Add IOperation unit tests for try/catch statements and make the APIs public again

Fixes #22008

There might be some more API changes based on the open issues mentioned in #22008

src/Compilers/CSharp/Portable/Operations/CSharpOperationFactory.cs

@@ -304,8 +304,13 @@ private IInvocationExpression CreateBoundCallOperation(BoundCall boundCall)
             return new LazyInvocationExpression(targetMethod, instance, isVirtual, argumentsInEvaluationOrder, _semanticModel, syntax, type, constantValue, isImplicit);
         }
 
-        private ILocalReferenceExpression CreateBoundLocalOperation(BoundLocal boundLocal)
+        private IOperation CreateBoundLocalOperation(BoundLocal boundLocal)
         {
+            if (boundLocal.Syntax.Kind() == SyntaxKind.CatchDeclaration)
+            {
+                return CreateVariableDeclaration(boundLocal);
+            }
+
             ILocalSymbol local = boundLocal.LocalSymbol;
             bool isDeclaration = boundLocal.IsDeclaration;
             SyntaxNode syntax = boundLocal.Syntax;
@@ -1096,8 +1101,7 @@ private IBlockStatement CreateBoundBlockOperation(BoundBlock boundBlock)
                                                                                 // Filter out all OperationKind.None except fixed statements for now.
                                                                                 // https://github.com/dotnet/roslyn/issues/21776
                                                                                 .Where(s => s.operation.Kind != OperationKind.None ||
-                                                                                s.bound.Kind == BoundKind.FixedStatement ||
-                                                                                s.bound.Kind == BoundKind.TryStatement)
+                                                                                s.bound.Kind == BoundKind.FixedStatement)
                                                                                 .Select(s => s.operation).ToImmutableArray());
 
             ImmutableArray<ILocalSymbol> locals = boundBlock.Locals.As<ILocalSymbol>();
@@ -1284,15 +1288,15 @@ private ITryStatement CreateBoundTryStatementOperation(BoundTryStatement boundTr
 
         private ICatchClause CreateBoundCatchBlockOperation(BoundCatchBlock boundCatchBlock)
         {
-            Lazy<IBlockStatement> handler = new Lazy<IBlockStatement>(() => (IBlockStatement)Create(boundCatchBlock.Body));
-            ITypeSymbol caughtType = boundCatchBlock.ExceptionTypeOpt;
+            Lazy<IOperation> expressionDeclarationOrExpression = new Lazy<IOperation>(() => boundCatchBlock.ExceptionSourceOpt != null ? Create(boundCatchBlock.ExceptionSourceOpt) : null);
+            ITypeSymbol exceptionType = boundCatchBlock.ExceptionTypeOpt ?? ((CSharpCompilation)_semanticModel.Compilation).GetWellKnownType(WellKnownType.System_Exception);
             Lazy<IOperation> filter = new Lazy<IOperation>(() => Create(boundCatchBlock.ExceptionFilterOpt));
-            ILocalSymbol exceptionLocal = (boundCatchBlock.Locals.FirstOrDefault()?.DeclarationKind == CSharp.Symbols.LocalDeclarationKind.CatchVariable) ? boundCatchBlock.Locals.FirstOrDefault() : null;
+            Lazy<IBlockStatement> handler = new Lazy<IBlockStatement>(() => (IBlockStatement)Create(boundCatchBlock.Body));
             SyntaxNode syntax = boundCatchBlock.Syntax;
             ITypeSymbol type = null;
             Optional<object> constantValue = default(Optional<object>);
             bool isImplicit = boundCatchBlock.WasCompilerGenerated;
-            return new LazyCatchClause(handler, caughtType, filter, exceptionLocal, _semanticModel, syntax, type, constantValue, isImplicit);
+            return new LazyCatchClause(expressionDeclarationOrExpression, exceptionType, filter, handler, _semanticModel, syntax, type, constantValue, isImplicit);
         }
 
         private IFixedStatement CreateBoundFixedStatementOperation(BoundFixedStatement boundFixedStatement)

src/Compilers/CSharp/Portable/Operations/CSharpOperationFactory_Methods.cs

@@ -56,6 +56,11 @@ private IVariableDeclaration CreateVariableDeclaration(BoundLocalDeclaration bou
             return OperationFactory.CreateVariableDeclaration(boundLocalDeclaration.LocalSymbol, Create(boundLocalDeclaration.InitializerOpt), _semanticModel, syntax);
         }
 
+        private IVariableDeclaration CreateVariableDeclaration(BoundLocal boundLocal)
+        {
+            return OperationFactory.CreateVariableDeclaration(boundLocal.LocalSymbol, initialValue: null, semanticModel: _semanticModel, syntax: boundLocal.Syntax);
+        }
+
         private IOperation CreateBoundCallInstanceOperation(BoundCall boundCall)
         {
             if (boundCall.Method == null || boundCall.Method.IsStatic)

src/Compilers/CSharp/Test/Semantic/IOperation/IOperationTests_IWhileUntilLoopStatement.cs

