yargs the modern, pirate-themed, successor to optimist.. Use when: commands and (grouped) options (`my-program.js serve --port=5000`); a dynamically generated help menu based on your arguments:; generate completion scripts for Bash and Zsh for your command. NOT for: web browser UI rendering; server-side HTML generation.
yargs the modern, pirate-themed, successor to optimist.. It gives you: commands and (grouped) options (my-program.js serve --port=5000).
npm install yargs
mocha [spec..]
Run tests with Mocha
Commands
mocha inspect [spec..] Run tests with Mocha [default]
mocha init <path> create a client-side Mocha setup at <path>
Rules & Behavior
--allow-uncaught Allow uncaught errors to propagate [boolean]
--async-only, -A Require all tests to use a callback (async) or
return a Promise [boolean]
npm i yargs@next
#!/usr/bin/env node
import yargs from 'yargs';
import { hideBin } from 'yargs/helpers';
const argv = yargs(hideBin(process.argv)).parse()
if (argv.ships > 3 && argv.distance < 53.5) {
console.log('Plunder more riffiwobbles!')
} else {
console.log('Retreat from the xupptumblers!')
}
$ ./plunder.js --ships=4 --distance=22
Plunder more riffiwobbles!
$ ./plunder.js --ships 12 --distance 98.7
Retreat from the xupptumblers!
#!/usr/bin/env node
import yargs from 'yargs';
import { hideBin } from 'yargs/helpers';
yargs(hideBin(process.argv))
.command('serve [port]', 'start the server', (yargs) => {
return yargs
.positional('port', {
describe: 'port to bind on',
default: 5000
})
}, (argv) => {
if (argv.verbose) console.info(`start server on :${argv.port}`)
serve(argv.port)
})
.option('verbose', {
alias: 'v',
type: 'boolean',
description: 'Run with verbose logging'
})
.parse()
#!/usr/bin/env node
import yargs from 'yargs';
import { hideBin } from 'yargs/helpers';
yargs(hideBin(process.argv))
.command('serve [port]', 'start the server', (yargs) => {
return yargs
.positional('port', {
describe: 'port to bind on',
default: 5000
})
}, (argv) => {
if (argv.verbose) console.info(`start server on :${argv.port}`)
serve(argv.port)
})
.option('verbose', {
alias: 'v',
type: 'boolean',
description: 'Run with verbose logging'
})
.parse()
npm i -D @types/yargs.hideBin is a shorthand for process.argv.slice(2). It has the benefit that it takes into account variations in some environments, e.g., Electron.-deno flag on the end, like @17.7.2-deno