more nullability updates focus CS8619

ICSharpCode.BamlDecompiler/Baml/BamlContext.cs

@@ -37,7 +37,7 @@ namespace ICSharpCode.BamlDecompiler.Baml
 		public IDecompilerTypeSystem TypeSystem { get; }
 		public KnownThings KnownThings { get; }
 
-		Dictionary<ushort, (string FullAssemblyName, IModule Assembly)> assemblyMap = new Dictionary<ushort, (string FullAssemblyName, IModule Assembly)>();
+		Dictionary<ushort, (string? FullAssemblyName, IModule? Assembly)> assemblyMap = new Dictionary<ushort, (string? FullAssemblyName, IModule? Assembly)>();
 
 		public Dictionary<ushort, AssemblyInfoRecord> AssemblyIdMap { get; }
 		public Dictionary<ushort, AttributeInfoRecord> AttributeIdMap { get; }
@@ -88,7 +88,7 @@ namespace ICSharpCode.BamlDecompiler.Baml
 			return ctx;
 		}
 
-		public (string FullAssemblyName, IModule Assembly) ResolveAssembly(ushort id)
+		public (string? FullAssemblyName, IModule? Assembly) ResolveAssembly(ushort id)
 		{
 			id &= 0xfff;
 			if (!assemblyMap.TryGetValue(id, out var assembly))

ICSharpCode.Decompiler/CSharp/CallBuilder.cs

@@ -711,7 +711,7 @@ namespace ICSharpCode.Decompiler.CSharp
 				return false;
 			tokens = new List<(TokenKind Kind, int Index, int Alignment, string? Format)>();
 			int i = 0;
-			format = (string)crr.ConstantValue;
+			format = (string?)crr.ConstantValue;
 			foreach (var (kind, data) in TokenizeFormatString(format))
 			{
 				int index;
@@ -1827,7 +1827,7 @@ namespace ICSharpCode.Decompiler.CSharp
 		{
 			ExpressionBuilder expressionBuilder = this.expressionBuilder;
 			ExpressionWithResolveResult targetExpression;
-			(TranslatedExpression target, bool addTypeArguments, string methodName, ResolveResult result) = DisambiguateDelegateReference(method, invokeMethod, expectedTargetDetails, thisArg);
+			(TranslatedExpression target, bool addTypeArguments, string? methodName, ResolveResult result) = DisambiguateDelegateReference(method, invokeMethod, expectedTargetDetails, thisArg);
 			if (target.Expression != null)
 			{
 				var mre = new MemberReferenceExpression(target, methodName);

ICSharpCode.Decompiler/CSharp/Resolver/MemberLookup.cs

@@ -189,7 +189,7 @@ namespace ICSharpCode.Decompiler.CSharp.Resolver
 				{
 					var nestedTypes = type.GetNestedTypes(options: GetMemberOptions.IgnoreInheritedMembers | GetMemberOptions.ReturnMemberDefinitions);
 					// GetDefinition() might return null if some IType has a strange implementation of GetNestedTypes.
-					entities.AddRange(nestedTypes.Select(t => t.GetDefinition()).Where(td => td != null));
+					entities.AddRange(nestedTypes.Select(t => t.GetDefinition()).OfType<ITypeDefinition>());
 				}
 
 				foreach (var entityGroup in entities.GroupBy(e => e.Name))

ICSharpCode.Decompiler/CSharp/StatementBuilder.cs

@@ -152,7 +152,7 @@ namespace ICSharpCode.Decompiler.CSharp
 			return new IfElseStatement(condition, trueStatement, falseStatement).WithILInstruction(inst);
 		}
 
-		internal IEnumerable<ConstantResolveResult> CreateTypedCaseLabel(long i, IType type, List<(string Key, int Value)>? map = null)
+		internal IEnumerable<ConstantResolveResult> CreateTypedCaseLabel(long i, IType type, List<(string? Key, int Value)>? map = null)
 		{
 			object value;
 			// unpack nullable type, if necessary:
@@ -204,7 +204,7 @@ namespace ICSharpCode.Decompiler.CSharp
 			return TranslateSwitch(null, inst).WithILInstruction(inst);
 		}
 
-		SwitchStatement TranslateSwitch(BlockContainer switchContainer, SwitchInstruction inst)
+		SwitchStatement TranslateSwitch(BlockContainer? switchContainer, SwitchInstruction inst)
 		{
 			var oldBreakTarget = breakTarget;
 			breakTarget = switchContainer; // 'break' within a switch would only leave the switch
@@ -385,7 +385,7 @@ namespace ICSharpCode.Decompiler.CSharp
 		}
 
