static bool TryGetDiagnostic(SyntaxNodeAnalysisContext nodeContext, out Diagnostic diagnostic)
{
diagnostic = default(Diagnostic);
var anyInvoke = nodeContext.Node as InvocationExpressionSyntax;
var info = nodeContext.SemanticModel.GetSymbolInfo(anyInvoke);
IMethodSymbol anyResolve = info.Symbol as IMethodSymbol;
if (anyResolve == null)
{
anyResolve = info.CandidateSymbols.OfType <IMethodSymbol>().FirstOrDefault(candidate => HasPredicateVersion(candidate));
}
if (anyResolve == null || !HasPredicateVersion(anyResolve))
{
return(false);
}
ExpressionSyntax target, followUp;
TypeSyntax type;
ParameterSyntax param;
if (ReplaceWithOfTypeAnyAnalyzer.MatchSelect(anyInvoke, out target, out type, out param, out followUp))
{
// if (member == "Where" && followUp == null) return;
diagnostic = Diagnostic.Create(
descriptor,
anyInvoke.GetLocation()
);
return(true);
}
return(false);
}
static bool HasPredicateVersion(IMethodSymbol member)
{
if (!ReplaceWithOfTypeAnyAnalyzer.IsQueryExtensionClass(member.ContainingType))
{
return(false);
}
return(member.Name == "LastOrDefault");
}
public async override Task RegisterCodeFixesAsync(CodeFixContext context)
{
var document = context.Document;
var cancellationToken = context.CancellationToken;
var span = context.Span;
var diagnostics = context.Diagnostics;
var root = await document.GetSyntaxRootAsync(cancellationToken).ConfigureAwait(false);
var diagnostic = diagnostics.First();
var node = root.FindNode(context.Span, getInnermostNodeForTie: true) as InvocationExpressionSyntax;
var newRoot = root.ReplaceNode(node, ReplaceWithOfTypeAnyAnalyzer.MakeOfTypeCall(node));
context.RegisterCodeFix(CodeActionFactory.Create(node.Span, diagnostic.Severity, "Replace with call to OfType<T>().LongCount()", document.WithSyntaxRoot(newRoot)), diagnostic);
}
