Add color support for help option

[hcodes]

No description provided.

[hcodes]

As example:

[shadowspawn]

This has gathered a few likes over the years, so not closing quite yet. I have some problems with choosing colors:

• color choice is quite personal
• color support in some Windows shells is poor
• light and dark themed shells makes color choice harder

I suspect it is too much trouble to build in directly, but perhaps commander can make it easier for people to customise the help output.

[trusktr]

Sywac isn't well documented, but it has a way to specify colors like this:

// See http://sywac.io
const cli = require('sywac')

cli
  .string('-c, --cloudEnv <env>', {
    description: `The cloud env to use.`,
    required: true,
  })
  .version('-v, --version')
  .help('-h, --help')
  .showHelpByDefault()
  // Add colors to the help output!
  .style({
    usagePrefix: str => chalk().yellow(str.slice(0, 6)) + ' ' + chalk().bold(str.slice(7)),
    usageCommandPlaceholder: str => chalk().bold(str),
    usagePositionals: str => chalk().bold(str),
    usageArgsPlaceholder: str => chalk().bold(str),
    usageOptionsPlaceholder: str => chalk().bold(str),
    group: str => chalk().yellow(str),
    flags: str => chalk().bold(str),
    desc: str => chalk().cyan(str),
    hints: str => chalk().gray.dim(str),
    groupError: str => chalk().red.bold(str),
    flagsError: str => chalk().red.bold(str),
    descError: str => chalk().red.bold(str),
    hintsError: str => chalk().red(str),
    messages: str => chalk().red.bold(str), // these are error messages
  })
  .parseAndExit()
  .then(main)
  .catch(e => {
    console.error(e)
    process.exit(1)
  })

let c
function chalk() {
  // lazily load chalk, only used if help text displayed
  if (!c) c = require('chalk')
  return c
}

async function main(opts) {
  const {cloudEnv} = opts
  console.log(cloudEnv)
}

Example output with color:

It'd be neat to have some sort of color configurability for Commander.

[ivands]

It would still be nice to have a more simple api to change colors & styles

[onury]

IMO, color support is crucial for a CLI tool.
I understand the "no dependency" policy. commander should not do it itself,
but at least provide a legal & easy way for the user.

// user code:
import { Command } from 'commander';
import c from 'chalk';

const formatter = {
  helpWidth: 120,
  indent: 2,
  titles: str => c.yellow.bold(str),
  usage: str => c.gray(str),
  option: flags => c.green(flags),
  command: (name, args) => c.green(name) + '  ' + c.gray(args),
  description: desc => c.white(desc),
  default: val => `[default: ${c.gray(val)}}`
};

const program = new Command();
program
  .name('colorful-cli')
  .usage('<command> [options]')
  .version(pkg.version)
  .format(formatter)            // <—— pass formatter object to commander
  .option('--debug', 'output extra logs')
  // ... more commands & options...

Pls re-open this issue.

[shadowspawn]

This old issue has been getting recent upvotes, and I have started looking at what is needed to make it easier for authors to provide custom colours in the help. I'll reopen at least while I am working on it.

[shadowspawn]

Open draft PR in #2251. Added a style layer of simple hooks so don't need to subclass to add colour:

program.configureHelp({
  styleTitle: (str) => styleText('bold', str),
  styleCommandText: (str) => styleText('cyan', str),
  styleCommandDescription: (str) => styleText('magenta', str),
  styleItemDescription: (str) => styleText('italic', str),
  styleOptionText: (str) => styleText('green', str),
  styleArgumentText: (str) => styleText('yellow', str),
  styleSubcommandText: (str) => styleText('blue', str),
});

[shadowspawn]

A prerelease is available for v13. The release is tagged as next and can be installed with:

npm install commander@next