WI #2306 Protect against NullReferenceException when reading NameLiteral property

TypeCobol.Test/Parser/Programs/Cobol85/RedefinesWithReplace.PGM.txt

@@ -0,0 +1,19 @@
+--- Diagnostics ---
+Line 10[34,40] <27, Error, Syntax> - Syntax error : mismatched input ':zoneA:' expecting user defined word RuleStack=codeElement>dataDescriptionEntry>redefinesClause>dataNameReference,  OffendingSymbol=[34,40::zoneA:]<PartialCobolWord>
+Line 10[8,41] <30, Error, Semantics> - Semantic error: Illegal REDEFINES: Target cannot be identified
+
+--- Program ---
+PROGRAM: TCOBCOMP common:False initial:False recursive:False
+ author: ? written: ? compiled: ? installation: ? security: ?
+--- Intrinsic:Namespace:Program:Global:Local
+-- DATA --------
+  zone1:Alphanumeric
+  zone1-redef:Alphanumeric
+  z-label:Alphanumeric
+  z-content:Alphanumeric
+--- Intrinsic
+-- TYPES -------
+  BOOL:BOOL
+  DATE:DATE
+  CURRENCY:CURRENCY
+  STRING:STRING

TypeCobol.Test/Parser/Programs/Cobol85/RedefinesWithReplace.rdz.cbl

@@ -0,0 +1,16 @@
+       IDENTIFICATION DIVISION.
+       PROGRAM-ID. TCOBCOMP.
+       DATA DIVISION.
+       WORKING-STORAGE SECTION.
+       REPLACE ==:zone:== BY ==zone1==.
+       01 :zone: PIC X(120).
+      * Undefined REDEFINES target, we get 2 diagnostics:
+      * - one for the invalid parsing of the Redefines entry
+      * - one for the invalid semantics of the REDEFINES
+       01 :zone:-redef REDEFINES :zoneA:.
+          05 z-label   PIC X(20).
+          05 z-content PIC X(100).
+       PROCEDURE DIVISION.
+           GOBACK
+           .
+       END PROGRAM TCOBCOMP.

TypeCobol/Compiler/CodeElements/Expressions/StorageArea.cs

@@ -1,8 +1,4 @@
-using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Threading;
-using JetBrains.Annotations;
+using JetBrains.Annotations;
 using TypeCobol.Compiler.Nodes;
 using TypeCobol.Compiler.Scanner;
 
@@ -536,7 +532,7 @@ public IntrinsicFunctionCall([CanBeNull] ExternalName intrinsicFunctionName, Cal
         [CanBeNull]
         public ExternalName IntrinsicFunctionName { get; private set; }
         public override string FunctionName { get { return IntrinsicFunctionName?.Name; } }
-        public override Token FunctionNameToken { get { return IntrinsicFunctionName?.NameLiteral.Token; } }
+        public override Token FunctionNameToken { get { return IntrinsicFunctionName?.NameLiteral?.Token; } }
 
         public override bool NeedDeclaration
         {
@@ -567,7 +563,7 @@ public UserDefinedFunctionCall([CanBeNull] SymbolReference functionName, CallSit
         [CanBeNull]
         public SymbolReference UserDefinedFunctionName { get; private set;  }
         public override string FunctionName { get { return UserDefinedFunctionName?.Name; } }
-        public override Token FunctionNameToken { get { return UserDefinedFunctionName?.NameLiteral.Token; } }
+        public override Token FunctionNameToken { get { return UserDefinedFunctionName?.NameLiteral?.Token; } }
 
         public override string Namespace { get { return (UserDefinedFunctionName as QualifiedSymbolReference) == null ? null : ((QualifiedSymbolReference)UserDefinedFunctionName).Tail.Name; } }
 
@@ -592,7 +588,7 @@ public ProcedureCall(SymbolReference name, List<CallSiteParameter> inputs, List<
 
         public SymbolReference ProcedureName { get; private set; }
         public override string FunctionName { get { return ProcedureName.Name; } }
-        public override Token FunctionNameToken { get { return ProcedureName.NameLiteral.Token; } }
+        public override Token FunctionNameToken { get { return ProcedureName.NameLiteral?.Token; } }
 
         public List<CallSiteParameter> InputParameters { get; private set; }
         public List<CallSiteParameter> InoutParameters { get; private set; }

