36public static NullableFlowState GetNullableState(ArrayBuilder<TypeWithState> types) 38NullableFlowState result = NullableFlowState.NotNull;

145public VisitResult(TypeSymbol? type, NullableAnnotation annotation, NullableFlowState state) 235private static readonly TypeWithState _invalidType = TypeWithState.Create(new UnsupportedMetadataTypeSymbol(), NullableFlowState.NotNull); 838var memberState = GetState(ref state, slot); 839var badState = symbolType.Type.IsPossiblyNullableReferenceTypeTypeParameter() && (annotations & FlowAnalysisAnnotations.NotNull) == 0 840? NullableFlowState.MaybeDefault 841: NullableFlowState.MaybeNull; 897SetState(ref this.State, memberSlot, type.Type.IsPossiblyNullableReferenceTypeTypeParameter() ? NullableFlowState.MaybeDefault : NullableFlowState.MaybeNull); 1192var parameterState = GetState(ref state, memberSlot); 1224SetState(ref this.State, memberSlot, NullableFlowState.MaybeNull); 1337var parameterState = GetState(ref state, slot); 1393var parameterState = GetState(ref stateWhen, slot); 1420private void EnforceNotNullIfNotNull(SyntaxNode? syntaxOpt, LocalState state, ImmutableArray<ParameterSymbol> parameters, ImmutableHashSet<string> inputParamNames, NullableFlowState outputState, ParameterSymbol? outputParam) 2008private NullableFlowState GetState(ref LocalState state, int slot) 2011return NullableFlowState.NotNull; 2017private void SetState(ref LocalState state, int slot, NullableFlowState value, bool useNotNullsAsDefault = false) 2039private NullableFlowState GetDefaultState(ref LocalState state, int slot) 2044return NullableFlowState.NotNull; 2073var result = NullableFlowState.NotNull; 2092return NullableFlowState.NotNull; 2421private static bool ShouldReportNullableAssignment(TypeWithAnnotations type, NullableFlowState state) 2438case NullableFlowState.NotNull: 2440case NullableFlowState.MaybeNull: 2516valueType.State == NullableFlowState.MaybeDefault; 2698var newState = valueType.State; 2802NullableFlowState value = isDefaultValue ? NullableFlowState.MaybeNull : fieldOrPropertyType.ToTypeWithState().State; 2814NullableFlowState.NotNull; 2862/// and the new state is not <see cref="NullableFlowState.NotNull"/>, this method should be called to perform the 2866private void SetStateAndTrackForFinally(ref LocalState state, int slot, NullableFlowState newState) 2870if (newState != NullableFlowState.NotNull && NonMonotonicState.HasValue) 2955private NullableFlowState GetDefaultState(Symbol symbol) 3048var state = GetParameterState(parameterType, parameter.FlowAnalysisAnnotations).State; 3086return TypeWithState.Create(parameterType.Type, NullableFlowState.MaybeDefault); 3091return TypeWithState.Create(parameterType.Type, NullableFlowState.NotNull); 3394SetState(ref state, slot, NullableFlowState.NotNull); 3667placeholderResult = new VisitResult(placeholder.Type, NullableAnnotation.NotAnnotated, NullableFlowState.NotNull); 3918SetResultType(node, TypeWithState.Create(null, NullableFlowState.NotNull)); 3926SetResultType(node, TypeWithState.Create(null, NullableFlowState.NotNull)); 4022NullableFlowState.NotNull)); 4204NullableFlowState resultState = getResultState(node, collectionKind); 4220static NullableFlowState getResultState(BoundCollectionExpression node, CollectionExpressionTypeKind collectionKind) 4232return NullableFlowState.NotNull; 4302(int slot, NullableFlowState resultState, Func<TypeSymbol, MethodSymbol?, int>? initialStateInferenceCompletion) = 4322NullableFlowState resultState, 4351NullableFlowState resultState) 4353Debug.Assert(resultState == NullableFlowState.NotNull); 4385(int slot, NullableFlowState resultState, Func<TypeSymbol, MethodSymbol?, int>? completion) inferInitialObjectState( 4393return (-1, NullableFlowState.NotNull, inferInitialObjectStateAsContinuation(node, arguments, argumentResults, hasObjectInitializer)); 