private static void HandleAssignment(SyntaxNodeAnalysisContext context)
{
if (context.IsExcludedFromAnalysis())
{
return;
}
var assignment = (AssignmentExpressionSyntax)context.Node;
if (Disposable.IsCreation(assignment.Right, context.SemanticModel, context.CancellationToken)
.IsEither(Result.No, Result.Unknown))
{
return;
}
if (Disposable.IsAssignedWithCreated(assignment.Left, context.SemanticModel, context.CancellationToken, out ISymbol assignedSymbol)
.IsEither(Result.No, Result.Unknown))
{
return;
}
if (assignedSymbol == KnownSymbol.SerialDisposable.Disposable)
{
return;
}
if (IsDisposedBefore(assignedSymbol, assignment, context.SemanticModel, context.CancellationToken))
{
return;
}
context.ReportDiagnostic(Diagnostic.Create(Descriptor, assignment.GetLocation()));
}
private static void Handle(SyntaxNodeAnalysisContext context)
{
if (!context.IsExcludedFromAnalysis() &&
context.Node is ArgumentSyntax {
Parent : ArgumentListSyntax {
Parent : InvocationExpressionSyntax invocation
}
} argument&&
argument.RefOrOutKeyword.IsEither(SyntaxKind.RefKeyword, SyntaxKind.OutKeyword) &&
IsCreation(argument, context.SemanticModel, context.CancellationToken) &&
context.SemanticModel.TryGetSymbol(argument.Expression, context.CancellationToken, out var symbol))
{
if (symbol.Kind == SymbolKind.Discard ||
(LocalOrParameter.TryCreate(symbol, out var localOrParameter) &&
Disposable.ShouldDispose(localOrParameter, context.SemanticModel, context.CancellationToken)))
{
context.ReportDiagnostic(Diagnostic.Create(Descriptors.IDISP001DisposeCreated, argument.GetLocation()));
}
if (Disposable.IsAssignedWithCreated(symbol, invocation, context.SemanticModel, context.CancellationToken).IsEither(Result.Yes, Result.AssumeYes) &&
!Disposable.IsDisposedBefore(symbol, invocation, context.SemanticModel, context.CancellationToken))
{
context.ReportDiagnostic(Diagnostic.Create(Descriptors.IDISP003DisposeBeforeReassigning, argument.GetLocation()));
}
}
}
private static void HandleField(SyntaxNodeAnalysisContext context)
{
if (context.IsExcludedFromAnalysis())
{
return;
}
var field = (IFieldSymbol)context.ContainingSymbol;
if (field.IsStatic || field.IsConst)
{
return;
}
if (field.DeclaredAccessibility != Accessibility.Private &&
!field.IsReadOnly)
{
if (Disposable.IsAssignedWithCreated(field, context.SemanticModel, context.CancellationToken).IsEither(Result.Yes, Result.Maybe))
{
context.ReportDiagnostic(Diagnostic.Create(Descriptor, context.Node.GetLocation()));
}
}
else if (Disposable.IsAssignedWithCreatedAndInjected(field, context.SemanticModel, context.CancellationToken))
{
context.ReportDiagnostic(Diagnostic.Create(Descriptor, context.Node.GetLocation()));
}
}
private static void Handle(SyntaxNodeAnalysisContext context)
{
if (!context.IsExcludedFromAnalysis() &&
context.Node is ArgumentSyntax argument &&
argument.Parent is ArgumentListSyntax argumentList &&
argumentList.Parent is InvocationExpressionSyntax invocation &&
argument.RefOrOutKeyword.IsEither(SyntaxKind.RefKeyword, SyntaxKind.OutKeyword) &&
context.SemanticModel.TryGetSymbol(invocation, context.CancellationToken, out var method) &&
method.TrySingleDeclaration(context.CancellationToken, out BaseMethodDeclarationSyntax declaration) &&
method.TryFindParameter(argument, out var parameter) &&
Disposable.IsPotentiallyAssignableFrom(parameter.Type, context.Compilation))
{
if (Disposable.IsCreation(argument, context.SemanticModel, context.CancellationToken).IsEither(Result.Yes, Result.AssumeYes) &&
!Disposable.IsAddedToFieldOrProperty(parameter, declaration, context.SemanticModel, context.CancellationToken) &&
context.SemanticModel.TryGetSymbol(argument.Expression, context.CancellationToken, out ISymbol symbol))
{
if (LocalOrParameter.TryCreate(symbol, out var localOrParameter) &&
Disposable.ShouldDispose(localOrParameter, argument.Expression, context.SemanticModel, context.CancellationToken))
{
context.ReportDiagnostic(Diagnostic.Create(IDISP001DisposeCreated.Descriptor, argument.GetLocation()));