@@ -896,7 +896,7 @@ public void TryMethod()
               Target: ILocalReferenceExpression: x (OperationKind.LocalReferenceExpression, Type: System.SByte) (Syntax: 'x')
       Right: ILiteralExpression (OperationKind.LiteralExpression, Type: System.Int32, Constant: 0) (Syntax: '0')
   Body: IBlockStatement (1 statements) (OperationKind.BlockStatement) (Syntax: '{ ... }')
-      ITryStatement (OperationKind.None) (Syntax: 'try ... }')
+      ITryStatement (OperationKind.TryStatement) (Syntax: 'try ... }')
         Body: IBlockStatement (1 statements) (OperationKind.BlockStatement) (Syntax: '{ ... }')
             IExpressionStatement (OperationKind.ExpressionStatement) (Syntax: 'y = (sbyte)(x / 2);')
               Expression: ISimpleAssignmentExpression (OperationKind.SimpleAssignmentExpression, Type: System.SByte) (Syntax: 'y = (sbyte)(x / 2)')

src/Compilers/Core/Portable/Generated/Operations.xml.Generated.cs

@@ -827,41 +827,44 @@ internal abstract partial class CaseClause : Operation, ICaseClause
     /// </summary>
     internal abstract partial class BaseCatchClause : Operation, ICatchClause
     {
-        protected BaseCatchClause(ITypeSymbol caughtType, ILocalSymbol exceptionLocal, SemanticModel semanticModel, SyntaxNode syntax, ITypeSymbol type, Optional<object> constantValue, bool isImplicit) :
-            // https://github.com/dotnet/roslyn/issues/22008   
-            // base(OperationKind.CatchClause, semanticModel, syntax, type, constantValue, isImplicit)
-            base(OperationKind.None, semanticModel, syntax, type, constantValue, isImplicit)
+        protected BaseCatchClause(ITypeSymbol exceptionType, SemanticModel semanticModel, SyntaxNode syntax, ITypeSymbol type, Optional<object> constantValue, bool isImplicit) :
+            base(OperationKind.CatchClause, semanticModel, syntax, type, constantValue, isImplicit)
         {
-            CaughtType = caughtType;
-            ExceptionLocal = exceptionLocal;
+            ExceptionType = exceptionType;
         }
-
-        protected abstract IBlockStatement HandlerImpl { get; }
         /// <summary>
-        /// Type of exception to be handled.
+        /// Type of the exception handled by the catch clause.
         /// </summary>
-        public ITypeSymbol CaughtType { get; }
+        public ITypeSymbol ExceptionType { get; }
+        protected abstract IOperation ExceptionDeclarationOrExpressionImpl { get; }
         protected abstract IOperation FilterImpl { get; }
-        /// <summary>
-        /// Symbol for the local catch variable bound to the caught exception.
-        /// </summary>
-        public ILocalSymbol ExceptionLocal { get; }
+        protected abstract IBlockStatement HandlerImpl { get; }
         public override IEnumerable<IOperation> Children
         {
             get
             {
+                yield return ExceptionDeclarationOrExpression;
                 yield return Filter;
                 yield return Handler;
             }
         }
         /// <summary>
-        /// Body of the exception handler.
+        /// Optional source for exception. This could be any of the following operation:
+        /// 1. Declaration for the local catch variable bound to the caught exception (C# and VB) OR
+        /// 2. Type expression for the caught expression type (C#) OR
+        /// 3. Null, indicating no expression (C#)
+        /// 4. Reference to an existing local or parameter (VB) OR
+        /// 5. An error expression (VB)
         /// </summary>
-        public IBlockStatement Handler => Operation.SetParentOperation(HandlerImpl, this);
+        public IOperation ExceptionDeclarationOrExpression => Operation.SetParentOperation(ExceptionDeclarationOrExpressionImpl, this);
         /// <summary>
         /// Filter expression to be executed to determine whether to handle the exception.
         /// </summary>
         public IOperation Filter => Operation.SetParentOperation(FilterImpl, this);
+        /// <summary>
+        /// Body of the exception handler.
+        /// </summary>
+        public IBlockStatement Handler => Operation.SetParentOperation(HandlerImpl, this);
         public override void Accept(OperationVisitor visitor)
         {
             visitor.VisitCatchClause(this);
@@ -877,15 +880,17 @@ public override void Accept(OperationVisitor visitor)
     /// </summary>
     internal sealed partial class CatchClause : BaseCatchClause, ICatchClause
     {
-        public CatchClause(IBlockStatement handler, ITypeSymbol caughtType, IOperation filter, ILocalSymbol exceptionLocal, SemanticModel semanticModel, SyntaxNode syntax, ITypeSymbol type, Optional<object> constantValue, bool isImplicit) :
-            base(caughtType, exceptionLocal, semanticModel, syntax, type, constantValue, isImplicit)
+        public CatchClause(IOperation exceptionDeclarationOrExpression, ITypeSymbol exceptionType, IOperation filter, IBlockStatement handler, SemanticModel semanticModel, SyntaxNode syntax, ITypeSymbol type, Optional<object> constantValue, bool isImplicit) :
+            base(exceptionType, semanticModel, syntax, type, constantValue, isImplicit)
         {
-            HandlerImpl = handler;
+            ExceptionDeclarationOrExpressionImpl = exceptionDeclarationOrExpression;
             FilterImpl = filter;
+            HandlerImpl = handler;
         }
 
         protected override IBlockStatement HandlerImpl { get; }
         protected override IOperation FilterImpl { get; }
+        protected override IOperation ExceptionDeclarationOrExpressionImpl { get; }
     }
 