4399var resultState = NullableFlowState.NotNull; 4431resultState = NullableFlowState.MaybeNull; 4488Debug.Assert(resultState == NullableFlowState.NotNull); 4497NullableFlowState operandState; 4668var result = new VisitResult(objectInitializer.Type, NullableAnnotation.NotAnnotated, NullableFlowState.NotNull); 4896SetAnalyzedNullability(node.ImplicitReceiverOpt, new VisitResult(node.ImplicitReceiverOpt.Type, NullableAnnotation.NotAnnotated, NullableFlowState.NotNull)); 4954SetResultType(node, TypeWithState.Create(node.Type, NullableFlowState.NotNull)); 4959var resultType = TypeWithState.Create(node.Type, NullableFlowState.NotNull); 5067SetResultType(node, TypeWithState.Create(anonymousType, NullableFlowState.NotNull)); 5099SetResultType(node, TypeWithState.Create(node.Type, NullableFlowState.NotNull)); 5104SetResultType(node, TypeWithState.Create(arrayType, NullableFlowState.NotNull)); 5180var elementState = BestTypeInferrer.GetNullableState(expressionTypes); 5382NullableFlowState resultState = NullableFlowState.NotNull; 5410resultState = NullableFlowState.MaybeNull; // Delegate removal can produce null. 5413resultState = NullableFlowState.NotNull; 6002SetState(ref stateToUpdate, slot, NullableFlowState.NotNull); 6031SetState(ref state, slot, NullableFlowState.NotNull); 6056if (GetState(ref state, slot) == NullableFlowState.NotNull) 6059SetState(ref state, slot, NullableFlowState.MaybeNull); 6088SetState(ref state, childSlot, NullableFlowState.NotNull); 6167SetState(ref this.State, leftSlot, NullableFlowState.NotNull); 6222BoundNullCoalescingOperatorResultKind.NoCommonType => (node.Type, NullableFlowState.NotNull), 6227BoundNullCoalescingOperatorResultKind.RightDynamicType => (rightResultType!, NullableFlowState.NotNull), 6234(TypeSymbol ResultType, NullableFlowState LeftState) getLeftResultType(TypeSymbol leftType, TypeSymbol rightType) 6245return (rightType, NullableFlowState.NotNull); 6251return (leftType, NullableFlowState.NotNull); 6254(TypeSymbol ResultType, NullableFlowState LeftState) getResultStateWithRightType(TypeSymbol leftType, TypeSymbol rightType) 6266TypeWithState.Create(leftType, NullableFlowState.NotNull), 6277return (rightType, NullableFlowState.NotNull); 6450SetResultType(node, TypeWithState.Create(resultType, NullableFlowState.MaybeDefault)); 6505var rValueState = consequenceRValue.State.Join(alternativeRValue.State); 6613NullableFlowState resultState; 6773SetResultType(node, TypeWithState.Create(rvalueType, NullableFlowState.NotNull)); 7290private NullableFlowState LearnFromCompareExchangeMethod(in CompareExchangeInfo compareExchangeInfo) 7310return NullableFlowState.NotNull; 7320var valueFlowState = compareExchangeInfo.Results[valueIndex].RValueType.State; 7327var locationFlowState = compareExchangeInfo.Results[locationIndex].RValueType.State; 7444return TypeWithState.Create(typeWithState.Type, NullableFlowState.NotNull); 7449return TypeWithState.Create(typeWithState.Type, NullableFlowState.MaybeDefault); 8058SetState(ref state, memberSlot, NullableFlowState.NotNull); 8360var adjustedState = LearnFromCompareExchangeMethod(in compareExchangeInfoOpt); 8503return TypeWithState.Create(typeWithState.Type, NullableFlowState.MaybeDefault); 8509return TypeWithState.Create(typeWithState.Type, NullableFlowState.NotNull); 8524return TypeWithState.Create(typeWithState.Type, NullableFlowState.MaybeDefault); 8528return TypeWithState.Create(typeWithState.Type, NullableFlowState.NotNull); 8543return TypeWithState.Create(typeWithState.Type, NullableFlowState.MaybeDefault); 8547return TypeWithState.Create(typeWithState.Type, NullableFlowState.NotNull); 9116NullableFlowState state = GetState(ref this.State, slot); 9391SetResultType(node, TypeWithState.Create(null, NullableFlowState.NotNull)); 