Refactor LocalFunctionDeclarationStatement + LocalFunctionMethod

ICSharpCode.Decompiler/CSharp/CSharpDecompiler.cs

@@ -1345,30 +1345,35 @@ namespace ICSharpCode.Decompiler.CSharp
 				}
 				entityDecl.AddAnnotation(function);
 
-				if (function.IsIterator) {
-					if (localSettings.DecompileMemberBodies && !body.Descendants.Any(d => d is YieldReturnStatement || d is YieldBreakStatement)) {
-						body.Add(new YieldBreakStatement());
-					}
-					if (function.IsAsync) {
-						RemoveAttribute(entityDecl, KnownAttribute.AsyncIteratorStateMachine);
-					} else {
-						RemoveAttribute(entityDecl, KnownAttribute.IteratorStateMachine);
-					}
-					if (function.StateMachineCompiledWithMono) {
-						RemoveAttribute(entityDecl, KnownAttribute.DebuggerHidden);
-					}
+				CleanUpMethodDeclaration(entityDecl, body, function, localSettings.DecompileMemberBodies);
+			} catch (Exception innerException) when (!(innerException is OperationCanceledException || innerException is DecompilerException)) {
+				throw new DecompilerException(module, method, innerException);
+			}
+		}
+
+		internal static void CleanUpMethodDeclaration(EntityDeclaration entityDecl, BlockStatement body, ILFunction function, bool decompileBody = true)
+		{
+			if (function.IsIterator) {
+				if (decompileBody && !body.Descendants.Any(d => d is YieldReturnStatement || d is YieldBreakStatement)) {
+					body.Add(new YieldBreakStatement());
 				}
 				if (function.IsAsync) {
-					entityDecl.Modifiers |= Modifiers.Async;
-					RemoveAttribute(entityDecl, KnownAttribute.AsyncStateMachine);
-					RemoveAttribute(entityDecl, KnownAttribute.DebuggerStepThrough);
+					RemoveAttribute(entityDecl, KnownAttribute.AsyncIteratorStateMachine);
+				} else {
+					RemoveAttribute(entityDecl, KnownAttribute.IteratorStateMachine);
 				}
-			} catch (Exception innerException) when (!(innerException is OperationCanceledException || innerException is DecompilerException)) {
-				throw new DecompilerException(module, method, innerException);
+				if (function.StateMachineCompiledWithMono) {
+					RemoveAttribute(entityDecl, KnownAttribute.DebuggerHidden);
+				}
+			}
+			if (function.IsAsync) {
+				entityDecl.Modifiers |= Modifiers.Async;
+				RemoveAttribute(entityDecl, KnownAttribute.AsyncStateMachine);
+				RemoveAttribute(entityDecl, KnownAttribute.DebuggerStepThrough);
 			}
 		}
 
-		bool RemoveAttribute(EntityDeclaration entityDecl, KnownAttribute attributeType)
+		internal static bool RemoveAttribute(EntityDeclaration entityDecl, KnownAttribute attributeType)
 		{
 			bool found = false;
 			foreach (var section in entityDecl.Attributes) {

