Generate DoMatch for the expression nodes

Replace the hand-written DoMatch overrides on the expression nodes with
generated ones. The generator matches every real child and structural member,
so several matchers become stricter than the hand-written versions that
under-matched (for example a previously-skipped child or an ignored flag),
while Pretty output is unaffected. Convenience-string identifier slots are
excluded so the name string is matched once rather than also via its token.
Assisted-by: Claude:claude-opus-4-8:Claude Code

ICSharpCode.Decompiler.Generators/DecompilerSyntaxTreeGenerator.cs

@@ -270,6 +270,7 @@ internal class DecompilerSyntaxTreeGenerator : IIncrementalGenerator
 	{{
 		return visitor.Visit{source.VisitMethodName}(this, data);
 	}}
+
 ");
 		}
 
@@ -310,6 +311,7 @@ internal class DecompilerSyntaxTreeGenerator : IIncrementalGenerator
 
 			builder.Append(@";
 	}
+
 ");
 		}
 
@@ -338,6 +340,7 @@ internal class DecompilerSyntaxTreeGenerator : IIncrementalGenerator
 					builder.AppendLine($"\t\tset => SetChildNode(ref {field}, value, {roleExpr});");
 					builder.AppendLine("\t}");
 				}
+				builder.AppendLine();
 			}
 
 			// Flattened child-index space: slots in declaration order, a single slot occupying one index
@@ -345,6 +348,7 @@ internal class DecompilerSyntaxTreeGenerator : IIncrementalGenerator
 			builder.Append("\tinternal override int GetChildCount() => ");
 			builder.Append(string.Join(" + ", slots.Select(s => s.IsCollection ? $"({FieldName(s.PropertyName)}?.Count ?? 0)" : "1")));
 			builder.AppendLine(";");
+			builder.AppendLine();
 
 			builder.AppendLine("\tinternal override AstNode? GetChild(int index)");
 			builder.AppendLine("\t{");
@@ -363,6 +367,7 @@ internal class DecompilerSyntaxTreeGenerator : IIncrementalGenerator
 			}
 			builder.AppendLine("\t\tthrow new System.ArgumentOutOfRangeException(nameof(index));");
 			builder.AppendLine("\t}");
+			builder.AppendLine();
 
 			builder.AppendLine("\tinternal override void SetChild(int index, AstNode? value)");
 			builder.AppendLine("\t{");
@@ -381,6 +386,7 @@ internal class DecompilerSyntaxTreeGenerator : IIncrementalGenerator
 			}
 			builder.AppendLine("\t\tthrow new System.ArgumentOutOfRangeException(nameof(index));");
 			builder.AppendLine("\t}");
+			builder.AppendLine();
 
 			builder.AppendLine("\tinternal override Role GetChildSlot(int index)");
 			builder.AppendLine("\t{");
@@ -394,10 +400,12 @@ internal class DecompilerSyntaxTreeGenerator : IIncrementalGenerator
 			}
 			builder.AppendLine("\t\tthrow new System.ArgumentOutOfRangeException(nameof(index));");
 			builder.AppendLine("\t}");
+			builder.AppendLine();
 
 			// One CSharpSlotInfo static per slot; node.Slot compares against these by object identity.
 			foreach (var s in slots)
 				builder.AppendLine($"\tpublic static readonly CSharpSlotInfo {s.PropertyName}Slot = new CSharpSlotInfo(\"{s.PropertyName}\", typeof({s.ElementType}), {(s.IsCollection ? "true" : "false")}, SlotKind.{s.KindName});");
+			builder.AppendLine();
 
 			builder.AppendLine("\tinternal override CSharpSlotInfo GetChildSlotInfo(int index)");
 			builder.AppendLine("\t{");
@@ -411,6 +419,7 @@ internal class DecompilerSyntaxTreeGenerator : IIncrementalGenerator
 			}
 			builder.AppendLine("\t\tthrow new System.ArgumentOutOfRangeException(nameof(index));");
 			builder.AppendLine("\t}");
+			builder.AppendLine();
 
 			if (slots.Any(s => s.IsCollection))
 			{
@@ -420,6 +429,7 @@ internal class DecompilerSyntaxTreeGenerator : IIncrementalGenerator
 					builder.AppendLine($"\t\tif (role == {s.RoleExpr}) return {s.PropertyName};");
 				builder.AppendLine("\t\treturn base.GetCollectionByRole(role);");
 				builder.AppendLine("\t}");
+				builder.AppendLine();
 			}
 
 			builder.AppendLine("\tinternal override void CloneChildrenInto(AstNode copyNode)");
@@ -436,11 +446,12 @@ internal class DecompilerSyntaxTreeGenerator : IIncrementalGenerator
 					builder.AppendLine($"\t\tif ({field} != null) copy.{s.PropertyName} = ({s.PropertyType}){field}.Clone();");
 			}
 			builder.AppendLine("\t}");
+			builder.AppendLine();
 		}
 
 		builder.AppendLine("}");
 
