstruction? near = null)
 		{
-			Stepper.StartGroup(description, near);
+			Stepper.StartGroup(description, CreateNodeInfo(near));
 		}
 
 		[Conditional("STEP")]
@@ -138,5 +140,27 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 				step.RecordModifiedNode(modifiedNode, insertFirst: true);
 			}
 		}
+
+		static DebugStepNodeInfo? CreateNodeInfo(ILInstruction? instruction)
+		{
+			if (instruction == null)
+				return null;
+			object? next = null, previous = null;
+			if (instruction.Parent is { } parent)
+			{
+				int index = instruction.ChildIndex;
+				if (index + 1 < parent.Children.Count)
+					next = parent.Children[index + 1];
+				if (index - 1 >= 0)
+					previous = parent.Children[index - 1];
+			}
+			return new DebugStepNodeInfo(instruction, next, previous, Ancestors(instruction));
+
+			static IEnumerable<object> Ancestors(ILInstruction instruction)
+			{
+				for (var node = instruction.Parent; node != null; node = node.Parent)
+					yield return node;
+			}
+		}
 	}
 }

ILSpy.Tests/Views/DebugStepsTests.cs

@@ -33,6 +33,7 @@ using AwesomeAssertions;
 using ICSharpCode.Decompiler.CSharp;
 using ICSharpCode.Decompiler.CSharp.Syntax;
 using ICSharpCode.Decompiler.CSharp.Transforms;
+using ICSharpCode.Decompiler.DebugSteps;
 
 using ICSharpCode.ILSpy;
 using ICSharpCode.ILSpy.AppEnv;
@@ -239,8 +240,7 @@ public class DebugStepsTests
 
 		// The first leaf step that acts on a concrete instruction; a step whose Position is null
 		// (e.g. an empty transform group) has nothing to highlight and is not what a user replays.
-		static ICSharpCode.Decompiler.IL.Transforms.Stepper.Node? FirstLeafStep(
+		static Stepper.Node? FirstLeafStep(System.Collections.Generic.IEnumerable<Stepper.Node> steps)
-			System.Collections.Generic.IEnumerable<ICSharpCode.Decompiler.IL.Transforms.Stepper.Node> steps)
 		{
 			foreach (var step in steps)
 			{
@@ -304,37 +304,37 @@ public class DebugStepsTests
 	public Task DebugStepHighlighter_Removal_Resolves_To_Seam_Caret()
 	{
 		// A step whose node was removed has no precise range and (in this fixture) no rendered
-		// ancestor, only surviving neighbours. It must resolve to a zero-length caret at the gap:
+		// ancestor, only surviving neighbors. It must resolve to a zero-length caret at the gap:
 		// the successor's start when one survives, otherwise the predecessor's end.
 		var successor = new object();
 		var predecessor = new object();
 
 		var successorLookup = new NodeLookup();
 		successorLookup.AddNode(successor, 40, 6);
-		var removalWithSuccessor = new ICSharpCode.Decompiler.IL.Transforms.Stepper.Node("0: Remove statement") {
+		var removalWithSuccessor = new Stepper.Node("0: Remove statement") {
 			BeginStep = 0,
 			EndStep = 1
 		};
 		removalWithSuccessor.SeamAnchors.Add((successor, false));
 		removalWithSuccessor.SeamAnchors.Add((predecessor, true));
-		var successorStepper = new ICSharpCode.Decompiler.IL.Transforms.Stepper();
+		var successorStepper = new Stepper();
 		successorStepper.Steps.Add(removalWithSuccessor);
 
 		DebugStepHighlighter.TryResolve(successorStepper, stepLimit: 1, highlightStep: 0, successorLookup, out var caret)
-			.Should().BeTrue("a removed node must still resolve to a surviving seam neighbour");
+			.Should().BeTrue("a removed node must still resolve to a surviving seam neighbor");
 		caret.Length.Should().Be(0, "a removal has no text to highlight, only a caret at the gap");
 		caret.Start.Should().Be(40, "the caret sits at the successor's start, where the node was");
 
