Colouring fails in options

[GHNewbiee]

The following works:

  .option(`${chalk.cyan('-c')}, --config [file]`, 'the file name')

but not the next one:

  .option(`${chalk.cyan('-c')}, ${chalk.cyan('--config [file]')}`, 'the file name')

It returns:

/.../node_modules/commander/lib/option.js:181
    return str + word[0].toUpperCase() + word.slice(1);

Tia

[shadowspawn]

First, the problem. Commander is using that first parameter to determine:

• short flag -c
• long flag --config
• whether has option argument [file]
• whether option-argument is required or optional

Commander uses some simple code to pull apart the parameter. Colouring the text is inserting a bunch of ascii escape sequences into the string, and that is not going to go well...

I tried your first example to check, and although the short flag is displayed in cyan in the help, it does not work on command line.

% node index.js -c fhf
error: unknown option '-c'

[shadowspawn]

The way to change the format of the help is to modify the Help class, either by a subclass or by overriding individual methods using configureHelp().

See: https://github.com/tj/commander.js#more-configuration-2

For your case, the option flags are supplied by the optionTerm method:

program.configureHelp({
  optionTerm: (option) => {
    return chalk.cyan(option.flags);
  }
});

[GHNewbiee]

For your case, the option flags are supplied by the optionTerm method:

I am not sure I fully understand.

In the following option

  .option('-v, --verbose', 'verbosity that can be increased', increaseVerbosity, 0)

there are 5 parts or 4 arguments:

• -v (as a part),
• --verbose (as a part)
• -v, --verbose (as an argument)
• verbosity that can be increased
• increaseVerbosity
• 0

Please, clarify which method can format each part/argument. Tia

[shadowspawn]

The Help class has methods for what is displayed in the help. The two methods used for each option are .optionTerm() and .optionDescription(). If your colour customisation fits into that pattern, you could supply a custom version of those routines.

The Help class takes the Option created by:

.option('-v, --verbose', 'verbosity that can be increased', increaseVerbosity, 0)

and displays it in the help as "term" and "description":

  -v, --verbose        verbosity that can be increased (default: 0)

The Option class has properties for: short, long, flags, description, parseArg, defaultValue and more.

The default implementation of Help.optionTerm() is:

  optionTerm(option) {
    return option.flags;
  }

[shadowspawn]

For interest, reopened: #301