}
if (Disposable.IsAssignedWithCreated(symbol, invocation, context.SemanticModel, context.CancellationToken).IsEither(Result.Yes, Result.AssumeYes) &&
!Disposable.IsDisposedBefore(symbol, invocation, context.SemanticModel, context.CancellationToken))
{
context.ReportDiagnostic(Diagnostic.Create(IDISP003DisposeBeforeReassigning.Descriptor, argument.GetLocation()));
}
}
}
}
private static void HandleArgument(SyntaxNodeAnalysisContext context)
{
if (context.IsExcludedFromAnalysis())
{
return;
}
var argument = (ArgumentSyntax)context.Node;
if (argument.RefOrOutKeyword.IsKind(SyntaxKind.None))
{
return;
}
var invocation = argument.FirstAncestor <InvocationExpressionSyntax>();
if (invocation == null)
{
return;
}
var method = context.SemanticModel.GetSymbolSafe(invocation, context.CancellationToken);
if (method == null ||
method.DeclaringSyntaxReferences.Length == 0)
{
return;
}
if (Disposable.IsCreation(argument, context.SemanticModel, context.CancellationToken)
.IsEither(Result.No, Result.Unknown))
{
return;
}
var symbol = context.SemanticModel.GetSymbolSafe(argument.Expression, context.CancellationToken);
if (Disposable.IsAssignedWithCreated(symbol, argument.FirstAncestor <InvocationExpressionSyntax>(), context.SemanticModel, context.CancellationToken)
.IsEither(Result.No, Result.Unknown))
{
return;
}
if (IsDisposedBefore(symbol, argument.Expression, context.SemanticModel, context.CancellationToken))
{
return;
}
context.ReportDiagnostic(Diagnostic.Create(Descriptor, argument.GetLocation()));
}
private static void HandleProperty(SyntaxNodeAnalysisContext context)
{
if (context.IsExcludedFromAnalysis())
{
return;
}
var property = (IPropertySymbol)context.ContainingSymbol;
if (property.IsStatic ||
property.IsIndexer)
{
return;
}
var propertyDeclaration = (PropertyDeclarationSyntax)context.Node;
if (propertyDeclaration.ExpressionBody != null)
{
return;
}
if (propertyDeclaration.TryGetSetAccessorDeclaration(out AccessorDeclarationSyntax setter) &&
setter.Body != null)
{
// Handle the backing field
return;
}
if (property.SetMethod != null &&
property.SetMethod.DeclaredAccessibility != Accessibility.Private)
{
if (Disposable.IsAssignedWithCreated(property, context.SemanticModel, context.CancellationToken)
.IsEither(Result.Yes, Result.Maybe))
{
context.ReportDiagnostic(Diagnostic.Create(Descriptor, context.Node.GetLocation()));
}
}
else if (Disposable.IsAssignedWithCreatedAndInjected(property, context.SemanticModel, context.CancellationToken))
{
context.ReportDiagnostic(Diagnostic.Create(Descriptor, context.Node.GetLocation()));
}
}
private static bool TryCreateDisposeStatement(AssignmentExpressionSyntax assignment, SemanticModel semanticModel, CancellationToken cancellationToken, out StatementSyntax result)
{
result = null;
if (!(assignment.Parent is StatementSyntax && assignment.Parent.Parent is BlockSyntax))
{
return(false);
}
if (Disposable.IsAssignedWithCreated(assignment.Left, semanticModel, cancellationToken, out var assignedSymbol)
.IsEither(Result.No, Result.Unknown))
{
return(false);
}
var prefix = (assignedSymbol is IPropertySymbol || assignedSymbol is IFieldSymbol) &&
!assignment.UsesUnderscore(semanticModel, cancellationToken)
? "this."
: string.Empty;
if (!Disposable.IsAssignableTo(MemberType(assignedSymbol)))
{
result = SyntaxFactory.ParseStatement($"({prefix}{assignment.Left} as System.IDisposable)?.Dispose();")
.WithLeadingTrivia(SyntaxFactory.ElasticMarker)
.WithTrailingTrivia(SyntaxFactory.ElasticMarker)
.WithSimplifiedNames();
return(true);
}
if (IsAlwaysAssigned(assignedSymbol))
{
result = SyntaxFactory.ParseStatement($"{prefix}{assignedSymbol.Name}.Dispose();")
.WithLeadingTrivia(SyntaxFactory.ElasticMarker)
.WithTrailingTrivia(SyntaxFactory.ElasticMarker);
return(true);
}
result = SyntaxFactory.ParseStatement($"{prefix}{assignedSymbol.Name}?.Dispose();")
.WithLeadingTrivia(SyntaxFactory.ElasticMarker)
.WithTrailingTrivia(SyntaxFactory.ElasticMarker);
return(true);
}