     /// <summary>
@@ -893,18 +898,21 @@ internal sealed partial class CatchClause : BaseCatchClause, ICatchClause
     /// </summary>
     internal sealed partial class LazyCatchClause : BaseCatchClause, ICatchClause
     {
-        private readonly Lazy<IBlockStatement> _lazyHandler;
+        private readonly Lazy<IOperation> _lazyExceptionDeclarationOrExpression;
         private readonly Lazy<IOperation> _lazyFilter;
+        private readonly Lazy<IBlockStatement> _lazyHandler;
 
-        public LazyCatchClause(Lazy<IBlockStatement> handler, ITypeSymbol caughtType, Lazy<IOperation> filter, ILocalSymbol exceptionLocal, SemanticModel semanticModel, SyntaxNode syntax, ITypeSymbol type, Optional<object> constantValue, bool isImplicit) : base(caughtType, exceptionLocal, semanticModel, syntax, type, constantValue, isImplicit)
+        public LazyCatchClause(Lazy<IOperation> exceptionDeclarationOrExpression, ITypeSymbol exceptionType, Lazy<IOperation> filter, Lazy<IBlockStatement> handler, SemanticModel semanticModel, SyntaxNode syntax, ITypeSymbol type, Optional<object> constantValue, bool isImplicit)
+            : base(exceptionType, semanticModel, syntax, type, constantValue, isImplicit)
         {
-            _lazyHandler = handler ?? throw new System.ArgumentNullException(nameof(handler));
+            _lazyExceptionDeclarationOrExpression = exceptionDeclarationOrExpression ?? throw new System.ArgumentNullException(nameof(exceptionDeclarationOrExpression));
             _lazyFilter = filter ?? throw new System.ArgumentNullException(nameof(filter));
+            _lazyHandler = handler ?? throw new System.ArgumentNullException(nameof(handler));
         }
 
-        protected override IBlockStatement HandlerImpl => _lazyHandler.Value;
-
+        protected override IOperation ExceptionDeclarationOrExpressionImpl => _lazyExceptionDeclarationOrExpression.Value;
         protected override IOperation FilterImpl => _lazyFilter.Value;
+        protected override IBlockStatement HandlerImpl => _lazyHandler.Value;
     }
 
     /// <summary>
@@ -4338,9 +4346,7 @@ internal abstract partial class SymbolInitializer : Operation, ISymbolInitialize
     internal abstract partial class BaseTryStatement : Operation, ITryStatement
     {
         protected BaseTryStatement(SemanticModel semanticModel, SyntaxNode syntax, ITypeSymbol type, Optional<object> constantValue, bool isImplicit) :
-            // https://github.com/dotnet/roslyn/issues/22008
-            // base(OperationKind.TryStatement, semanticModel, syntax, type, constantValue, isImplicit)
-            base(OperationKind.None, semanticModel, syntax, type, constantValue, isImplicit)
+            base(OperationKind.TryStatement, semanticModel, syntax, type, constantValue, isImplicit)
         {
         }
 

src/Compilers/Core/Portable/Operations/ICatchClause.cs

 // Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
-using System.Collections.Immutable;
-
 namespace Microsoft.CodeAnalysis.Semantics
 {
     /// <summary>
@@ -11,24 +9,31 @@ namespace Microsoft.CodeAnalysis.Semantics
     /// This interface is reserved for implementation by its associated APIs. We reserve the right to
     /// change it in the future.
     /// </remarks>
-    internal interface ICatchClause : IOperation // https://github.com/dotnet/roslyn/issues/22008
+    public interface ICatchClause : IOperation
     {
         /// <summary>
         /// Body of the exception handler.
         /// </summary>
         IBlockStatement Handler { get; }
+
         /// <summary>
-        /// Type of exception to be handled.
+        /// Type of the exception handled by the catch clause.
         /// </summary>
-        ITypeSymbol CaughtType { get; }
+        ITypeSymbol ExceptionType { get; }
+
         /// <summary>
-        /// Filter expression to be executed to determine whether to handle the exception.
+        /// Optional source for exception. This could be any of the following operation:
+        /// 1. Declaration for the local catch variable bound to the caught exception (C# and VB) OR
+        /// 2. Null, indicating no declaration or expression (C# and VB)
+        /// 3. Reference to an existing local or parameter (VB) OR
+        /// 4. An error expression (VB)
         /// </summary>
-        IOperation Filter { get; }
+        IOperation ExceptionDeclarationOrExpression { get; }
+
         /// <summary>
-        /// Symbol for the local catch variable bound to the caught exception.
+        /// Filter expression to be executed to determine whether to handle the exception.
         /// </summary>
-        ILocalSymbol ExceptionLocal { get; }
+        IOperation Filter { get; }
     }
 }
 

src/Compilers/Core/Portable/Operations/ITryStatement.cs

@@ -11,7 +11,7 @@ namespace Microsoft.CodeAnalysis.Semantics
     /// This interface is reserved for implementation by its associated APIs. We reserve the right to
     /// change it in the future.
     /// </remarks>
-    internal interface ITryStatement : IOperation // https://github.com/dotnet/roslyn/issues/22008
+    public interface ITryStatement : IOperation
     {
         /// <summary>
         /// Body of the try, over which the handlers are active.

