PowerArgs.Cli.PowerArgsRichCommandLineReader.FindOldTabCompletionHooks C# (CSharp) Method

        private static IEnumerable<ITabCompletionSource> FindOldTabCompletionHooks(CommandLineArgumentsDefinition definition)
        {
            List<ITabCompletionSource> completionSources = new List<ITabCompletionSource>();

            if (definition.Metadata.HasMeta<TabCompletion>() && definition.Metadata.Meta<TabCompletion>().CompletionSourceType != null && definition.Metadata.Meta<TabCompletion>().CompletionSourceType.GetInterfaces().Contains(typeof(ITabCompletionSource)))
            {
                completionSources.Add((ITabCompletionSource)Activator.CreateInstance(definition.Metadata.Meta<TabCompletion>().CompletionSourceType));
            }

            foreach (var argument in definition.AllGlobalAndActionArguments)
            {
                foreach (var argSource in argument.Metadata.Metas<ArgumentAwareTabCompletionAttribute>())
                {
                    var source = argSource.CreateTabCompletionSource(definition, argument);
                    if (source is ITabCompletionSource)
                    {
                        completionSources.Insert(0, (ITabCompletionSource)source);
                    }
                }
            }

            return completionSources;
        }