9398SetState(ref this.State, slot, NullableFlowState.NotNull); 9416SetResultType(node, TypeWithState.Create(tupleOpt, NullableFlowState.NotNull)); 9539SetState(ref this.State, targetFieldSlot, NullableFlowState.NotNull); 9556SetState(ref this.State, targetFieldSlot, NullableFlowState.NotNull); 9851NullableFlowState resultState = NullableFlowState.NotNull; 9883resultState = NullableFlowState.NotNull; 9908return TypeWithState.Create(targetType, NullableFlowState.NotNull); 9914resultState = NullableFlowState.NotNull; 9918resultState = NullableFlowState.NotNull; 9923resultState = NullableFlowState.NotNull; 9983resultState = NullableFlowState.NotNull; 10145resultState = NullableFlowState.NotNull; 10214static TypeWithState calculateResultType(TypeWithAnnotations targetTypeWithNullability, bool fromExplicitCast, NullableFlowState resultState, bool isSuppressed, TypeSymbol targetType) 10218resultState = NullableFlowState.NotNull; 10223resultState = targetType?.IsTypeParameterDisallowingAnnotationInCSharp8() == true ? NullableFlowState.MaybeDefault : NullableFlowState.MaybeNull; 10230static NullableFlowState getReferenceConversionResultState(TypeWithAnnotations targetType, TypeWithState operandType) 10232var state = operandType.State; 10235case NullableFlowState.MaybeNull: 10241return NullableFlowState.MaybeDefault; 10247return (annotation == NullableAnnotation.Annotated) ? NullableFlowState.MaybeDefault : NullableFlowState.MaybeNull; 10251case NullableFlowState.MaybeDefault: 10254return NullableFlowState.MaybeNull; 10264static NullableFlowState getBoxingConversionResultState(TypeWithAnnotations targetType, TypeWithState operandType) 10266var state = operandType.State; 10267if (state == NullableFlowState.MaybeNull) 10272return NullableFlowState.MaybeDefault; 10282return (annotation == NullableAnnotation.Annotated) ? NullableFlowState.MaybeDefault : NullableFlowState.MaybeNull; 10292static NullableFlowState getUnboxingConversionResultState(TypeWithState operandType) 10294var state = operandType.State; 10295if (state == NullableFlowState.MaybeNull) 10297return NullableFlowState.MaybeDefault; 10302static NullableFlowState getConversionResultState(TypeWithState operandType) 10304var state = operandType.State; 10305if (state == NullableFlowState.MaybeNull) 10307return NullableFlowState.MaybeDefault; 10442var resultType = TypeWithState.Create(targetType, NullableFlowState.NotNull); 10485NullableFlowState operandState = operandType.State; 10550private TypeWithState GetConversionReturnTypeWithState(MethodSymbol method, bool isLiftedConversion, NullableFlowState operandState) 10594var resultType = TypeWithState.Create(targetTypeWithNullability.Type, NullableFlowState.NotNull); 10681unionTypeWithState = TypeWithState.Create(toType, NullableFlowState.NotNull); 10775private TypeWithState GetLiftedReturnType(TypeWithAnnotations returnType, NullableFlowState operandState) 10779NullableFlowState state = returnType.ToTypeWithState().State.Join(operandState); 10796private TypeWithState GetLiftedReturnTypeIfNecessary(bool isLifted, TypeWithAnnotations returnType, NullableFlowState operandState) 10892var result = TypeWithState.Create(delegateType, NullableFlowState.NotNull); 11189var rvalueResult = TypeWithState.Create(node.Type, NullableFlowState.NotNull); 11608var valueBeforeNullableWrapping = TypeWithState.Create(underlyingType.Type, NullableFlowState.NotNull); 11741SetResultType(node, TypeWithState.Create(receiverType.Type, NullableFlowState.NotNull)); 11765SetResultType(node, TypeWithState.Create(opType.Type, NullableFlowState.NotNull)); 11934SetResultType(node, TypeWithState.Create(receiverType.Type, NullableFlowState.NotNull)); 11962SetResultType(node, TypeWithState.Create(opType.Type, NullableFlowState.NotNull)); 12281var state = GetState(ref