DualOptions

Kind: Class

Source: lib/option.js

This class is to make it easier to work with dual options, without changing the existing implementation. We support separate dual options for separate positive and negative options, like --build and --no-build, which share a single option value. This works nicely for some use cases, but is tricky for others where we want separate behaviours despite the single shared option value.

DualOptions manages paired positive and negative CLI options that share the same option attribute, such as --build and --no-build. It determines the value represented by the option that was supplied, allowing the parser to preserve distinct behavior for each side of a dual option.

Methods

Where it refuses work

• DualOptions stops the work with an early return when !this.dualOptions.has(optionKey).

Diagram

mermaid
graph LR
  A[CLI input] --> B[Option]
  B --> C[DualOptions]
  C --> D[valueFromOption]
  D --> E[Shared option value]

Usage

js
import { Command } from 'commander';

const program = new Command();

program
  .option('--build', 'enable build output')
  .option('--no-build', 'disable build output');

program.parse();

const options = program.opts();

if (options.build) {
  console.log('Build output is enabled.');
} else {
  console.log('Build output is disabled.');
}

AI Coding Instructions

• Treat DualOptions as parser support code for positive and negative options that map to the same attribute.
• Keep paired option names aligned, such as --build and --no-build, so they resolve to the same option value.
• Use valueFromOption() when converting a parsed option occurrence into its stored value.
• Do not assume a negative option always means the parsed value is false; preserve the option-specific behavior handled by this class.

Used by

1 reference from 1 file. Each is a place in this repository where the symbol is actually used — go read one rather than trusting an example.

Imported by (1)

• Command — lib/command.js:14