 		/// <summary>Target container that a 'break;' statement would break out of</summary>
-		BlockContainer breakTarget;
+		BlockContainer? breakTarget;
 		/// <summary>Dictionary from BlockContainer to label name for 'goto of_container';</summary>
 		readonly Dictionary<BlockContainer, string> endContainerLabels = new Dictionary<BlockContainer, string>();
 

ICSharpCode.Decompiler/CSharp/Syntax/Roles.cs

@@ -29,7 +29,7 @@ namespace ICSharpCode.Decompiler.CSharp.Syntax
 {
 	public static class Roles
 	{
-		public static readonly Role<AstNode> Root = AstNode.RootRole;
+		public static readonly Role<AstNode?> Root = AstNode.RootRole;
 
 		// some pre defined constants for common roles
 		public static readonly Role<Identifier> Identifier = new Role<Identifier>("Identifier", Syntax.Identifier.Null);

ICSharpCode.Decompiler/CSharp/Syntax/TypeSystemAstBuilder.cs

@@ -1291,7 +1291,7 @@ namespace ICSharpCode.Decompiler.CSharp.Syntax
 			}
 			return new CastExpression(ConvertType(type), new PrimitiveExpression(CSharpPrimitiveCast.Cast(enumBaseTypeCode, val, false)));
 
-			(long value, IField field) PrepareConstant(IField field)
+			(long value, IField? field) PrepareConstant(IField field)
 			{
 				if (!field.IsConst)
 					return (-1, null);

ICSharpCode.Decompiler/DebugInfo/IDebugInfoProvider.cs

@@ -20,8 +20,8 @@ namespace ICSharpCode.Decompiler.DebugInfo
 
 	public struct PdbExtraTypeInfo
 	{
-		public string[] TupleElementNames;
+		public string?[]? TupleElementNames;
-		public bool[] DynamicFlags;
+		public bool[]? DynamicFlags;
 	}
 
 	public interface IDebugInfoProvider

ICSharpCode.Decompiler/Disassembler/ReflectionDisassembler.cs

@@ -475,7 +475,7 @@ namespace ICSharpCode.Decompiler.Disassembler
 			}
 		}
 
-		class SecurityDeclarationDecoder : ICustomAttributeTypeProvider<(PrimitiveTypeCode, string)>
+		class SecurityDeclarationDecoder : ICustomAttributeTypeProvider<(PrimitiveTypeCode, string?)>
 		{
 			readonly ITextOutput output;
 			readonly IAssemblyResolver resolver;
@@ -488,32 +488,32 @@ namespace ICSharpCode.Decompiler.Disassembler
 				this.module = module;
 			}
 
-			public (PrimitiveTypeCode, string) GetPrimitiveType(PrimitiveTypeCode typeCode)
+			public (PrimitiveTypeCode, string?) GetPrimitiveType(PrimitiveTypeCode typeCode)
 			{
 				return (typeCode, null);
 			}
 
-			public (PrimitiveTypeCode, string) GetSystemType()
+			public (PrimitiveTypeCode, string?) GetSystemType()
 			{
 				return (0, "type");
 			}
 
-			public (PrimitiveTypeCode, string) GetSZArrayType((PrimitiveTypeCode, string) elementType)
+			public (PrimitiveTypeCode, string?) GetSZArrayType((PrimitiveTypeCode, string?) elementType)
 			{
 				return (elementType.Item1, (elementType.Item2 ?? PrimitiveTypeCodeToString(elementType.Item1)) + "[]");
 			}
 
-			public (PrimitiveTypeCode, string) GetTypeFromDefinition(MetadataReader reader, TypeDefinitionHandle handle, byte rawTypeKind)
+			public (PrimitiveTypeCode, string?) GetTypeFromDefinition(MetadataReader reader, TypeDefinitionHandle handle, byte rawTypeKind)
 			{
 				throw new NotImplementedException();
 			}
 
-			public (PrimitiveTypeCode, string) GetTypeFromReference(MetadataReader reader, TypeReferenceHandle handle, byte rawTypeKind)
+			public (PrimitiveTypeCode, string?) GetTypeFromReference(MetadataReader reader, TypeReferenceHandle handle, byte rawTypeKind)
 			{
 				throw new NotImplementedException();
 			}
 
