public override void Visit(SyntaxNode node)
{
if (node is ExpressionSyntax)
{
var tinfo = context.SemanticModel.GetTypeInfo(node);
var tSrc = tinfo.Type as INamedTypeSymbol;
var tDst = tinfo.ConvertedType as INamedTypeSymbol;
if (tSrc != null && tDst != null &&
(object)tSrc.ConstructedFrom == cache.GetGenericTask(context.SemanticModel) &&
(object)tDst == cache.GetTask(context.SemanticModel))
{
context.ReportDiagnostic(Diagnostic.Create(ImplicitTaskTask, node.GetLocation()));
return;
}
}
base.Visit(node);
}
public void AnalyzeStatementExpression(WellKnownTypeCache cache, SyntaxNodeAnalysisContext context)
{
// If we encounter "await e;" where the result type of the await is a Task ...
var expression = (context.Node as ExpressionStatementSyntax).Expression;
if (expression == null)
{
return;
}
if (expression.Kind() != SyntaxKind.AwaitExpression)
{
return;
}
var typeInfo = context.SemanticModel.GetTypeInfo(expression);
var type = typeInfo.Type as INamedTypeSymbol;
if (type == null)
{
return;
}
if ((object)type != cache.GetTask(context.SemanticModel) && (object)type.ConstructedFrom != cache.GetGenericTask(context.SemanticModel))
{
return;
}
// and if "e" didn't have the form "Task.WhenAny(...)" ...
var awaitOperand = (expression as AwaitExpressionSyntax).Expression;
if (awaitOperand.Kind() == SyntaxKind.InvocationExpression)
{
var targetNode = (awaitOperand as InvocationExpressionSyntax).Expression;
if (targetNode != null)
{
var targetSymbol = context.SemanticModel.GetSymbolInfo(targetNode).Symbol;
if (targetSymbol != null)
{
if ((object)targetSymbol.ContainingType == cache.GetTask(context.SemanticModel) && targetSymbol.Name == "WhenAny")
{
return;
}
}
}
}
context.ReportDiagnostic(Diagnostic.Create(AwaitTaskTask, context.Node.GetLocation(), type.Name));
}