src/Compilers/Core/Portable/Operations/OperationCloner.cs

@@ -139,14 +139,14 @@ public override IOperation VisitLockStatement(ILockStatement operation, object a
             return new LockStatement(Visit(operation.Expression), Visit(operation.Body), ((Operation)operation).SemanticModel, operation.Syntax, operation.Type, operation.ConstantValue, operation.IsImplicit);
         }
 
-        internal override IOperation VisitTryStatement(ITryStatement operation, object argument)
+        public override IOperation VisitTryStatement(ITryStatement operation, object argument)
         {
             return new TryStatement(Visit(operation.Body), VisitArray(operation.Catches), Visit(operation.FinallyHandler), ((Operation)operation).SemanticModel, operation.Syntax, operation.Type, operation.ConstantValue, operation.IsImplicit);
         }
 
-        internal override IOperation VisitCatchClause(ICatchClause operation, object argument)
+        public override IOperation VisitCatchClause(ICatchClause operation, object argument)
         {
-            return new CatchClause(Visit(operation.Handler), operation.CaughtType, Visit(operation.Filter), operation.ExceptionLocal, ((Operation)operation).SemanticModel, operation.Syntax, operation.Type, operation.ConstantValue, operation.IsImplicit);
+            return new CatchClause(Visit(operation.ExceptionDeclarationOrExpression), operation.ExceptionType, Visit(operation.Filter), Visit(operation.Handler), ((Operation)operation).SemanticModel, operation.Syntax, operation.Type, operation.ConstantValue, operation.IsImplicit);
         }
 
         public override IOperation VisitUsingStatement(IUsingStatement operation, object argument)

src/Compilers/Core/Portable/Operations/OperationKind.cs

@@ -38,9 +38,8 @@ public enum OperationKind
         YieldBreakStatement = 0xc,
         /// <summary>Indicates an <see cref="ILockStatement"/>.</summary>
         LockStatement = 0xd,
-        // https://github.com/dotnet/roslyn/issues/22008
-        // /// <summary>Indicates an <see cref="ITryStatement"/>.</summary>
-        // TryStatement = 0xe,
+        /// <summary>Indicates an <see cref="ITryStatement"/>.</summary>
+        TryStatement = 0xe,
         /// <summary>Indicates an <see cref="IUsingStatement"/>.</summary>
         UsingStatement = 0xf,
         /// <summary>Indicates an <see cref="IReturnStatement"/>.</summary>
@@ -208,9 +207,8 @@ public enum OperationKind
         /// <summary>Indicates an <see cref="IArgument"/>.</summary>
         Argument = 0x407,
 
-        // https://github.com/dotnet/roslyn/issues/22008
-        // /// <summary>Indicates an <see cref="ICatchClause"/>.</summary>
-        // CatchClause = 0x408,
+        /// <summary>Indicates an <see cref="ICatchClause"/>.</summary>
+        CatchClause = 0x408,
 
         /// <summary>Indicates an <see cref="ISwitchCase"/>.</summary>
         SwitchCase = 0x409,

src/Compilers/Core/Portable/Operations/OperationVisitor.cs

@@ -130,14 +130,12 @@ public virtual void VisitLockStatement(ILockStatement operation)
             DefaultVisit(operation);
         }
 
-        // https://github.com/dotnet/roslyn/issues/22008
-        internal virtual void VisitTryStatement(ITryStatement operation)
+        public virtual void VisitTryStatement(ITryStatement operation)
         {
             DefaultVisit(operation);
         }
 
-        // https://github.com/dotnet/roslyn/issues/22008
-        internal virtual void VisitCatchClause(ICatchClause operation)
+        public virtual void VisitCatchClause(ICatchClause operation)
         {
             DefaultVisit(operation);
         }
@@ -626,14 +624,12 @@ public virtual TResult VisitLockStatement(ILockStatement operation, TArgument ar
             return DefaultVisit(operation, argument);
         }
 
-        // https://github.com/dotnet/roslyn/issues/22008
-        internal virtual TResult VisitTryStatement(ITryStatement operation, TArgument argument)
+        public virtual TResult VisitTryStatement(ITryStatement operation, TArgument argument)
         {
             return DefaultVisit(operation, argument);
         }
 
-        // https://github.com/dotnet/roslyn/issues/22008
-        internal virtual TResult VisitCatchClause(ICatchClause operation, TArgument argument)
+        public virtual TResult VisitCatchClause(ICatchClause operation, TArgument argument)
         {
             return DefaultVisit(operation, argument);
         }