TypeCobol/Compiler/CodeModel/SymbolTable.cs

@@ -819,7 +819,7 @@ public IList<Paragraph> GetParagraph(SymbolReference symbolRef, Section sectionN
             {
                 //If paragraph is qualified we get a paragraph and a section name
                 var qualifiedSymbolReference = (QualifiedSymbolReference) symbolRef;
-                paragraphName = qualifiedSymbolReference.NameLiteral.Value;
+                paragraphName = qualifiedSymbolReference.Head.Name;
                 parentSectionName = qualifiedSymbolReference.Tail.Name;
             }
             else
@@ -830,7 +830,7 @@ public IList<Paragraph> GetParagraph(SymbolReference symbolRef, Section sectionN
             }
 
             //Retrieve all paragraphs with matching name, then apply additional filters
-            if (Paragraphs.TryGetValue(paragraphName, out var candidates))
+            if (paragraphName != null && Paragraphs.TryGetValue(paragraphName, out var candidates))
             {
                 if (parentSectionName != null)
                 {

TypeCobol/Compiler/Diagnostics/Cobol2002Checker.cs

@@ -1,12 +1,9 @@
-using System.Linq;
-using System.Collections.Generic;
-using TypeCobol.Compiler.AntlrUtils;
+using TypeCobol.Compiler.AntlrUtils;
 using TypeCobol.Compiler.CodeElements;
 using TypeCobol.Compiler.CodeElements.Expressions;
 using TypeCobol.Compiler.Parser;
 using TypeCobol.Compiler.Parser.Generated;
 using TypeCobol.Compiler.Nodes;
-using TypeCobol.Compiler.Scanner;
 
 namespace TypeCobol.Compiler.Diagnostics
 {
@@ -147,7 +144,9 @@ public static void OnNode(DataRedefines redefinesNode)
 
             if (redefinedVariable == null)
             {
-                string message = "Illegal REDEFINES: Symbol \'" + redefinesSymbolReference + "\' is not referenced";
+                var message = redefinesSymbolReference.Name != null
+                    ? "Illegal REDEFINES: Symbol \'" + redefinesSymbolReference + "\' is not referenced"
+                    : "Illegal REDEFINES: Target cannot be identified";
                 DiagnosticUtils.AddError(redefinesNode, message, redefinesSymbolReference, code: MessageCode.SemanticTCErrorInParser);
                 return;
             }

TypeCobol/Compiler/Diagnostics/CodeElementCheckers.cs

@@ -256,7 +256,7 @@ private static void CheckCallUsings(CallStatement statement)
         {
             foreach (var inputParameter in statement.InputParameters)
             {
-                var errorPosition = inputParameter.StorageAreaOrValue?.MainSymbolReference?.NameLiteral.Token;
+                var errorPosition = inputParameter.StorageAreaOrValue?.MainSymbolReference?.NameLiteral?.Token;
 
                 // TODO#249 these checks should be done during semantic phase, after symbol type resolution
                 // TODO#249 if input is a file name AND input.SendingMode.Value == SendingMode.ByContent OR ByValue
@@ -736,10 +736,16 @@ public static void OnCodeElement(RepositoryParagraph paragraph, CodeElementsPars
             {
                 foreach (var intrinsicFunction in intrinsicFunctions)
                 {
-                    Token token = intrinsicFunction.NameLiteral.Token;
                     var intrinsicFunctionName = intrinsicFunction.Name;
                     if (!CobolIntrinsicFunctions.IsAllowedInRepositoryParagraph(intrinsicFunctionName))
                     {
+                        /*
+                         * NameLiteral cannot be null here, otherwise intrinsicFuntionName would also be null
+                         * and IsAllowedInRepositoryParagraph would then have returned true.
+                         */
+                        System.Diagnostics.Debug.Assert(intrinsicFunction.NameLiteral != null);
+
+                        Token token = intrinsicFunction.NameLiteral.Token;
                         DiagnosticUtils.AddError(paragraph, $"\"{intrinsicFunctionName}\" was specified in the \"FUNCTION\" phrase of the \"REPOSITORY\" paragraph, but the keyword \"FUNCTION\" is always required for this function.", token);
                     }
                 }