this.State, slot); 12303SetState(ref this.StateWhenTrue, slotToSet, NullableFlowState.NotNull); 12525if (enumeratorReturnType.State != NullableFlowState.NotNull) 12596var state = NullableFlowState.NotNull; 12800TypeWithState.Create(node.Type, node.OperatorKind.IsLifted() ? argumentResult.State : NullableFlowState.NotNull); 13066SetResultType(node, TypeWithState.Create(node.Type, NullableFlowState.NotNull)); 13088SetResultType(node, TypeWithState.Create(node.Type, NullableFlowState.MaybeDefault)); 13103SetState(ref this.State, slot, NullableFlowState.NotNull); 13149NullableFlowState resultState = NullableFlowState.NotNull; 13164resultState = NullableFlowState.MaybeDefault; 13202SetResultType(node, TypeWithState.Create(node.Type, node.Type?.CanContainNull() != false && node.ConstantValueOpt?.IsNull == true ? NullableFlowState.MaybeDefault : NullableFlowState.NotNull)); 13310node.IsAddition ? GetState(ref this.State, memberSlot).Meet(ResultType.State) : NullableFlowState.MaybeNull); 13427private bool ReportPossibleNullReceiverIfNeeded(TypeSymbol type, NullableFlowState state, bool checkNullableValueType, SyntaxNode syntax, out bool reportedDiagnostic) 13486SetResultType(node, TypeWithState.Create(node.Type, NullableFlowState.NotNull)); 13501SetResultType(node, TypeWithState.Create(node.Type, NullableFlowState.NotNull)); 13550SetResultType(node, TypeWithState.Create(node.Type, NullableFlowState.NotNull)); 13556SetResultType(node, TypeWithState.Create(type, NullableFlowState.NotNull)); 13624SetState(ref this.State, slot, NullableFlowState.NotNull); 13766Debug.Assert(ResultType is TypeWithState { Type: FunctionPointerTypeSymbol { }, State: NullableFlowState.NotNull }); 14072SetValue(Id, index, useNotNullsAsDefault ? NullableFlowState.NotNull : walker.GetDefaultState(ref this, slot)); 14076public NullableFlowState this[int slot] 14090private NullableFlowState GetValue(int id, int index) 14100private NullableFlowState GetValue(int index) 14104return NullableFlowState.NotNull; 14111var result = (_state[index], _state[index + 1]) switch 14113(false, false) => NullableFlowState.NotNull, // Should not be reachable 14114(true, false) => NullableFlowState.MaybeNull, 14115(false, true) => NullableFlowState.MaybeDefault, 14116(true, true) => NullableFlowState.NotNull 14122private void SetValue(int id, int index, NullableFlowState value) 14135private void SetValue(int index, NullableFlowState value) 14143NullableFlowState.MaybeNull => (true, false), 14144NullableFlowState.MaybeDefault => (false, true), 14145NullableFlowState.NotNull => (true, true), 14199var oldValue = oldReachable ? GetValue(i) : NullableFlowState.NotNull; 14200var newValue = oldValue.Join(other.GetValue(i)); 14225var oldValue = GetValue(i); 14226var newValue = oldValue.Meet(other.GetValue(i)); 14242var mayBeNull = GetValue(i) is NullableFlowState.MaybeNull or NullableFlowState.MaybeDefault; 14273NullableFlowState.MaybeNull => "?", 14274NullableFlowState.MaybeDefault => "??",

464SetState(ref State, outputSlot, NullableFlowState.NotNull); 516SetState(ref this.State, outputSlot, NullableFlowState.NotNull); // Slice value is assumed to be never null 524var inputState = GetState(ref this.State, inputSlot); 629var tempState = GetState(ref this.State, tempSlot); 1058NullableFlowState inferredState; 1108NullableFlowState inferredState = BestTypeInferrer.GetNullableState(resultTypes);

1226static NullableFlowState getTypeArgumentState(in TypeWithAnnotations typeWithAnnotations) 1231return NullableFlowState.NotNull; 1235return type.IsNullableTypeOrTypeParameter() ? NullableFlowState.MaybeNull : NullableFlowState.NotNull; 1240return type.IsTypeParameterDisallowingAnnotationInCSharp8() ? NullableFlowState.MaybeDefault : NullableFlowState.MaybeNull; 1242return NullableFlowState.NotNull; 1247return NullableFlowState.NotNull; 1249NullableFlowState? result = null; 1252var constraintState = getTypeArgumentState(constraintType); 1262return result ?? NullableFlowState.MaybeNull; 1265static bool constraintTypeAllows(in TypeWithAnnotations typeWithAnnotations, NullableFlowState state) 1267if (state == NullableFlowState.NotNull) 1294return state == NullableFlowState.MaybeNull;