 		// Only the predecessor survives: the caret sits at its end (10 + 5).
 		var predecessorLookup = new NodeLookup();
 		predecessorLookup.AddNode(predecessor, 10, 5);
-		var removalWithPredecessor = new ICSharpCode.Decompiler.IL.Transforms.Stepper.Node("0: Remove statement") {
+		var removalWithPredecessor = new Stepper.Node("0: Remove statement") {
 			BeginStep = 0,
 			EndStep = 1
 		};
 		removalWithPredecessor.SeamAnchors.Add((successor, false));
 		removalWithPredecessor.SeamAnchors.Add((predecessor, true));
-		var predecessorStepper = new ICSharpCode.Decompiler.IL.Transforms.Stepper();
+		var predecessorStepper = new Stepper();
 		predecessorStepper.Steps.Add(removalWithPredecessor);
 
 		DebugStepHighlighter.TryResolve(predecessorStepper, stepLimit: 1, highlightStep: 0, predecessorLookup, out var endCaret)
@@ -348,9 +348,9 @@ public class DebugStepsTests
 	public Task DebugStepFilter_Keeps_Matches_And_The_Path_To_Them()
 	{
 		var converter = new DebugStepFilterConverter();
-		var matchingLeaf = new ICSharpCode.Decompiler.IL.Transforms.Stepper.Node("3: Introduce query continuation");
+		var matchingLeaf = new Stepper.Node("3: Introduce query continuation");
-		var otherLeaf = new ICSharpCode.Decompiler.IL.Transforms.Stepper.Node("4: Flatten switch section block");
+		var otherLeaf = new Stepper.Node("4: Flatten switch section block");
-		var group = new ICSharpCode.Decompiler.IL.Transforms.Stepper.Node("CombineQueryExpressions");
+		var group = new Stepper.Node("CombineQueryExpressions");
 		group.Children.Add(matchingLeaf);
 		group.Children.Add(otherLeaf);
 
@@ -365,7 +365,7 @@ public class DebugStepsTests
 		Filter(otherLeaf, "continuation").Should().BeFalse();
 		return Task.CompletedTask;
 
-		bool Filter(ICSharpCode.Decompiler.IL.Transforms.Stepper.Node node, string filter)
+		bool Filter(Stepper.Node node, string filter)
 			=> (bool)converter.Convert(new object?[] { node, filter }, typeof(bool), null, CultureInfo.InvariantCulture);
 	}
 
@@ -377,9 +377,9 @@ public class DebugStepsTests
 		// would not catch at build time. Realising the view with a populated tree and a live filter
 		// must not throw.
 		var vm = new DebugStepsPaneModel();
-		var group = new ICSharpCode.Decompiler.IL.Transforms.Stepper.Node("CombineQueryExpressions");
+		var group = new Stepper.Node("CombineQueryExpressions");
-		group.Children.Add(new ICSharpCode.Decompiler.IL.Transforms.Stepper.Node("3: Introduce query continuation"));
+		group.Children.Add(new Stepper.Node("3: Introduce query continuation"));
-		group.Children.Add(new ICSharpCode.Decompiler.IL.Transforms.Stepper.Node("4: Flatten switch section block"));
+		group.Children.Add(new Stepper.Node("4: Flatten switch section block"));
 		vm.Steps = new[] { group };
 		vm.IsAvailable = true;
 
@@ -483,7 +483,7 @@ public class DebugStepsTests
 		debugStepsVm.IsAvailable.Should().BeTrue("C# provides debug steps");
 
 		// Simulate a populated tree from the C# run, then flip to the disassembler language.
-		debugStepsVm.Steps = new[] { new ICSharpCode.Decompiler.IL.Transforms.Stepper.Node("stale") };
+		debugStepsVm.Steps = new[] { new Stepper.Node("stale") };
 		languageService.CurrentLanguage = languageService.Languages.OfType<ILLanguage>().First(l => l.Name == "IL");
 		global::Avalonia.Threading.Dispatcher.UIThread.RunJobs();
 

