private static AnalysisResult HasConfigureAwaitFalse(AwaitExpressionSyntax awaitNode)
{
InvocationExpressionSyntax configureAwaitExpression = FindConfigureAwaitExpression(awaitNode);
bool hasConfigureAwaitFalse = configureAwaitExpression != null && IsExpressionConfigureAwaitFalse(configureAwaitExpression);
return(new AnalysisResult(hasConfigureAwaitFalse, awaitNode.GetLocation()));
}
public static CheckerResult CheckNode(AwaitExpressionSyntax awaitNode, SemanticModel semanticModel)
{
var location = awaitNode.GetLocation();
var possibleConfigureAwait = FindExpressionForConfigureAwait(awaitNode);
if (possibleConfigureAwait != null && IsConfigureAwait(possibleConfigureAwait.Expression))
{
if (HasFalseArgument(possibleConfigureAwait.ArgumentList))
{
return(new CheckerResult(CheckerProblem.NoProblem, location));
}
else
{
return(new CheckerResult(CheckerProblem.ConfigureAwaitWithTrue, location));
}
}
else
{
var can = CanHaveConfigureAwait(awaitNode.Expression, semanticModel);
var problem = can
? CheckerProblem.MissingConfigureAwaitFalse
: CheckerProblem.NoProblem;
return(new CheckerResult(problem, location));
}
}
private static CheckResult CheckNode(AwaitExpressionSyntax awaitNode)
{
var possibleConfigureAwait = FindExpressionForConfigureAwait(awaitNode);
var good = possibleConfigureAwait != null && IsConfigureAwait(possibleConfigureAwait.Expression) && HasFalseArgument(possibleConfigureAwait.ArgumentList);
return(new CheckResult(good, awaitNode.GetLocation()));
}
public static CheckerResult CheckNode(AwaitExpressionSyntax awaitNode)
{
var possibleConfigureAwait = FindExpressionForConfigureAwait(awaitNode);
var good = possibleConfigureAwait != null && IsProperConfigureAwait(possibleConfigureAwait);
return(new CheckerResult(good, awaitNode.GetLocation()));
}
private static bool HasPreviousConfigureAwait(SyntaxNodeAnalysisContext context, AwaitExpressionSyntax node)
{
// Find all previous awaits with ConfiguredAwait(false)
// Use context.SemanticModel.AnalyzeControlFlow to check if the current await is accessible from one of the previous await
// https://joshvarty.com/2015/03/24/learn-roslyn-now-control-flow-analysis/
var method = node.FirstAncestorOrSelf <MethodDeclarationSyntax>();
if (method != null)
{
var otherAwaitExpressions = method.DescendantNodes(_ => true).OfType <AwaitExpressionSyntax>();
foreach (var expr in otherAwaitExpressions)
{
if (HasPreviousConfigureAwait(expr))
{
return(true);
}
bool HasPreviousConfigureAwait(AwaitExpressionSyntax otherAwaitExpression)
{
if (otherAwaitExpression == node)
{
return(false);
}
if (otherAwaitExpression.GetLocation().SourceSpan.Start > node.GetLocation().SourceSpan.Start)
{
return(false);
}
if (!IsConfiguredTaskAwaitable(context, otherAwaitExpression))
{
return(false);
}
var nodeStatement = node.FirstAncestorOrSelf <StatementSyntax>();
var parentStatement = otherAwaitExpression.Ancestors().OfType <StatementSyntax>().FirstOrDefault();
while (parentStatement != null && nodeStatement != parentStatement)
{
if (!IsEndPointReachable(context, parentStatement))
{
return(false);
}
parentStatement = parentStatement.Ancestors().OfType <StatementSyntax>().FirstOrDefault();
}
return(true);
}
}
}
return(false);
}
public static CheckerResult CheckNode(AwaitExpressionSyntax awaitNode, SemanticModel semanticModel)
{
var possibleConfigureAwait = FindExpressionForConfigureAwait(awaitNode);
if (possibleConfigureAwait != null && IsConfigureAwait(possibleConfigureAwait.Expression))
{
if (HasFalseArgument(possibleConfigureAwait.ArgumentList))
{
return(new CheckerResult(false, awaitNode.GetLocation()));
}
else
{
return(new CheckerResult(true, awaitNode.GetLocation()));
}
}
else
{
var can = CanHaveConfigureAwait(awaitNode.Expression, semanticModel);
return(new CheckerResult(can, awaitNode.GetLocation()));
}
}
public static CheckerResult CheckNode(AwaitExpressionSyntax awaitNode)
{
var possibleConfigureAwait = FindExpressionForConfigureAwait(awaitNode);
var good = possibleConfigureAwait != null && IsProperConfigureAwait(possibleConfigureAwait);
return new CheckerResult(good, awaitNode.GetLocation());
}
private Location GetLocationForDiagnostic(AwaitExpressionSyntax awaitExpression)
{
return(awaitExpression.GetLocation());
}