TypeCobol/Compiler/Diagnostics/TypeCobolChecker.cs

@@ -618,10 +618,9 @@ public static void OnNode(FunctionDeclaration functionDeclaration)
             var functions = functionDeclaration.SymbolTable.GetFunction(headerNameURI, functionDeclaration.Profile);
             if (functions.Count > 1)
             {
-                Token nameToken = header.FunctionName.NameLiteral.Token;
                 DiagnosticUtils.AddError(functionDeclaration,
                     "A function \"" + headerNameURI.Head + "\" with the same profile already exists in namespace \"" +
-                    headerNameURI.Tail + "\".", nameToken, null, MessageCode.SemanticTCErrorInParser);
+                    headerNameURI.Tail + "\".", header.FunctionName, MessageCode.SemanticTCErrorInParser);
             }
         }
 

TypeCobol/Compiler/Parser/CodeElementBuilder/CobolExpressionsBuilder.cs

@@ -2,7 +2,6 @@
 using TypeCobol.Compiler.AntlrUtils;
 using TypeCobol.Compiler.CodeElements;
 using TypeCobol.Compiler.Parser.Generated;
-using System.Collections.Generic;
 using TypeCobol.Compiler.Diagnostics;
 using TypeCobol.Compiler.Scanner;
 
@@ -240,13 +239,21 @@ internal StorageArea CreateLinageCounterSpecialRegister(CodeElementsParser.Linag
             var specialRegister = new FilePropertySpecialRegister(
                 ParseTreeUtils.GetFirstToken(context.LINAGE_COUNTER()),
                 CobolWordsBuilder.CreateFileNameReference(context.fileNameReference()));
-            if(specialRegister.DataDescriptionEntry != null) {
-                var dataDescription = specialRegister.DataDescriptionEntry;
-                CobolWordsBuilder.symbolInformationForTokens[specialRegister.DataDescriptionEntry.DataName.NameLiteral.Token] = specialRegister.DataDescriptionEntry.DataName;
+
+            var dataName = specialRegister.DataDescriptionEntry?.DataName;
+            var dataNameToken = dataName?.NameLiteral?.Token;
+            if (dataNameToken != null)
+            {
+                CobolWordsBuilder.symbolInformationForTokens[dataNameToken] = dataName;
             }
-            if (specialRegister.SymbolReference != null) {
-                CobolWordsBuilder.symbolInformationForTokens[specialRegister.SymbolReference.NameLiteral.Token] = specialRegister.SymbolReference;
+
+            var specialRegisterReference = specialRegister.SymbolReference;
+            var specialRegisterReferenceToken = specialRegisterReference?.NameLiteral?.Token;
+            if (specialRegisterReferenceToken != null)
+            {
+                CobolWordsBuilder.symbolInformationForTokens[specialRegisterReferenceToken] = specialRegisterReference;
             }
+
             return specialRegister;
         }
 
