dotnet-installer/src/dotnet/ParseResultExtensions.cs

// Copyright (c) .NET Foundation and contributors. All rights reserved.
// Licensed under the MIT license. See LICENSE file in the project root for full license information.

using System;
using System.Linq;
using Microsoft.DotNet.Cli.CommandLine;

namespace Microsoft.DotNet.Cli
{
    public static class ParseResultExtensions
    {
        public static void ShowHelp(this ParseResult parseResult) =>
            Console.WriteLine(parseResult.Command().HelpView());

        public static void ShowHelpOrErrorIfAppropriate(this ParseResult parseResult)
        {
            if (parseResult.Errors.Any())
            {
                throw new CommandParsingException(
                    string.Join(Environment.NewLine,
                                parseResult.Errors.Select(e => e.Message)));
            }

            if (parseResult.AppliedCommand().HasOption("help"))
            {
                // NOTE: this is a temporary stage in refactoring toward the ClicCommandLineParser being used at the CLI entry point. 
                throw new HelpException(parseResult.Command().HelpView());
            }
        }
    }
}