ICSharpCode.Decompiler/CSharp/CallBuilder.cs

@@ -197,8 +197,7 @@ namespace ICSharpCode.Decompiler.CSharp
 			} else if (localFunction != null) {
 				var ide = new IdentifierExpression(localFunction.Name);
 				if (method.TypeArguments.Count > 0) {
-					int skipCount = localFunction.ReducedMethod.NumberOfCompilerGeneratedTypeParameters;
-					ide.TypeArguments.AddRange(method.TypeArguments.Skip(skipCount).Select(expressionBuilder.ConvertType));
+					ide.TypeArguments.AddRange(method.TypeArguments.Select(expressionBuilder.ConvertType));
 				}
 				ide.AddAnnotation(localFunction);
 				target = ide.WithoutILInstruction()
@@ -1327,7 +1326,6 @@ namespace ICSharpCode.Decompiler.CSharp
 				target = default;
 				targetType = default;
 				methodName = localFunction.Name;
-				// TODO : think about how to handle generic local functions
 			} else if (method.IsExtensionMethod && invokeMethod != null && method.Parameters.Count - 1 == invokeMethod.Parameters.Count) {
 				step = 5;
 				targetType = method.Parameters[0].Type;
@@ -1406,11 +1404,7 @@ namespace ICSharpCode.Decompiler.CSharp
 			} else {
 				var ide = new IdentifierExpression(methodName);
 				if ((step & 2) != 0) {
-					int skipCount = 0;
-					if (localFunction != null && method.TypeArguments.Count > 0) {
-						skipCount = localFunction.ReducedMethod.NumberOfCompilerGeneratedTypeParameters;
-					}
-					ide.TypeArguments.AddRange(method.TypeArguments.Skip(skipCount).Select(expressionBuilder.ConvertType));
+					ide.TypeArguments.AddRange(method.TypeArguments.Select(expressionBuilder.ConvertType));
 				}
 				targetExpression = ide.WithRR(result);
 			}
@@ -1469,7 +1463,7 @@ namespace ICSharpCode.Decompiler.CSharp
 						method.DeclaringType,
 						new IParameterizedMember[] { method }
 					)
-				}, method.TypeArguments.Skip(localFunction.ReducedMethod.NumberOfCompilerGeneratedTypeParameters).ToArray()
+				}, method.TypeArguments
 			);
 		}
 

ICSharpCode.Decompiler/CSharp/ExpressionBuilder.cs

@@ -92,6 +92,7 @@ namespace ICSharpCode.Decompiler.CSharp
 			this.astBuilder = new TypeSystemAstBuilder(resolver);
 			this.astBuilder.AlwaysUseShortTypeNames = true;
 			this.astBuilder.AddResolveResultAnnotations = true;
+			this.astBuilder.ShowAttributes = true;
 			this.astBuilder.UseNullableSpecifierForValueTypes = settings.LiftNullables;
 			this.typeInference = new TypeInference(compilation) { Algorithm = TypeInferenceAlgorithm.Improved };
 		}
@@ -1983,7 +1984,7 @@ namespace ICSharpCode.Decompiler.CSharp
 				return SpecialType.UnknownType;
 		}
 
-		internal IEnumerable<ParameterDeclaration> MakeParameters(IReadOnlyList<IParameter> parameters, ILFunction function)
+		IEnumerable<ParameterDeclaration> MakeParameters(IReadOnlyList<IParameter> parameters, ILFunction function)
 		{
 			var variables = function.Variables.Where(v => v.Kind == VariableKind.Parameter).ToDictionary(v => v.Index);
 			int i = 0;
@@ -1992,9 +1993,6 @@ namespace ICSharpCode.Decompiler.CSharp
 				if (string.IsNullOrEmpty(pd.Name) && !pd.Type.IsArgList()) {
 					// needs to be consistent with logic in ILReader.CreateILVarable(ParameterDefinition)
 					pd.Name = "P_" + i;
-					// if this is a local function, we have to skip the parameters for closure references
-					if (settings.LocalFunctions && function.Kind == ILFunctionKind.LocalFunction && IL.Transforms.LocalFunctionDecompiler.IsClosureParameter(parameter, decompilationContext))
-						break;
 				}
 				if (settings.AnonymousTypes && parameter.Type.ContainsAnonymousType())
 					pd.Type = null;

