未选择命令时如何创建 yargs 默认响应

Question

I have created a CLI with yargs . It has a series of nested commands. All the commands work nicely, but I also want to have a welcome/info message when no command is given or if a command that does not exist is supplied.

I have been unable to get this to work, what efforts I have used either display a message all the time or not at all. Any suggestions would be welcome

Answer 1

Took quite a lot of docs reading but got there in the end, the $0 is used as a catch all command and can be added to the builder.

yargs(hideBin(process.argv))
  .version(require('../package.json').version)
  .alias('h', 'help')
  .help()
  .command('stuff', 'makes stuff happen', () => {}, (_) => {
    ...
  })
  .command('$0', 'the default command', () => {}, (_) => {
    console.log(defaultMessage)
  })
  .parse();