src/Compilers/Core/Portable/PublicAPI.Unshipped.txt

@@ -60,6 +60,7 @@ Microsoft.CodeAnalysis.OperationKind.BinaryOperatorExpression = 270 -> Microsoft
 Microsoft.CodeAnalysis.OperationKind.BlockStatement = 2 -> Microsoft.CodeAnalysis.OperationKind
 Microsoft.CodeAnalysis.OperationKind.BranchStatement = 8 -> Microsoft.CodeAnalysis.OperationKind
 Microsoft.CodeAnalysis.OperationKind.CaseClause = 1034 -> Microsoft.CodeAnalysis.OperationKind
+Microsoft.CodeAnalysis.OperationKind.CatchClause = 1032 -> Microsoft.CodeAnalysis.OperationKind
 Microsoft.CodeAnalysis.OperationKind.CoalesceExpression = 272 -> Microsoft.CodeAnalysis.OperationKind
 Microsoft.CodeAnalysis.OperationKind.CollectionElementInitializerExpression = 290 -> Microsoft.CodeAnalysis.OperationKind
 Microsoft.CodeAnalysis.OperationKind.CompoundAssignmentExpression = 281 -> Microsoft.CodeAnalysis.OperationKind
@@ -117,6 +118,7 @@ Microsoft.CodeAnalysis.OperationKind.SwitchCase = 1033 -> Microsoft.CodeAnalysis
 Microsoft.CodeAnalysis.OperationKind.SwitchStatement = 4 -> Microsoft.CodeAnalysis.OperationKind
 Microsoft.CodeAnalysis.OperationKind.ThrowExpression = 519 -> Microsoft.CodeAnalysis.OperationKind
 Microsoft.CodeAnalysis.OperationKind.TranslatedQueryExpression = 297 -> Microsoft.CodeAnalysis.OperationKind
+Microsoft.CodeAnalysis.OperationKind.TryStatement = 14 -> Microsoft.CodeAnalysis.OperationKind
 Microsoft.CodeAnalysis.OperationKind.TupleExpression = 292 -> Microsoft.CodeAnalysis.OperationKind
 Microsoft.CodeAnalysis.OperationKind.TypeOfExpression = 513 -> Microsoft.CodeAnalysis.OperationKind
 Microsoft.CodeAnalysis.OperationKind.TypeParameterObjectCreationExpression = 275 -> Microsoft.CodeAnalysis.OperationKind
@@ -223,6 +225,11 @@ Microsoft.CodeAnalysis.Semantics.IBranchStatement.BranchKind.get -> Microsoft.Co
 Microsoft.CodeAnalysis.Semantics.IBranchStatement.Target.get -> Microsoft.CodeAnalysis.ILabelSymbol
 Microsoft.CodeAnalysis.Semantics.ICaseClause
 Microsoft.CodeAnalysis.Semantics.ICaseClause.CaseKind.get -> Microsoft.CodeAnalysis.Semantics.CaseKind
+Microsoft.CodeAnalysis.Semantics.ICatchClause
+Microsoft.CodeAnalysis.Semantics.ICatchClause.ExceptionDeclarationOrExpression.get -> Microsoft.CodeAnalysis.IOperation
+Microsoft.CodeAnalysis.Semantics.ICatchClause.ExceptionType.get -> Microsoft.CodeAnalysis.ITypeSymbol
+Microsoft.CodeAnalysis.Semantics.ICatchClause.Filter.get -> Microsoft.CodeAnalysis.IOperation
+Microsoft.CodeAnalysis.Semantics.ICatchClause.Handler.get -> Microsoft.CodeAnalysis.Semantics.IBlockStatement
 Microsoft.CodeAnalysis.Semantics.ICoalesceExpression
 Microsoft.CodeAnalysis.Semantics.ICoalesceExpression.Expression.get -> Microsoft.CodeAnalysis.IOperation
 Microsoft.CodeAnalysis.Semantics.ICoalesceExpression.WhenNull.get -> Microsoft.CodeAnalysis.IOperation
@@ -411,6 +418,10 @@ Microsoft.CodeAnalysis.Semantics.IThrowExpression
 Microsoft.CodeAnalysis.Semantics.IThrowExpression.Expression.get -> Microsoft.CodeAnalysis.IOperation
 Microsoft.CodeAnalysis.Semantics.ITranslatedQueryExpression
 Microsoft.CodeAnalysis.Semantics.ITranslatedQueryExpression.Expression.get -> Microsoft.CodeAnalysis.IOperation
+Microsoft.CodeAnalysis.Semantics.ITryStatement
+Microsoft.CodeAnalysis.Semantics.ITryStatement.Body.get -> Microsoft.CodeAnalysis.Semantics.IBlockStatement
+Microsoft.CodeAnalysis.Semantics.ITryStatement.Catches.get -> System.Collections.Immutable.ImmutableArray<Microsoft.CodeAnalysis.Semantics.ICatchClause>
+Microsoft.CodeAnalysis.Semantics.ITryStatement.FinallyHandler.get -> Microsoft.CodeAnalysis.Semantics.IBlockStatement
 Microsoft.CodeAnalysis.Semantics.ITupleExpression
 Microsoft.CodeAnalysis.Semantics.ITupleExpression.Elements.get -> System.Collections.Immutable.ImmutableArray<Microsoft.CodeAnalysis.IOperation>
 Microsoft.CodeAnalysis.Semantics.ITypeOfExpression
@@ -500,6 +511,7 @@ virtual Microsoft.CodeAnalysis.Semantics.OperationVisitor.VisitArrayInitializer(
 virtual Microsoft.CodeAnalysis.Semantics.OperationVisitor.VisitBinaryOperatorExpression(Microsoft.CodeAnalysis.Semantics.IBinaryOperatorExpression operation) -> void
 virtual Microsoft.CodeAnalysis.Semantics.OperationVisitor.VisitBlockStatement(Microsoft.CodeAnalysis.Semantics.IBlockStatement operation) -> void
 virtual Microsoft.CodeAnalysis.Semantics.OperationVisitor.VisitBranchStatement(Microsoft.CodeAnalysis.Semantics.IBranchStatement operation) -> void
+virtual Microsoft.CodeAnalysis.Semantics.OperationVisitor.VisitCatchClause(Microsoft.CodeAnalysis.Semantics.ICatchClause operation) -> void
 virtual Microsoft.CodeAnalysis.Semantics.OperationVisitor.VisitCoalesceExpression(Microsoft.CodeAnalysis.Semantics.ICoalesceExpression operation) -> void