ICSharpCode.Decompiler/CSharp/OutputVisitor/CSharpOutputVisitor.cs

@@ -1876,19 +1876,7 @@ namespace ICSharpCode.Decompiler.CSharp.OutputVisitor
 		public virtual void VisitLocalFunctionDeclarationStatement(LocalFunctionDeclarationStatement localFunctionDeclarationStatement)
 		{
 			StartNode(localFunctionDeclarationStatement);
-
-			WriteModifiers(localFunctionDeclarationStatement.ModifierTokens);
-			localFunctionDeclarationStatement.ReturnType.AcceptVisitor(this);
-			Space();
-			WriteIdentifier(localFunctionDeclarationStatement.NameToken);
-			WriteTypeParameters(localFunctionDeclarationStatement.TypeParameters);
-			Space(policy.SpaceBeforeMethodDeclarationParentheses);
-			WriteCommaSeparatedListInParenthesis(localFunctionDeclarationStatement.Parameters, policy.SpaceWithinMethodDeclarationParentheses);
-			foreach (Constraint constraint in localFunctionDeclarationStatement.Constraints) {
-				constraint.AcceptVisitor(this);
-			}
-			WriteMethodBody(localFunctionDeclarationStatement.Body, policy.MethodBraceStyle);
-
+			localFunctionDeclarationStatement.Declaration.AcceptVisitor(this);
 			EndNode(localFunctionDeclarationStatement);
 		}
 

ICSharpCode.Decompiler/CSharp/StatementBuilder.cs

@@ -1002,34 +1002,19 @@ namespace ICSharpCode.Decompiler.CSharp
 
 			LocalFunctionDeclarationStatement TranslateFunction(ILFunction function)
 			{
-				var stmt = new LocalFunctionDeclarationStatement();
 				var nestedBuilder = new StatementBuilder(typeSystem, exprBuilder.decompilationContext, function, settings, cancellationToken);
-				stmt.Name = function.Name;
-				stmt.Parameters.AddRange(exprBuilder.MakeParameters(function.Parameters, function));
-				stmt.ReturnType = exprBuilder.ConvertType(function.Method.ReturnType);
-				stmt.Body = nestedBuilder.ConvertAsBlock(function.Body);
+				var astBuilder = exprBuilder.astBuilder;
+				var method = (MethodDeclaration)astBuilder.ConvertEntity(function.ReducedMethod);
+				method.Body = nestedBuilder.ConvertAsBlock(function.Body);
 
 				Comment prev = null;
 				foreach (string warning in function.Warnings) {
-					stmt.Body.InsertChildAfter(prev, prev = new Comment(warning), Roles.Comment);
+					method.Body.InsertChildAfter(prev, prev = new Comment(warning), Roles.Comment);
 				}
 
-				if (function.Method.TypeParameters.Count > 0) {
-					var astBuilder = exprBuilder.astBuilder;
-					if (astBuilder.ShowTypeParameters) {
-						int skipCount = function.ReducedMethod.NumberOfCompilerGeneratedTypeParameters;
-						stmt.TypeParameters.AddRange(function.Method.TypeParameters.Skip(skipCount).Select(t => astBuilder.ConvertTypeParameter(t)));
-						if (astBuilder.ShowTypeParameterConstraints) {
-							stmt.Constraints.AddRange(function.Method.TypeParameters.Skip(skipCount).Select(t => astBuilder.ConvertTypeParameterConstraint(t)).Where(c => c != null));
-						}
-					}
-				}
-				if (function.IsAsync) {
-					stmt.Modifiers |= Modifiers.Async;
-				}
-				if (settings.StaticLocalFunctions && function.ReducedMethod.IsStaticLocalFunction) {
-					stmt.Modifiers |= Modifiers.Static;
-				}
+				CSharpDecompiler.CleanUpMethodDeclaration(method, method.Body, function);
+				CSharpDecompiler.RemoveAttribute(method, KnownAttribute.CompilerGenerated);
+				var stmt = new LocalFunctionDeclarationStatement(method);
 				stmt.AddAnnotation(new MemberResolveResult(null, function.ReducedMethod));
 				stmt.WithILInstruction(function);
 				return stmt;

ICSharpCode.Decompiler/CSharp/Syntax/Statements/LocalFunctionDeclarationStatement.cs

@@ -16,69 +16,22 @@
 // OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 // DEALINGS IN THE SOFTWARE.
 
