private static bool CanIgnore(InvocationExpressionSyntax invocation, SemanticModel semanticModel, CancellationToken cancellationToken)
{
if (!(invocation.Parent is StatementSyntax))
{
return(true);
}
if (invocation.Parent is ExpressionStatementSyntax &&
invocation.Parent.Parent is BlockSyntax &&
semanticModel.GetSymbolSafe(invocation, cancellationToken) is IMethodSymbol method)
{
if (method.ReturnsVoid)
{
return(true);
}
if (method == KnownSymbol.StringBuilder.Append ||
method == KnownSymbol.StringBuilder.AppendLine ||
method == KnownSymbol.StringBuilder.AppendFormat ||
method == KnownSymbol.IList.Add ||
method == KnownSymbol.IList.Remove)
{
return(true);
}
if (method.TryGetSingleDeclaration(cancellationToken, out MethodDeclarationSyntax declaration))
{
using (var walker = ReturnValueWalker.Borrow(declaration, Search.Recursive, semanticModel, cancellationToken))
{
if (method.IsExtensionMethod)
{
var identifier = declaration.ParameterList.Parameters[0].Identifier;
foreach (var returnValue in walker)
{
if ((returnValue as IdentifierNameSyntax)?.Identifier.ValueText != identifier.ValueText)
{
return(false);
}
}
return(true);
}
foreach (var returnValue in walker)
{
if (!returnValue.IsKind(SyntaxKind.ThisExpression))
{
return(false);
}
}
return(true);
}
}
return(method.ReturnsVoid);
}
return(true);
}
private static bool CanIgnore(InvocationExpressionSyntax invocation, SemanticModel semanticModel, CancellationToken cancellationToken)
{
if (semanticModel.GetSymbolSafe(invocation, cancellationToken) is IMethodSymbol method)
{
if (method.ReturnsVoid ||
method.ReturnType == KnownSymbol.MoqIReturnsResult)
{
return(true);
}
if (ReferenceEquals(method.ContainingType, method.ReturnType) &&
method.ContainingType == KnownSymbol.StringBuilder)
{
return(true);
}
if ((method.Name == "Add" ||
method.Name == "Remove" ||
method.Name == "RemoveAll" ||
method.Name == "TryAdd" ||
method.Name == "TryRemove") &&
method.ReturnType.IsEither(KnownSymbol.Boolean, KnownSymbol.Int32, KnownSymbol.Int64))
{
return(true);
}
if (method.IsExtensionMethod)
{
method = method.ReducedFrom;
}
if (method.TrySingleDeclaration(cancellationToken, out MethodDeclarationSyntax declaration))
{
using (var walker = ReturnValueWalker.Borrow(declaration, Search.Recursive, semanticModel, cancellationToken))
{
foreach (var returnValue in walker)
{
if (returnValue is IdentifierNameSyntax identifierName &&
method.Parameters.TryFirst(x => x.Name == identifierName.Identifier.ValueText, out _))
{
return(true);
}
if (returnValue is InstanceExpressionSyntax)
{
return(true);
}
}
}
}
return(false);
}
return(true);
}
private static void Handle(SyntaxNodeAnalysisContext context)
{
if (context.IsExcludedFromAnalysis())
{
return;
}
if (context.Node is PropertyDeclarationSyntax propertyDeclaration &&
context.ContainingSymbol is IPropertySymbol property)
{
{
if (propertyDeclaration.ExpressionBody is ArrowExpressionClauseSyntax expressionBody)
{
if (property.Type.IsReferenceType &&
expressionBody.Expression is ObjectCreationExpressionSyntax)
{
context.ReportDiagnostic(Diagnostic.Create(GU0021CalculatedPropertyAllocates.Descriptor, expressionBody.GetLocation()));
}
else if (expressionBody.Expression is MemberAccessExpressionSyntax memberAccess &&
IsRelayReturn(memberAccess, context.SemanticModel, context.CancellationToken))
{
context.ReportDiagnostic(Diagnostic.Create(GU0008AvoidRelayProperties.Descriptor, memberAccess.GetLocation()));
}
}
else if (propertyDeclaration.TryGetGetter(out var getter))
{
using (var walker = ReturnValueWalker.Borrow(getter, Search.Recursive, context.SemanticModel, context.CancellationToken))
{
if (walker.TrySingle(out var returnValue))
{
if (property.Type.IsReferenceType &&
returnValue is ObjectCreationExpressionSyntax)
{
if (getter.Contains(returnValue) &&
returnValue.FirstAncestor <ReturnStatementSyntax>() is ReturnStatementSyntax returnStatement)
{
context.ReportDiagnostic(Diagnostic.Create(GU0021CalculatedPropertyAllocates.Descriptor, returnStatement.GetLocation()));
}
else
{
context.ReportDiagnostic(Diagnostic.Create(GU0021CalculatedPropertyAllocates.Descriptor, getter.GetLocation()));
}
}
else if (returnValue is MemberAccessExpressionSyntax memberAccess &&
IsRelayReturn(memberAccess, context.SemanticModel, context.CancellationToken))
{
if (getter.Contains(returnValue) &&
returnValue.FirstAncestor <ReturnStatementSyntax>() is ReturnStatementSyntax returnStatement)
{
context.ReportDiagnostic(Diagnostic.Create(GU0008AvoidRelayProperties.Descriptor, returnStatement.GetLocation()));
}
else
{
context.ReportDiagnostic(Diagnostic.Create(GU0008AvoidRelayProperties.Descriptor, getter.GetLocation()));
}
}
}
}
}
}
}
}
