public static ITypeSymbol DetermineParameterType(
this ArgumentSyntax argument,
SemanticModel semanticModel,
CancellationToken cancellationToken)
{
TypeInfo typeInfo;
if (argument.Declaration != null)
{
typeInfo = semanticModel.GetTypeInfo(argument.Declaration.Type);
return typeInfo.Type?.IsErrorType() == false ? typeInfo.Type : semanticModel.Compilation.ObjectType;
}
// If a parameter appears to have a void return type, then just use 'object'
// instead.
typeInfo = semanticModel.GetTypeInfo(argument.Expression, cancellationToken);
if (typeInfo.Type != null && typeInfo.Type.SpecialType == SpecialType.System_Void)
{
return semanticModel.Compilation.ObjectType;
}
return semanticModel.GetType(argument.Expression, cancellationToken);
}