-		context.AddSource(source.NodeName + ".g.cs", SourceText.From(builder.ToString(), Encoding.UTF8));
+		context.AddSource(source.NodeName + ".g.cs", SourceText.From(builder.ToString().Replace("\r\n", "\n"), Encoding.UTF8));
 	}
 
 	void WriteVisitors(SourceProductionContext context, ImmutableArray<AstNodeAdditions> source)

ICSharpCode.Decompiler/CSharp/Syntax/Expressions/IdentifierExpression.cs

@@ -55,6 +55,8 @@ namespace ICSharpCode.Decompiler.CSharp.Syntax
 			}
 		}
 
+		// The Identifier string is what DoMatch compares; the token slot is excluded to avoid matching it twice.
+		[ExcludeFromMatch]
 		[Slot("Roles.Identifier")]
 		public partial Identifier IdentifierToken { get; set; }
 

ICSharpCode.Decompiler/CSharp/Syntax/Expressions/IndexerExpression.cs

@@ -59,11 +59,5 @@ namespace ICSharpCode.Decompiler.CSharp.Syntax
 		public IndexerExpression(Expression target, params Expression[] arguments) : this(target, (IEnumerable<Expression>)arguments)
 		{
 		}
-
-		protected internal override bool DoMatch(AstNode other, PatternMatching.Match match)
-		{
-			IndexerExpression o = other as IndexerExpression;
-			return o != null && this.Target.DoMatch(o.Target, match) && this.Arguments.DoMatch(o.Arguments, match);
-		}
 	}
 }

ICSharpCode.Decompiler/CSharp/Syntax/Expressions/InterpolatedStringExpression.cs

@@ -1,7 +1,5 @@
 using System.Collections.Generic;
 
-using ICSharpCode.Decompiler.CSharp.Syntax.PatternMatching;
-
 namespace ICSharpCode.Decompiler.CSharp.Syntax
 {
 	/// <summary>
@@ -25,12 +23,6 @@ namespace ICSharpCode.Decompiler.CSharp.Syntax
 		{
 			Content.AddRange(content);
 		}
-
-		protected internal override bool DoMatch(AstNode other, Match match)
-		{
-			InterpolatedStringExpression o = other as InterpolatedStringExpression;
-			return o != null && !o.IsNull && this.Content.DoMatch(o.Content, match);
-		}
 	}
 
 	[DecompilerAstNode(hasNullNode: true)]
@@ -68,12 +60,6 @@ namespace ICSharpCode.Decompiler.CSharp.Syntax
 			Alignment = alignment;
 			Suffix = suffix;
 		}
-
-		protected internal override bool DoMatch(AstNode other, Match match)
-		{
-			Interpolation o = other as Interpolation;
-			return o != null && this.Expression.DoMatch(o.Expression, match);
-		}
 	}
 
 	/// <summary>
@@ -93,11 +79,5 @@ namespace ICSharpCode.Decompiler.CSharp.Syntax
 		{
 			Text = text;
 		}
-
-		protected internal override bool DoMatch(AstNode other, Match match)
-		{
-			InterpolatedStringText o = other as InterpolatedStringText;
-			return o != null && o.Text == this.Text;
-		}
 	}
 }

ICSharpCode.Decompiler/CSharp/Syntax/Expressions/InvocationExpression.cs

@@ -59,11 +59,5 @@ namespace ICSharpCode.Decompiler.CSharp.Syntax
 		public InvocationExpression(Expression target, params Expression[] arguments) : this(target, (IEnumerable<Expression>)arguments)
 		{
 		}
-
-		protected internal override bool DoMatch(AstNode other, PatternMatching.Match match)
-		{
-			InvocationExpression o = other as InvocationExpression;
-			return o != null && this.Target.DoMatch(o.Target, match) && this.Arguments.DoMatch(o.Arguments, match);
-		}
 	}
 }