 virtual Microsoft.CodeAnalysis.Semantics.OperationVisitor.VisitCollectionElementInitializerExpression(Microsoft.CodeAnalysis.Semantics.ICollectionElementInitializerExpression operation) -> void
 virtual Microsoft.CodeAnalysis.Semantics.OperationVisitor.VisitCompoundAssignmentExpression(Microsoft.CodeAnalysis.Semantics.ICompoundAssignmentExpression operation) -> void
@@ -563,6 +575,7 @@ virtual Microsoft.CodeAnalysis.Semantics.OperationVisitor.VisitSwitchCase(Micros
 virtual Microsoft.CodeAnalysis.Semantics.OperationVisitor.VisitSwitchStatement(Microsoft.CodeAnalysis.Semantics.ISwitchStatement operation) -> void
 virtual Microsoft.CodeAnalysis.Semantics.OperationVisitor.VisitThrowExpression(Microsoft.CodeAnalysis.Semantics.IThrowExpression operation) -> void
 virtual Microsoft.CodeAnalysis.Semantics.OperationVisitor.VisitTranslatedQueryExpression(Microsoft.CodeAnalysis.Semantics.ITranslatedQueryExpression operation) -> void
+virtual Microsoft.CodeAnalysis.Semantics.OperationVisitor.VisitTryStatement(Microsoft.CodeAnalysis.Semantics.ITryStatement operation) -> void
 virtual Microsoft.CodeAnalysis.Semantics.OperationVisitor.VisitTupleExpression(Microsoft.CodeAnalysis.Semantics.ITupleExpression operation) -> void
 virtual Microsoft.CodeAnalysis.Semantics.OperationVisitor.VisitTypeOfExpression(Microsoft.CodeAnalysis.Semantics.ITypeOfExpression operation) -> void
 virtual Microsoft.CodeAnalysis.Semantics.OperationVisitor.VisitTypeParameterObjectCreationExpression(Microsoft.CodeAnalysis.Semantics.ITypeParameterObjectCreationExpression operation) -> void
@@ -583,6 +596,7 @@ virtual Microsoft.CodeAnalysis.Semantics.OperationVisitor<TArgument, TResult>.Vi
 virtual Microsoft.CodeAnalysis.Semantics.OperationVisitor<TArgument, TResult>.VisitBinaryOperatorExpression(Microsoft.CodeAnalysis.Semantics.IBinaryOperatorExpression operation, TArgument argument) -> TResult
 virtual Microsoft.CodeAnalysis.Semantics.OperationVisitor<TArgument, TResult>.VisitBlockStatement(Microsoft.CodeAnalysis.Semantics.IBlockStatement operation, TArgument argument) -> TResult
 virtual Microsoft.CodeAnalysis.Semantics.OperationVisitor<TArgument, TResult>.VisitBranchStatement(Microsoft.CodeAnalysis.Semantics.IBranchStatement operation, TArgument argument) -> TResult
+virtual Microsoft.CodeAnalysis.Semantics.OperationVisitor<TArgument, TResult>.VisitCatchClause(Microsoft.CodeAnalysis.Semantics.ICatchClause operation, TArgument argument) -> TResult
 virtual Microsoft.CodeAnalysis.Semantics.OperationVisitor<TArgument, TResult>.VisitCoalesceExpression(Microsoft.CodeAnalysis.Semantics.ICoalesceExpression operation, TArgument argument) -> TResult
 virtual Microsoft.CodeAnalysis.Semantics.OperationVisitor<TArgument, TResult>.VisitCollectionElementInitializerExpression(Microsoft.CodeAnalysis.Semantics.ICollectionElementInitializerExpression operation, TArgument argument) -> TResult
 virtual Microsoft.CodeAnalysis.Semantics.OperationVisitor<TArgument, TResult>.VisitCompoundAssignmentExpression(Microsoft.CodeAnalysis.Semantics.ICompoundAssignmentExpression operation, TArgument argument) -> TResult
@@ -646,6 +660,7 @@ virtual Microsoft.CodeAnalysis.Semantics.OperationVisitor<TArgument, TResult>.Vi
 virtual Microsoft.CodeAnalysis.Semantics.OperationVisitor<TArgument, TResult>.VisitSwitchStatement(Microsoft.CodeAnalysis.Semantics.ISwitchStatement operation, TArgument argument) -> TResult
 virtual Microsoft.CodeAnalysis.Semantics.OperationVisitor<TArgument, TResult>.VisitThrowExpression(Microsoft.CodeAnalysis.Semantics.IThrowExpression operation, TArgument argument) -> TResult
 virtual Microsoft.CodeAnalysis.Semantics.OperationVisitor<TArgument, TResult>.VisitTranslatedQueryExpression(Microsoft.CodeAnalysis.Semantics.ITranslatedQueryExpression operation, TArgument argument) -> TResult
+virtual Microsoft.CodeAnalysis.Semantics.OperationVisitor<TArgument, TResult>.VisitTryStatement(Microsoft.CodeAnalysis.Semantics.ITryStatement operation, TArgument argument) -> TResult
 virtual Microsoft.CodeAnalysis.Semantics.OperationVisitor<TArgument, TResult>.VisitTupleExpression(Microsoft.CodeAnalysis.Semantics.ITupleExpression operation, TArgument argument) -> TResult
 virtual Microsoft.CodeAnalysis.Semantics.OperationVisitor<TArgument, TResult>.VisitTypeOfExpression(Microsoft.CodeAnalysis.Semantics.ITypeOfExpression operation, TArgument argument) -> TResult
 virtual Microsoft.CodeAnalysis.Semantics.OperationVisitor<TArgument, TResult>.VisitTypeParameterObjectCreationExpression(Microsoft.CodeAnalysis.Semantics.ITypeParameterObjectCreationExpression operation, TArgument argument) -> TResult

