Adjust CapturedVariables collection in ReplaceDelegateTargetVisitor and in TransformExpressionTrees

ICSharpCode.Decompiler/IL/Instructions/ILFunction.cs

@@ -77,7 +77,7 @@ namespace ICSharpCode.Decompiler.IL
 		/// Gets the set of captured variables by this ILFunction.
 		/// </summary>
 		/// <remarks>This is populated by the <see cref="TransformDisplayClassUsage" /> step.</remarks>
-		public HashSet<ILVariable> CapturedVariables { get; } = new HashSet<ILVariable>(ILVariableEqualityComparer.Instance);
+		public HashSet<ILVariable> CapturedVariables { get; } = new HashSet<ILVariable>();
 
 		/// <summary>
 		/// List of warnings of ILReader.

ICSharpCode.Decompiler/IL/Transforms/DelegateConstruction.cs

@@ -238,7 +238,30 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 					child.AcceptVisitor(this);
 				}
 			}
-			
+
+			protected internal override void VisitILFunction(ILFunction function)
+			{
+				if (function == thisVariable?.Function) {
+					ILVariable v = null;
+					switch (target) {
+						case LdLoc l:
+							v = l.Variable;
+							break;
+						case LdObj lo:
+							ILInstruction inner = lo.Target;
+							while (inner is LdFlda ldf) {
+								inner = ldf.Target;
+							}
+							if (inner is LdLoc l2)
+								v = l2.Variable;
+							break;
+					}
+					if (v != null)
+						function.CapturedVariables.Add(v);
+				}
+				base.VisitILFunction(function);
+			}
+
 			protected internal override void VisitLdLoc(LdLoc inst)
 			{
 				if (inst.Variable == thisVariable) {

ICSharpCode.Decompiler/IL/Transforms/TransformExpressionTrees.cs

@@ -1229,6 +1229,10 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 						}
 						if (ldloc.Variable.CaptureScope == null) {
 							ldloc.Variable.CaptureScope = BlockContainer.FindClosestContainer(context);
+							var f = ldloc.Variable.CaptureScope.Ancestors.OfType<ILFunction>().FirstOrDefault();
+							if (f != null) {
+								f.CapturedVariables.Add(ldloc.Variable);
+							}
 						}
 						return ldloc;
 					} else {