-using System.Collections.Generic;
 using ICSharpCode.Decompiler.CSharp.Syntax.PatternMatching;
 
 namespace ICSharpCode.Decompiler.CSharp.Syntax
 {
 	public class LocalFunctionDeclarationStatement : Statement
 	{
-		public AstNodeCollection<TypeParameterDeclaration> TypeParameters {
-			get { return GetChildrenByRole(Roles.TypeParameter); }
-		}
-
-		public CSharpTokenNode LParToken {
-			get { return GetChildByRole(Roles.LPar); }
-		}
-
-		public AstNodeCollection<ParameterDeclaration> Parameters {
-			get { return GetChildrenByRole(Roles.Parameter); }
-		}
+		public static readonly Role<MethodDeclaration> MethodDeclarationRole = new Role<MethodDeclaration>("Method");
 
-		public CSharpTokenNode RParToken {
-			get { return GetChildByRole(Roles.RPar); }
+		public MethodDeclaration Declaration {
+			get { return GetChildByRole(MethodDeclarationRole); }
+			set { SetChildByRole(MethodDeclarationRole, value); }
 		}
 
-		public AstNodeCollection<Constraint> Constraints {
-			get { return GetChildrenByRole(Roles.Constraint); }
-		}
-
-		public BlockStatement Body {
-			get { return GetChildByRole(Roles.Body); }
-			set { SetChildByRole(Roles.Body, value); }
-		}
-
-		public Modifiers Modifiers {
-			get { return EntityDeclaration.GetModifiers(this); }
-			set { EntityDeclaration.SetModifiers(this, value); }
-		}
-
-		public bool HasModifier(Modifiers mod)
+		public LocalFunctionDeclarationStatement(MethodDeclaration methodDeclaration)
 		{
-			return (Modifiers & mod) == mod;
-		}
-
-		public IEnumerable<CSharpModifierToken> ModifierTokens {
-			get { return GetChildrenByRole(EntityDeclaration.ModifierRole); }
-		}
-
-		public virtual string Name {
-			get {
-				return GetChildByRole(Roles.Identifier).Name;
-			}
-			set {
-				SetChildByRole(Roles.Identifier, Identifier.Create(value, TextLocation.Empty));
-			}
-		}
-
-		public virtual Identifier NameToken {
-			get { return GetChildByRole(Roles.Identifier); }
-			set { SetChildByRole(Roles.Identifier, value); }
-		}
-
-		public virtual AstType ReturnType {
-			get { return GetChildByRole(Roles.Type); }
-			set { SetChildByRole(Roles.Type, value); }
+			AddChild(methodDeclaration, MethodDeclarationRole);
 		}
 
 		public override void AcceptVisitor(IAstVisitor visitor)
@@ -98,13 +51,7 @@ namespace ICSharpCode.Decompiler.CSharp.Syntax
 
 		protected internal override bool DoMatch(AstNode other, Match match)
 		{
-			LocalFunctionDeclarationStatement o = other as LocalFunctionDeclarationStatement;
-			return o != null && MatchString(this.Name, o.Name)
-				&& (this.Modifiers == Modifiers.Any || this.Modifiers == o.Modifiers)
-				&& this.ReturnType.DoMatch(o.ReturnType, match)
-				&& this.TypeParameters.DoMatch(o.TypeParameters, match)
-				&& this.Parameters.DoMatch(o.Parameters, match) && this.Constraints.DoMatch(o.Constraints, match)
-				&& this.Body.DoMatch(o.Body, match);
+			return other is LocalFunctionDeclarationStatement o && Declaration.DoMatch(o.Declaration, match);
 		}
 	}
 }

ICSharpCode.Decompiler/CSharp/Syntax/TypeSystemAstBuilder.cs

@@ -1799,6 +1799,8 @@ namespace ICSharpCode.Decompiler.CSharp.Syntax
 					return !member.IsStatic;
 				case SymbolKind.Destructor:
 					return false;
+				case SymbolKind.Method:
+					return !((IMethod)member).IsLocalFunction;
 				default:
 					return true;
 			}
@@ -1811,7 +1813,11 @@ namespace ICSharpCode.Decompiler.CSharp.Syntax
 				m |= ModifierFromAccessibility (member.Accessibility);
 			}
 			if (this.ShowModifiers) {
-				if (member.IsStatic) {
+				if (member is LocalFunctionMethod localFunction) {
+					if (localFunction.IsStaticLocalFunction) {
+						m |= Modifiers.Static;
+					}
+				} else if (member.IsStatic) {
 					m |= Modifiers.Static;
 				} else {
 					var declaringType = member.DeclaringType;