src/Compilers/VisualBasic/Portable/Operations/VisualBasicOperationFactory.vb

@@ -799,7 +799,11 @@ Namespace Microsoft.CodeAnalysis.Semantics
             Return New ParameterReferenceExpression(parameter, _semanticModel, syntax, type, constantValue, isImplicit)
         End Function
 
-        Private Function CreateBoundLocalOperation(boundLocal As BoundLocal) As ILocalReferenceExpression
+        Private Function CreateBoundLocalOperation(boundLocal As BoundLocal) As IOperation
+            If boundLocal.Syntax.Kind = SyntaxKind.IdentifierName AndAlso boundLocal.Syntax.Parent?.Kind = SyntaxKind.CatchStatement Then
+                Return OperationFactory.CreateVariableDeclaration(boundLocal.LocalSymbol, initialValue:=Nothing, semanticModel:=_semanticModel, syntax:=boundLocal.Syntax)
+            End If
+
             Dim local As ILocalSymbol = boundLocal.LocalSymbol
             Dim isDeclaration As Boolean = False
             Dim syntax As SyntaxNode = boundLocal.Syntax
@@ -1077,15 +1081,16 @@ Namespace Microsoft.CodeAnalysis.Semantics
         End Function
 
         Private Function CreateBoundCatchBlockOperation(boundCatchBlock As BoundCatchBlock) As ICatchClause
-            Dim handler As Lazy(Of IBlockStatement) = New Lazy(Of IBlockStatement)(Function() DirectCast(Create(boundCatchBlock.Body), IBlockStatement))
-            Dim caughtType As ITypeSymbol = boundCatchBlock.ExceptionSourceOpt?.Type
+            Dim exceptionDeclarationOrExpression As Lazy(Of IOperation) = New Lazy(Of IOperation)(
+                Function() If(boundCatchBlock.ExceptionSourceOpt IsNot Nothing, Create(boundCatchBlock.ExceptionSourceOpt), Nothing))
+            Dim exceptionType As ITypeSymbol = If(boundCatchBlock.ExceptionSourceOpt?.Type, DirectCast(_semanticModel.Compilation, VisualBasicCompilation).GetWellKnownType(WellKnownType.System_Exception))
             Dim filter As Lazy(Of IOperation) = New Lazy(Of IOperation)(Function() Create(boundCatchBlock.ExceptionFilterOpt))
-            Dim exceptionLocal As ILocalSymbol = boundCatchBlock.LocalOpt
+            Dim handler As Lazy(Of IBlockStatement) = New Lazy(Of IBlockStatement)(Function() DirectCast(Create(boundCatchBlock.Body), IBlockStatement))
             Dim syntax As SyntaxNode = boundCatchBlock.Syntax
             Dim type As ITypeSymbol = Nothing
             Dim constantValue As [Optional](Of Object) = New [Optional](Of Object)()
             Dim isImplicit As Boolean = boundCatchBlock.WasCompilerGenerated
-            Return New LazyCatchClause(handler, caughtType, filter, exceptionLocal, _semanticModel, syntax, type, constantValue, isImplicit)
+            Return New LazyCatchClause(exceptionDeclarationOrExpression, exceptionType, filter, handler, _semanticModel, syntax, type, constantValue, isImplicit)
         End Function
 