-			public (PrimitiveTypeCode, string) GetTypeFromSerializedName(string name)
+			public (PrimitiveTypeCode, string?) GetTypeFromSerializedName(string name)
 			{
 				if (resolver == null)
 					throw new EnumUnderlyingTypeResolveException();
@@ -525,12 +525,12 @@ namespace ICSharpCode.Decompiler.Disassembler
 				return (0, name);
 			}
 
-			public PrimitiveTypeCode GetUnderlyingEnumType((PrimitiveTypeCode, string) type)
+			public PrimitiveTypeCode GetUnderlyingEnumType((PrimitiveTypeCode, string?) type)
 			{
 				return type.Item1;
 			}
 
-			public bool IsSystemType((PrimitiveTypeCode, string) type)
+			public bool IsSystemType((PrimitiveTypeCode, string?) type)
 			{
 				return "type" == type.Item2;
 			}

ICSharpCode.Decompiler/IL/ControlFlow/AwaitInCatchTransform.cs

@@ -420,7 +420,7 @@ namespace ICSharpCode.Decompiler.IL.ControlFlow
 		// =>
 		// throw(ldloc result.Handler.Variable)
 		internal static bool MatchExceptionCaptureBlock(ILTransformContext context, Block block,
-			ref ILVariable? objectVariable, out StLoc? typedExceptionVariableStore, out Block? captureBlock, out Block? throwBlock)
+			[NotNullWhen(true)] ref ILVariable? objectVariable, [NotNullWhen(true)] out StLoc? typedExceptionVariableStore, [NotNullWhen(true)] out Block? captureBlock, [NotNullWhen(true)] out Block? throwBlock)
 		{
 			bool DerivesFromException(IType t) => t.GetAllBaseTypes().Any(ty => ty.IsKnownType(KnownTypeCode.Exception));
 

ICSharpCode.Decompiler/IL/Transforms/SwitchOnStringTransform.cs

@@ -422,8 +422,8 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 				return false;
 			switchValueVar = switchValueVarCopy;
 			int conditionOffset = 1;
-			Block currentCaseBlock = isInternedBlock;
+			Block? currentCaseBlock = isInternedBlock;
-			var values = new List<(string, ILInstruction)>();
+			var values = new List<(string?, ILInstruction)>();
 
 			if (!switchValueVarCopy.IsSingleDefinition)
 				return false;
@@ -440,9 +440,9 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 					break;
 				if (!left.MatchLdLoc(switchValueVar))
 					break;
-				if (!right.MatchLdStr(out string value))
+				if (!right.MatchLdStr(out string? value))
 					break;
-				if (!(caseBlockJump.MatchBranch(out var caseBlock) || caseBlockJump.MatchLeave((BlockContainer)currentCaseBlock.Parent)))
+				if (!(caseBlockJump.MatchBranch(out var caseBlock) || caseBlockJump.MatchLeave((BlockContainer?)currentCaseBlock.Parent)))
 					break;
 				if (!currentCaseBlock.Instructions[conditionOffset + 1].MatchBranch(out currentCaseBlock))
 					break;
@@ -705,7 +705,7 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 			return true;
 		}
 
-		bool FixCasesWithoutValue(List<SwitchSection> sections, List<(string, int)> stringValues)
+		bool FixCasesWithoutValue(List<SwitchSection> sections, List<(string?, int)> stringValues)
 		{
 			bool HasLabel(SwitchSection section)
 			{

ICSharpCode.Decompiler/IL/Transforms/TransformExpressionTrees.cs

@@ -398,7 +398,7 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 						{
 							if (function.Kind == ILFunctionKind.ExpressionTree)
 							{
-								function.DelegateType = UnwrapExpressionTree(function.DelegateType);
+								function.DelegateType = UnwrapExpressionTree(function.DelegateType!);
 								function.Kind = ILFunctionKind.Delegate;
 							}
 							return function;
@@ -536,7 +536,7 @@ namespace ICSharpCode.Decompiler.IL.Transforms
 			}
 		}
 
-		(Func<ILVariable, ILInstruction>, IType) ConvertBind(CallInstruction invocation)
+		(Func<ILVariable, ILInstruction>?, IType) ConvertBind(CallInstruction invocation)
 		{
 			if (invocation.Arguments.Count != 2)
 				return (null, SpecialType.UnknownType);