private int?HandlePreviewDirective(ApplicationSchema applicationSchema, CommandLineInput commandLineInput)
{
var isPreviewMode = _configuration.IsPreviewModeAllowed && commandLineInput.IsPreviewDirectiveSpecified;
if (!isPreviewMode)
{
return(null);
}
var commandSchema = applicationSchema.TryFindCommand(commandLineInput, out var argumentOffset);
_console.Output.WriteLine("Parser preview:");
// Command name
if (commandSchema != null && argumentOffset > 0)
{
_console.WithForegroundColor(ConsoleColor.Cyan, () =>
_console.Output.Write(commandSchema.Name));
_console.Output.Write(' ');
}
// Parameters
foreach (var parameter in commandLineInput.Arguments.Skip(argumentOffset))
{
_console.Output.Write('<');
_console.WithForegroundColor(ConsoleColor.White, () =>
_console.Output.Write(parameter));
_console.Output.Write('>');
_console.Output.Write(' ');
}
// Options
foreach (var option in commandLineInput.Options)
{
_console.Output.Write('[');
_console.WithForegroundColor(ConsoleColor.White, () =>
_console.Output.Write(option));
_console.Output.Write(']');
_console.Output.Write(' ');
}
_console.Output.WriteLine();
return(0);
}
private int?HandleHelpOption(ApplicationSchema applicationSchema, CommandLineInput commandLineInput)
{
// Help is rendered either when it's requested or when the user provides no arguments and there is no default command
var shouldRenderHelp =
commandLineInput.IsHelpOptionSpecified ||
!applicationSchema.Commands.Any(c => c.IsDefault) && !commandLineInput.Arguments.Any() && !commandLineInput.Options.Any();
if (!shouldRenderHelp)
{
return(null);
}
// Get the command schema that matches the input or use a dummy default command as a fallback
var commandSchema =
applicationSchema.TryFindCommand(commandLineInput) ??
CommandSchema.StubDefaultCommand;
RenderHelp(applicationSchema, commandSchema);
return(0);
}
private async ValueTask <int> RunAsync(ApplicationSchema applicationSchema, CommandInput commandInput)
{
// Handle debug directive
if (IsDebugModeEnabled(commandInput))
{
await PromptDebuggerAsync();
}
// Handle preview directive
if (IsPreviewModeEnabled(commandInput))
{
_console.Output.WriteCommandInput(commandInput);
return(0);
}
// Try to get the command schema that matches the input
var commandSchema =
applicationSchema.TryFindCommand(commandInput.CommandName) ??
applicationSchema.TryFindDefaultCommand() ??
FallbackDefaultCommand.Schema;
// Activate command instance
var commandInstance = commandSchema == FallbackDefaultCommand.Schema
? new FallbackDefaultCommand() // bypass activator
: (ICommand)_typeActivator.CreateInstance(commandSchema.Type);
// Assemble help context
var helpContext = new HelpContext(
Metadata,
applicationSchema,
commandSchema,
commandSchema.GetValues(commandInstance)
);
// Handle help option
if (ShouldShowHelpText(commandSchema, commandInput))
{
_console.Output.WriteHelpText(helpContext);
return(0);
}
// Handle version option
if (ShouldShowVersionText(commandSchema, commandInput))
{
_console.Output.WriteLine(Metadata.Version);
return(0);
}
// Starting from this point, we may produce exceptions that are meant for the
// end user of the application (i.e. invalid input, command exception, etc).
// Catch these exceptions here, print them to the console, and don't let them
// propagate further.
try
{
// Bind and execute command
_commandBinder.Bind(commandInput, commandSchema, commandInstance);
await commandInstance.ExecuteAsync(_console);
return(0);
}
catch (CliFxException ex)
{
_console.Error.WriteException(ex);
if (ex.ShowHelp)
{
_console.Output.WriteLine();
_console.Output.WriteHelpText(helpContext);
}
return(ex.ExitCode);
}
}