         Private Function CreateBoundBlockOperation(boundBlock As BoundBlock) As IBlockStatement
@@ -1095,7 +1100,7 @@ Namespace Microsoft.CodeAnalysis.Semantics
                     ' https://github.com/dotnet/roslyn/issues/21776
                     Return boundBlock.Statements.Select(Function(n) (s:=Create(n), bound:=n)).Where(
                         Function(tuple)
-                            Return tuple.s.Kind <> OperationKind.None OrElse tuple.bound.Kind = BoundKind.TryStatement OrElse
+                            Return tuple.s.Kind <> OperationKind.None OrElse
                                 tuple.bound.Kind = BoundKind.WithStatement OrElse tuple.bound.Kind = BoundKind.StopStatement OrElse
                                 tuple.bound.Kind = BoundKind.EndStatement
                         End Function).Select(Function(tuple) tuple.s).ToImmutableArray()

src/Compilers/VisualBasic/Test/Semantic/IOperation/IOperationTests.vb

-' Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
+' Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
 Imports Microsoft.CodeAnalysis.Semantics
 Imports Microsoft.CodeAnalysis.Test.Utilities
@@ -624,7 +624,10 @@ Module Program
 End Module]]>.Value
 
             Dim expectedOperationTree = <![CDATA[
-ICatchClause (Exception type: System.Exception, Exception local: ex As System.Exception) (OperationKind.None) (Syntax: 'Catch ex As ...  Is Nothing')
+ICatchClause (Exception type: System.Exception) (OperationKind.CatchClause) (Syntax: 'Catch ex As ...  Is Nothing')
+  ExceptionDeclarationOrExpression: IVariableDeclaration (1 variables) (OperationKind.VariableDeclaration) (Syntax: 'ex')
+      Variables: Local_1: ex As System.Exception
+      Initializer: null
   Filter: IBinaryOperatorExpression (BinaryOperatorKind.Equals) (OperationKind.BinaryOperatorExpression, Type: System.Boolean) (Syntax: 'ex Is Nothing')
       Left: IConversionExpression (Implicit, TryCast: False, Unchecked) (OperationKind.ConversionExpression, Type: System.Object) (Syntax: 'ex')
           Conversion: CommonConversion (Exists: True, IsIdentity: False, IsNumeric: False, IsReference: True, IsUserDefined: False) (MethodSymbol: null)

src/Compilers/VisualBasic/Test/Semantic/IOperation/IOperationTests_IWhileUntilLoopStatement.vb

-' Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
+' Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
 Imports Microsoft.CodeAnalysis.Semantics
 Imports Microsoft.CodeAnalysis.Test.Utilities
@@ -927,7 +927,7 @@ IWhileLoopStatement (LoopKind.While) (OperationKind.LoopStatement, IsInvalid) (S
                     Right: ILiteralExpression (OperationKind.LiteralExpression, Type: System.Int32, Constant: 1) (Syntax: '1')
           Right: ILiteralExpression (OperationKind.LiteralExpression, Type: System.Int32, Constant: 0) (Syntax: '0')
   Body: IBlockStatement (1 statements) (OperationKind.BlockStatement, IsInvalid) (Syntax: 'While Syste ... End While')
-      ITryStatement (OperationKind.None) (Syntax: 'Try ... End Try')
+      ITryStatement (OperationKind.TryStatement) (Syntax: 'Try ... End Try')
         Body: IBlockStatement (1 statements) (OperationKind.BlockStatement) (Syntax: 'Try ... End Try')
             IExpressionStatement (OperationKind.ExpressionStatement) (Syntax: 'y = CSByte(x / 2)')
               Expression: ISimpleAssignmentExpression (OperationKind.SimpleAssignmentExpression, Type: System.SByte) (Syntax: 'y = CSByte(x / 2)')

src/Test/Utilities/Portable/Compilation/OperationTreeVerifier.cs

@@ -557,7 +557,7 @@ public override void VisitLockStatement(ILockStatement operation)
             Visit(operation.Body, "Body");
         }
 
-        internal override void VisitTryStatement(ITryStatement operation)
+        public override void VisitTryStatement(ITryStatement operation)
         {
             LogString(nameof(ITryStatement));
             LogCommonPropertiesAndNewLine(operation);
@@ -567,12 +567,13 @@ internal override void VisitTryStatement(ITryStatement operation)
             Visit(operation.FinallyHandler, "Finally");
         }
 
-        internal override void VisitCatchClause(ICatchClause operation)
+        public override void VisitCatchClause(ICatchClause operation)
         {
             LogString(nameof(ICatchClause));
-            LogString($" (Exception type: {operation.CaughtType?.ToTestDisplayString()}, Exception local: {operation.ExceptionLocal?.ToTestDisplayString()})");
+            LogString($" (Exception type: {operation.ExceptionType?.ToTestDisplayString()})");
             LogCommonPropertiesAndNewLine(operation);
 
+            Visit(operation.ExceptionDeclarationOrExpression, "ExceptionDeclarationOrExpression");
             Visit(operation.Filter, "Filter");
             Visit(operation.Handler, "Handler");
         }

src/Test/Utilities/Portable/Compilation/TestOperationWalker.cs

@@ -180,15 +180,14 @@ public override void VisitLockStatement(ILockStatement operation)
             base.VisitLockStatement(operation);
         }
 
-        internal override void VisitTryStatement(ITryStatement operation)
+        public override void VisitTryStatement(ITryStatement operation)
         {
             base.VisitTryStatement(operation);
         }
 
-        internal override void VisitCatchClause(ICatchClause operation)
+        public override void VisitCatchClause(ICatchClause operation)
         {
-            var caughtType = operation.CaughtType;
-            var exceptionLocal = operation.ExceptionLocal;
+            var exceptionType = operation.ExceptionType;
 
             base.VisitCatchClause(operation);
         }