ICSharpCode.Decompiler/CSharp/Syntax/Expressions/IsExpression.cs

@@ -50,12 +50,6 @@ namespace ICSharpCode.Decompiler.CSharp.Syntax
 			AddChild(expression, Roles.Expression);
 			AddChild(type, Roles.Type);
 		}
-
-		protected internal override bool DoMatch(AstNode other, PatternMatching.Match match)
-		{
-			IsExpression o = other as IsExpression;
-			return o != null && this.Expression.DoMatch(o.Expression, match) && this.Type.DoMatch(o.Type, match);
-		}
 	}
 }
 

ICSharpCode.Decompiler/CSharp/Syntax/Expressions/LambdaExpression.cs

@@ -51,11 +51,5 @@ namespace ICSharpCode.Decompiler.CSharp.Syntax
 
 		[Slot("BodyRole")]
 		public partial AstNode Body { get; set; }
-
-		protected internal override bool DoMatch(AstNode other, PatternMatching.Match match)
-		{
-			LambdaExpression o = other as LambdaExpression;
-			return o != null && this.IsAsync == o.IsAsync && this.Parameters.DoMatch(o.Parameters, match) && this.Body.DoMatch(o.Body, match);
-		}
 	}
 }

ICSharpCode.Decompiler/CSharp/Syntax/Expressions/MemberReferenceExpression.cs

@@ -46,6 +46,8 @@ namespace ICSharpCode.Decompiler.CSharp.Syntax
 			}
 		}
 
+		// DoMatch compares the MemberName string; exclude the token slot to avoid matching it twice.
+		[ExcludeFromMatch]
 		[Slot("Roles.Identifier")]
 		public partial Identifier MemberNameToken { get; set; }
 
@@ -72,11 +74,5 @@ namespace ICSharpCode.Decompiler.CSharp.Syntax
 		public MemberReferenceExpression(Expression target, string memberName, params AstType[] arguments) : this(target, memberName, (IEnumerable<AstType>)arguments)
 		{
 		}
-
-		protected internal override bool DoMatch(AstNode other, PatternMatching.Match match)
-		{
-			MemberReferenceExpression o = other as MemberReferenceExpression;
-			return o != null && this.Target.DoMatch(o.Target, match) && MatchString(this.MemberName, o.MemberName) && this.TypeArguments.DoMatch(o.TypeArguments, match);
-		}
 	}
 }

ICSharpCode.Decompiler/CSharp/Syntax/Expressions/NamedArgumentExpression.cs

@@ -44,16 +44,12 @@ namespace ICSharpCode.Decompiler.CSharp.Syntax
 			}
 		}
 
+		// DoMatch compares the Name string; exclude the token slot to avoid matching it twice.
+		[ExcludeFromMatch]
 		[Slot("Roles.Identifier")]
 		public partial Identifier NameToken { get; set; }
 
 		[Slot("Roles.Expression")]
 		public partial Expression Expression { get; set; }
-
-		protected internal override bool DoMatch(AstNode other, PatternMatching.Match match)
-		{
-			NamedArgumentExpression o = other as NamedArgumentExpression;
-			return o != null && MatchString(this.Name, o.Name) && this.Expression.DoMatch(o.Expression, match);
-		}
 	}
 }

ICSharpCode.Decompiler/CSharp/Syntax/Expressions/NamedExpression.cs

@@ -28,7 +28,7 @@ namespace ICSharpCode.Decompiler.CSharp.Syntax
 {
 	/// <summary>
 	/// No standalone expression production: 'name = value' as used in object initializers (member_initializer), anonymous-object members (member_declarator), and named attribute arguments.
-	/// <c>named_expression : identifier '=' expression ;</c>
+	/// <c>named_expression ::= identifier '=' expression</c>
 	/// </summary>
 	[DecompilerAstNode(hasNullNode: false)]
 	public partial class NamedExpression : Expression
@@ -52,16 +52,12 @@ namespace ICSharpCode.Decompiler.CSharp.Syntax
 			}
 		}
 
+		// DoMatch compares the Name string; exclude the token slot to avoid matching it twice.
+		[ExcludeFromMatch]
 		[Slot("Roles.Identifier")]
 		public partial Identifier NameToken { get; set; }
 
 		[Slot("Roles.Expression")]
 		public partial Expression Expression { get; set; }
-
-		protected internal override bool DoMatch(AstNode other, PatternMatching.Match match)
-		{
-			var o = other as NamedExpression;
-			return o != null && MatchString(this.Name, o.Name) && this.Expression.DoMatch(o.Expression, match);
-		}
 	}
 }