@@ -255,14 +262,19 @@ internal StorageArea CreateAddressOfSpecialRegister(CodeElementsParser.AddressOf
             var specialRegister = new StorageAreaPropertySpecialRegister(
                 ParseTreeUtils.GetFirstToken(context.ADDRESS()),
                 CreateStorageAreaReference(context.storageAreaReference()));
-            if (specialRegister.DataDescriptionEntry != null)
+
+            var specialRegisterName = specialRegister.DataDescriptionEntry?.DataName;
+            var specialRegisterNameToken = specialRegisterName?.NameLiteral?.Token;
+            if (specialRegisterNameToken != null)
             {
-                var dataDescription = specialRegister.DataDescriptionEntry;
-                CobolWordsBuilder.symbolInformationForTokens[specialRegister.DataDescriptionEntry.DataName.NameLiteral.Token] = specialRegister.DataDescriptionEntry.DataName;
+                CobolWordsBuilder.symbolInformationForTokens[specialRegisterNameToken] = specialRegisterName;
             }
-            if (specialRegister.SymbolReference != null)
+
+            var specialRegisterReference = specialRegister.SymbolReference;
+            var specialRegisterReferenceToken = specialRegisterReference?.NameLiteral?.Token;
+            if (specialRegisterReferenceToken != null)
             {
-                CobolWordsBuilder.symbolInformationForTokens[specialRegister.SymbolReference.NameLiteral.Token] = specialRegister.SymbolReference;
+                CobolWordsBuilder.symbolInformationForTokens[specialRegisterReferenceToken] = specialRegisterReference;
             }
             return specialRegister;
         }
@@ -272,15 +284,21 @@ internal StorageArea CreateLengthOfSpecialRegister(CodeElementsParser.LengthOfSp
             var specialRegister = new StorageAreaPropertySpecialRegister(
                 ParseTreeUtils.GetFirstToken(context.LENGTH()),
                 CreateStorageAreaReference(context.storageAreaReference()));
-            if (specialRegister.DataDescriptionEntry != null)
+
+            var specialRegisterDataName = specialRegister.DataDescriptionEntry?.DataName;
+            var specialRegisterDataNameToken = specialRegisterDataName?.NameLiteral?.Token;
+            if (specialRegisterDataNameToken != null)
             {
-                var dataDescription = specialRegister.DataDescriptionEntry;
-                CobolWordsBuilder.symbolInformationForTokens[specialRegister.DataDescriptionEntry.DataName.NameLiteral.Token] = specialRegister.DataDescriptionEntry.DataName;
+                CobolWordsBuilder.symbolInformationForTokens[specialRegisterDataNameToken] = specialRegisterDataName;
             }
-            if (specialRegister.SymbolReference != null)
+
+            var specialRegisterReference = specialRegister.SymbolReference;
+            var specialRegisterReferenceToken = specialRegisterReference?.NameLiteral?.Token;
+            if (specialRegisterReferenceToken != null)
             {
-                CobolWordsBuilder.symbolInformationForTokens[specialRegister.SymbolReference.NameLiteral.Token] = specialRegister.SymbolReference;
+                CobolWordsBuilder.symbolInformationForTokens[specialRegisterReferenceToken] = specialRegisterReference;
             }
+
             return specialRegister;
         }
 
@@ -317,8 +335,12 @@ internal StorageArea CreateFunctionIdentifier(CodeElementsParser.FunctionIdentif
             if (functionCall.FunctionName != null && functionCall.FunctionNameToken != null)
             {
                 var functionCallResult = new FunctionCallResult(functionCall);
+                System.Diagnostics.Debug.Assert(functionCallResult.DataDescriptionEntry.DataName != null);
+                System.Diagnostics.Debug.Assert(functionCallResult.DataDescriptionEntry.DataName.NameLiteral.Token != null);
                 CobolWordsBuilder.symbolInformationForTokens[functionCallResult.DataDescriptionEntry.DataName.NameLiteral.Token] =
                     functionCallResult.DataDescriptionEntry.DataName;
+                System.Diagnostics.Debug.Assert(functionCallResult.SymbolReference != null);
+                System.Diagnostics.Debug.Assert(functionCallResult.SymbolReference.NameLiteral.Token != null);
                 CobolWordsBuilder.symbolInformationForTokens[functionCallResult.SymbolReference.NameLiteral.Token] =
                     functionCallResult.SymbolReference;
                 return functionCallResult;

TypeCobol/Compiler/Parser/CodeElementBuilder/CobolWordsBuilder.cs

@@ -67,6 +67,8 @@ internal CharacterValue CreateFigurativeConstant(CodeElementsParser.FigurativeCo
             if (context.symbolicCharacterReference() != null)
             {
                 var symbolicCharacterReference = CreateSymbolicCharacterReference(context.symbolicCharacterReference());
+                System.Diagnostics.Debug.Assert(symbolicCharacterReference.NameLiteral != null);
+                System.Diagnostics.Debug.Assert(symbolicCharacterReference.NameLiteral.Token != null);
                 return new CharacterValue(symbolicCharacterReference);
             }
 
@@ -172,6 +174,8 @@ private RepeatedCharacterValue CreateRepeatedCharacterValue([CanBeNull] Token al
             if (context.symbolicCharacterReference() != null)
             {
                 var symbolicCharacterReference = CreateSymbolicCharacterReference(context.symbolicCharacterReference());
+                System.Diagnostics.Debug.Assert(symbolicCharacterReference.NameLiteral != null);
+                System.Diagnostics.Debug.Assert(symbolicCharacterReference.NameLiteral.Token != null);
                 return new RepeatedCharacterValue(allToken, symbolicCharacterReference);
             }
 