ILSpy/Languages/CSharpLanguage.DebugSteps.cs

@@ -22,7 +22,7 @@ using System;
 
 using ICSharpCode.Decompiler;
 using ICSharpCode.Decompiler.CSharp;
-using ICSharpCode.Decompiler.IL.Transforms;
+using ICSharpCode.Decompiler.DebugSteps;
 
 using ICSharpCode.ILSpy.AppEnv;
 using ICSharpCode.ILSpy.Docking;

ILSpy/Languages/CSharpLanguage.cs

@@ -32,8 +32,8 @@ using ICSharpCode.Decompiler.CSharp.OutputVisitor;
 using ICSharpCode.Decompiler.CSharp.ProjectDecompiler;
 using ICSharpCode.Decompiler.CSharp.Syntax;
 using ICSharpCode.Decompiler.CSharp.Transforms;
+using ICSharpCode.Decompiler.DebugSteps;
 using ICSharpCode.Decompiler.IL;
-using ICSharpCode.Decompiler.IL.Transforms;
 using ICSharpCode.Decompiler.Metadata;
 using ICSharpCode.Decompiler.Output;
 using ICSharpCode.Decompiler.Solution;

ILSpy/Languages/IDebugStepProvider.cs

@@ -20,7 +20,7 @@
 
 using System;
 
-using ICSharpCode.Decompiler.IL.Transforms;
+using ICSharpCode.Decompiler.DebugSteps;
 
 namespace ICSharpCode.ILSpy.Languages
 {

ILSpy/Languages/ILAstLanguage.cs

@@ -24,6 +24,7 @@ using System.Composition;
 
 using ICSharpCode.Decompiler;
 using ICSharpCode.Decompiler.CSharp;
+using ICSharpCode.Decompiler.DebugSteps;
 using ICSharpCode.Decompiler.Disassembler;
 using ICSharpCode.Decompiler.IL;
 using ICSharpCode.Decompiler.IL.Transforms;

ILSpy/TextView/DebugStepHighlighter.cs

@@ -16,7 +16,7 @@
 // OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 // DEALINGS IN THE SOFTWARE.
 
-using ICSharpCode.Decompiler.IL.Transforms;
+using ICSharpCode.Decompiler.DebugSteps;
 
 namespace ICSharpCode.ILSpy.TextView
 {
@@ -71,7 +71,7 @@ namespace ICSharpCode.ILSpy.TextView
 			if (step.ModifiedNode != null && nodeLookup.TryGetRange(step.ModifiedNode, out range))
 				return true;
 			// The node itself is gone (a removal): point a zero-length caret at the gap it left,
-			// anchored to a surviving neighbour, rather than flooding the enclosing block.
+			// anchored to a surviving neighbor, rather than flooding the enclosing block.
 			foreach (var (anchor, atEnd) in step.SeamAnchors)
 			{
 				if (nodeLookup.TryGetRange(anchor, out var anchorRange))

ILSpy/TextView/NodeLookup.cs

@@ -19,7 +19,7 @@
 using System.Collections.Generic;
 
 using ICSharpCode.Decompiler.CSharp.Syntax;
-using ICSharpCode.Decompiler.CSharp.Transforms;
+using ICSharpCode.Decompiler.DebugSteps;
 
 namespace ICSharpCode.ILSpy.TextView
 {

ILSpy/ViewModels/DebugStepsPaneModel.cs

@@ -27,8 +27,8 @@ using Avalonia.Threading;
 using CommunityToolkit.Mvvm.ComponentModel;
 using CommunityToolkit.Mvvm.Input;
 
+using ICSharpCode.Decompiler.DebugSteps;
 using ICSharpCode.Decompiler.IL;
-using ICSharpCode.Decompiler.IL.Transforms;
 
 using ICSharpCode.ILSpy.AppEnv;
 using ICSharpCode.ILSpy.Commands;

ILSpy/Views/DebugStepFilterConverter.cs

@@ -24,7 +24,7 @@ using System.Globalization;
 
 using Avalonia.Data.Converters;
 
-using ICSharpCode.Decompiler.IL.Transforms;
+using ICSharpCode.Decompiler.DebugSteps;
 
 namespace ICSharpCode.ILSpy.Views
 {