ICSharpCode.Decompiler/CSharp/Transforms/ContextTrackingVisitor.cs

@@ -55,56 +55,56 @@ namespace ICSharpCode.Decompiler.CSharp.Transforms
 		
 		public override TResult VisitMethodDeclaration(MethodDeclaration methodDeclaration)
 		{
-			Debug.Assert(currentMethod == null);
+			var oldMethod = currentMethod;
 			try {
 				currentMethod = methodDeclaration.GetSymbol() as IMethod;
 				return base.VisitMethodDeclaration(methodDeclaration);
 			} finally {
-				currentMethod = null;
+				currentMethod = oldMethod;
 			}
 		}
 		
 		public override TResult VisitConstructorDeclaration(ConstructorDeclaration constructorDeclaration)
 		{
-			Debug.Assert(currentMethod == null);
+			var oldMethod = currentMethod;
 			try {
 				currentMethod = constructorDeclaration.GetSymbol() as IMethod;
 				return base.VisitConstructorDeclaration(constructorDeclaration);
 			} finally {
-				currentMethod = null;
+				currentMethod = oldMethod;
 			}
 		}
 		
 		public override TResult VisitDestructorDeclaration(DestructorDeclaration destructorDeclaration)
 		{
-			Debug.Assert(currentMethod == null);
+			var oldMethod = currentMethod;
 			try {
 				currentMethod = destructorDeclaration.GetSymbol() as IMethod;
 				return base.VisitDestructorDeclaration(destructorDeclaration);
 			} finally {
-				currentMethod = null;
+				currentMethod = oldMethod;
 			}
 		}
 		
 		public override TResult VisitOperatorDeclaration(OperatorDeclaration operatorDeclaration)
 		{
-			Debug.Assert(currentMethod == null);
+			var oldMethod = currentMethod;
 			try {
 				currentMethod = operatorDeclaration.GetSymbol() as IMethod;
 				return base.VisitOperatorDeclaration(operatorDeclaration);
 			} finally {
-				currentMethod = null;
+				currentMethod = oldMethod;
 			}
 		}
 		
 		public override TResult VisitAccessor(Accessor accessor)
 		{
-			Debug.Assert(currentMethod == null);
+			var oldMethod = currentMethod;
 			try {
 				currentMethod = accessor.GetSymbol() as IMethod;
 				return base.VisitAccessor(accessor);
 			} finally {
-				currentMethod = null;
+				currentMethod = oldMethod;
 			}
 		}
 	}

ICSharpCode.Decompiler/IL/Transforms/LocalFunctionDecompiler.cs

@@ -484,7 +484,7 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 					break;
 				parametersToRemove++;
 			}
-			return new LocalFunctionMethod(method, parametersToRemove, typeParametersToRemove);
+			return new LocalFunctionMethod(method, method.Name, parametersToRemove, typeParametersToRemove);
 		}
 
 		static void TransformToLocalFunctionReference(ILFunction function, CallInstruction useSite)

ICSharpCode.Decompiler/TypeSystem/Implementation/LocalFunctionMethod.cs

@@ -31,11 +31,12 @@ namespace ICSharpCode.Decompiler.TypeSystem.Implementation
 	{
 		readonly IMethod baseMethod;
 