104var flowState = TypeWithAnnotations.Create(type, annotation).ToTypeWithState().State;

11/// When in doubt we conservatively use <see cref="NullableFlowState.NotNull"/>

13public static bool MayBeNull(this NullableFlowState state) => state != NullableFlowState.NotNull; 15public static bool IsNotNull(this NullableFlowState state) => state == NullableFlowState.NotNull; 19/// The result is <see cref="NullableFlowState.MaybeNull"/> if either operand is that. 21public static NullableFlowState Join(this NullableFlowState a, NullableFlowState b) => (a > b) ? a : b; 25/// The result is <see cref="NullableFlowState.NotNull"/> if either operand is that. 27public static NullableFlowState Meet(this NullableFlowState a, NullableFlowState b) => (a < b) ? a : b; 29internal static CodeAnalysis.NullableFlowState ToPublicFlowState(this CSharp.NullableFlowState nullableFlowState) => 32CSharp.NullableFlowState.NotNull => CodeAnalysis.NullableFlowState.NotNull, 33CSharp.NullableFlowState.MaybeNull => CodeAnalysis.NullableFlowState.MaybeNull, 34CSharp.NullableFlowState.MaybeDefault => CodeAnalysis.NullableFlowState.MaybeNull, 39public static CSharp.NullableFlowState ToInternalFlowState(this CodeAnalysis.NullableFlowState flowState) => 42CodeAnalysis.NullableFlowState.None => CSharp.NullableFlowState.NotNull, 43CodeAnalysis.NullableFlowState.NotNull => CSharp.NullableFlowState.NotNull, 44CodeAnalysis.NullableFlowState.MaybeNull => CSharp.NullableFlowState.MaybeNull,

813static NullableFlowState getFlowState(TypeSymbol type, NullableAnnotation annotation) 817return annotation.IsAnnotated() ? NullableFlowState.MaybeDefault : NullableFlowState.NotNull; 821return annotation switch { NullableAnnotation.Annotated => NullableFlowState.MaybeDefault, NullableAnnotation.NotAnnotated => NullableFlowState.MaybeNull, _ => NullableFlowState.NotNull }; 825return annotation switch { NullableAnnotation.Annotated => NullableFlowState.MaybeDefault, _ => NullableFlowState.NotNull }; 829return NullableFlowState.MaybeNull; 831return annotation switch { NullableAnnotation.Annotated => NullableFlowState.MaybeNull, _ => NullableFlowState.NotNull };

17public readonly NullableFlowState State; 20public bool MayBeNull => State == NullableFlowState.MaybeNull; 21public bool IsNotNull => State == NullableFlowState.NotNull; 25return Create(type, NullableFlowState.MaybeDefault); 28public static TypeWithState Create(TypeSymbol? type, NullableFlowState defaultState) 30if (defaultState == NullableFlowState.MaybeDefault && 36var state = defaultState != NullableFlowState.NotNull && type?.CanContainNull() != false ? NullableFlowState.MaybeNull : NullableFlowState.NotNull; 45NullableFlowState state; 50state = NullableFlowState.MaybeDefault; 54state = NullableFlowState.NotNull; 63state = NullableFlowState.NotNull; 69private TypeWithState(TypeSymbol? type, NullableFlowState state) 71Debug.Assert(state == NullableFlowState.NotNull || type?.CanContainNull() != false); 72Debug.Assert(state != NullableFlowState.MaybeDefault || type is null || type.IsTypeParameterDisallowingAnnotationInCSharp8()); 81public TypeWithState WithNotNullState() => new TypeWithState(Type, NullableFlowState.NotNull); 83public TypeWithState WithSuppression(bool suppress) => suppress ? new TypeWithState(Type, NullableFlowState.NotNull) : this; 90return (State == NullableFlowState.MaybeDefault || asAnnotatedType) ? type.SetIsAnnotated(compilation) : type;