CliFx/CliFx/Exceptions/CliFxException.cs

using System;

namespace CliFx.Exceptions;

/// <summary>
/// Exception thrown when there is an error during application execution.
/// </summary>
public partial class CliFxException : Exception
{
    internal const int DefaultExitCode = 1;

    // Regular `exception.Message` never returns null, even if
    // it hasn't been set.
    internal string? ActualMessage { get; }

    /// <summary>
    /// Returned exit code.
    /// </summary>
    public int ExitCode { get; }

    /// <summary>
    /// Whether to show the help text before exiting.
    /// </summary>
    public bool ShowHelp { get; }

    /// <summary>
    /// Initializes an instance of <see cref="CliFxException"/>.
    /// </summary>
    public CliFxException(
        string message,
        int exitCode = DefaultExitCode,
        bool showHelp = false,
        Exception? innerException = null)
        : base(message, innerException)
    {
        ActualMessage = message;
        ExitCode = exitCode;
        ShowHelp = showHelp;
    }
}

public partial class CliFxException
{
    // Internal errors don't show help because they're meant for the developer
    // and not the end-user of the application.
    internal static CliFxException InternalError(string message, Exception? innerException = null) =>
        new(message, DefaultExitCode, false, innerException);

    // User errors are typically caused by invalid input and they're meant for
    // the end-user, so we want to show help.
    internal static CliFxException UserError(string message, Exception? innerException = null) =>
        new(message, DefaultExitCode, true, innerException);
}