private static bool IsMethodOrderByExtension(InvocationExpressionSyntax invocation, SemanticModel semanticModel)
{
if (invocation == null)
{
return(false);
}
var methodSymbol = semanticModel.GetSymbolInfo(invocation).Symbol as IMethodSymbol;
return(methodSymbol != null &&
methodSymbol.Name == "OrderBy" &&
methodSymbol.MethodKind == MethodKind.ReducedExtension &&
CollectionEmptinessChecking.MethodIsOnIEnumerable(methodSymbol, semanticModel));
}
public override void Initialize(AnalysisContext context)
{
context.RegisterSyntaxNodeActionInNonGenerated(
c =>
{
var outerInvocation = (InvocationExpressionSyntax)c.Node;
var outerMethodSymbol = c.SemanticModel.GetSymbolInfo(outerInvocation).Symbol as IMethodSymbol;
if (outerMethodSymbol == null ||
!CollectionEmptinessChecking.MethodIsOnIEnumerable(outerMethodSymbol, c.SemanticModel))
{
return;
}
InvocationExpressionSyntax innerInvocation;
if (outerMethodSymbol.MethodKind == MethodKind.ReducedExtension)
{
var memberAccess = outerInvocation.Expression as MemberAccessExpressionSyntax;
if (memberAccess == null)
{
return;
}
innerInvocation = memberAccess.Expression as InvocationExpressionSyntax;
}
else
{
var argument = outerInvocation.ArgumentList.Arguments.FirstOrDefault();
if (argument == null)
{
return;
}
innerInvocation = argument.Expression as InvocationExpressionSyntax;
}
if (innerInvocation == null)
{
return;
}
var innerMethodSymbol = c.SemanticModel.GetSymbolInfo(innerInvocation).Symbol as IMethodSymbol;
if (innerMethodSymbol == null ||
!CollectionEmptinessChecking.MethodIsOnIEnumerable(innerMethodSymbol, c.SemanticModel))
{
return;
}
var outerArguments = GetReducedArguments(outerMethodSymbol, outerInvocation);
if (CheckForSimplifiable(outerArguments, outerMethodSymbol, innerMethodSymbol, c,
innerInvocation))
{
return;
}
if (CheckForCastSimplification(outerMethodSymbol, innerMethodSymbol, innerInvocation,
outerInvocation, c))
{
return;
}
},
SyntaxKind.InvocationExpression);
}