@@ -803,7 +807,13 @@ internal SymbolReference CreateIndexNameReference(CodeElementsParser.QualifiedIn
 
             var reference = CreateQualifiedSymbolReference(new SymbolReference(headLiteral, SymbolType.IndexName), new SymbolReference(CreateAlphanumericValue(tail[0]), SymbolType.IndexName), false);
             for (int c = 1; c < tail.Length; c++) reference = CreateQualifiedSymbolReference(reference, new SymbolReference(CreateAlphanumericValue(tail[c]), SymbolType.IndexName), false);
-            symbolInformationForTokens[reference.NameLiteral.Token] = reference;
+
+            var token = reference.NameLiteral?.Token;
+            if (token != null)
+            {
+                symbolInformationForTokens[token] = reference;
+            }
+
             return reference;
         }
 
@@ -871,7 +881,12 @@ internal SymbolReference CreateQualifiedParagraphNameReference(CodeElementsParse
         private SymbolReference CreateQualifiedParagraphNameReference(CodeElementsParser.ParagraphNameReferenceContext head, CodeElementsParser.SectionNameReferenceContext tail, bool isCOBOL = true)
         {
             var reference = CreateQualifiedSymbolReference(CreateParagraphNameReference(head), CreateSectionNameReference(tail), isCOBOL);
-            symbolInformationForTokens[reference.NameLiteral.Token] = reference;
+            var token = reference.NameLiteral?.Token;
+            if (token != null)
+            {
+                symbolInformationForTokens[token] = reference;
+            }
+
             return reference;
         }
 
@@ -912,9 +927,11 @@ private SymbolReference CreateQualifiedDataName(CodeElementsParser.DataNameRefer
                 }
                 qname = CreateQualifiedSymbolReference(qname, current, isCOBOL);
             }
-            if (qname != null)
+
+            var token = qname?.NameLiteral?.Token;
+            if (token != null)
             {
-                symbolInformationForTokens[qname.NameLiteral.Token] = qname;
+                symbolInformationForTokens[token] = qname;
                 return qname;
             }
 
@@ -954,7 +971,13 @@ private SymbolReference CreateQualifiedConditionName(CodeElementsParser.Conditio
                     qname = CreateQualifiedSymbolReference(qname, part, isCOBOL);
                 }
             }
-            symbolInformationForTokens[qname.NameLiteral.Token] = qname;
+
+            var token = qname.NameLiteral?.Token;
+            if (token != null)
+            {
+                symbolInformationForTokens[token] = qname;
+            }
+
             return qname;
         }
 
@@ -1015,7 +1038,12 @@ private SymbolReference CreateQualifiedDataNameOrQualifiedConditionNameTCFunctio
         {
             var reference = CreateQualifiedSymbolReference(CreateDataNameReferenceOrConditionNameReferenceOrConditionForUPSISwitchNameReferenceOrTCFunctionProcedure(head), CreateDataNameReferenceOrFileNameReferenceOrMnemonicForUPSISwitchNameReference(tail[0]), isCOBOL);
             for (int c = 1; c < tail.Length; c++) reference = CreateQualifiedSymbolReference(reference, CreateDataNameReferenceOrFileNameReferenceOrMnemonicForUPSISwitchNameReference(tail[c]), isCOBOL);
-            symbolInformationForTokens[reference.NameLiteral.Token] = reference;
+            var token = reference.NameLiteral?.Token;
+            if (token != null)
+            {
+                symbolInformationForTokens[token] = reference;
+            }
+
             return reference;
         }
 
@@ -1134,7 +1162,12 @@ internal ExternalName CreateQualifiedTextName(CodeElementsParser.QualifiedTextNa
             {
                 ExternalName libraryName = CreateLibraryName(context.libraryName());
                 var qualifiedTextName = new QualifiedTextName(textName, libraryName);
-                symbolInformationForTokens[qualifiedTextName.NameLiteral.Token] = qualifiedTextName;
+                var textNameToken = qualifiedTextName.NameLiteral?.Token;
+                if (textNameToken != null)
+                {
+                    symbolInformationForTokens[textNameToken] = qualifiedTextName;
+                }
+
                 return qualifiedTextName;
             }
         }