-		public LocalFunctionMethod(IMethod baseMethod, int numberOfCompilerGeneratedParameters, int numberOfCompilerGeneratedTypeParameters)
+		public LocalFunctionMethod(IMethod baseMethod, string name, int numberOfCompilerGeneratedParameters, int numberOfCompilerGeneratedTypeParameters)
 		{
 			if (baseMethod == null)
 				throw new ArgumentNullException(nameof(baseMethod));
 			this.baseMethod = baseMethod;
+			this.Name = name;
 			this.NumberOfCompilerGeneratedParameters = numberOfCompilerGeneratedParameters;
 			this.NumberOfCompilerGeneratedTypeParameters = numberOfCompilerGeneratedTypeParameters;
 		}
@@ -65,7 +66,7 @@ namespace ICSharpCode.Decompiler.TypeSystem.Implementation
 
 		public override string ToString()
 		{
-			return string.Format("[LocalFunctionMethod: ReducedFrom={0}, NumberOfGeneratedParameters={1}, NumberOfCompilerGeneratedTypeParameters={2}]", ReducedFrom, NumberOfCompilerGeneratedParameters, NumberOfCompilerGeneratedTypeParameters);
+			return string.Format("[LocalFunctionMethod: ReducedFrom={0}, Name={1}, NumberOfGeneratedParameters={2}, NumberOfCompilerGeneratedTypeParameters={3}]", ReducedFrom, Name, NumberOfCompilerGeneratedParameters, NumberOfCompilerGeneratedTypeParameters);
 		}
 
 		internal int NumberOfCompilerGeneratedParameters { get; }
@@ -88,7 +89,7 @@ namespace ICSharpCode.Decompiler.TypeSystem.Implementation
 		{
 			return new LocalFunctionMethod(
 				baseMethod.Specialize(substitution),
-				NumberOfCompilerGeneratedParameters, NumberOfCompilerGeneratedTypeParameters);
+				Name, NumberOfCompilerGeneratedParameters, NumberOfCompilerGeneratedTypeParameters);
 		}
 		
 		IMember IMember.Specialize(TypeParameterSubstitution substitution)
@@ -96,7 +97,6 @@ namespace ICSharpCode.Decompiler.TypeSystem.Implementation
 			return Specialize(substitution);
 		}
 
-		public IReadOnlyList<ITypeParameter> TypeParameters => baseMethod.TypeParameters;
 		public bool IsExtensionMethod => baseMethod.IsExtensionMethod;
 		public bool IsLocalFunction => true;
 		public bool IsConstructor => baseMethod.IsConstructor;
@@ -107,7 +107,24 @@ namespace ICSharpCode.Decompiler.TypeSystem.Implementation
 		public IMember AccessorOwner => baseMethod.AccessorOwner;
 		public MethodSemanticsAttributes AccessorKind => baseMethod.AccessorKind;
 		public IMethod ReducedFrom => baseMethod;
-		public IReadOnlyList<IType> TypeArguments => baseMethod.TypeArguments;
+
+		List<ITypeParameter> typeParameters;
+		public IReadOnlyList<ITypeParameter> TypeParameters {
+			get {
+				if (typeParameters == null)
+					typeParameters = new List<ITypeParameter>(baseMethod.TypeParameters.Skip(NumberOfCompilerGeneratedTypeParameters));
+				return typeParameters;
+			}
+		}
+
+		List<IType> typeArguments;
+		public IReadOnlyList<IType> TypeArguments {
+			get {
+				if (typeArguments == null)
+					typeArguments = new List<IType>(baseMethod.TypeArguments.Skip(NumberOfCompilerGeneratedTypeParameters));
+				return typeArguments;
+			}
+		}
 
 		List<IParameter> parameters;
 		public IReadOnlyList<IParameter> Parameters {
@@ -137,8 +154,8 @@ namespace ICSharpCode.Decompiler.TypeSystem.Implementation
 
 		public Accessibility Accessibility => baseMethod.Accessibility;
 
-		public string FullName => baseMethod.FullName;
-		public string Name => baseMethod.Name;
+		public string FullName => Name;
+		public string Name { get; set; }
 		public string ReflectionName => baseMethod.ReflectionName;
 		public string Namespace => baseMethod.Namespace;