commander-remaining-args/src/index.js

Get the remaining unknown arguments after parsing the CLI with commander.js

module.exports = cli =>
  cli.rawArgs
    // Only retain elements starting from the first --option
    .reduce(
      (acc, item) => acc.length || item.startsWith('-') ? [...acc, item] : acc,
      []
    )
    // Filter out arguments already parsed by commander.js
    .filter((rawArg, index, rawArgs) => {
      // --option=B, --oB
      const matches = rawArg.match(/^(--.+)=(.+)$/) || rawArg.match(/^(-[^-])(.+)$/);
      if (matches) {
        const [, option] = matches;
        if (cli.optionFor(option)) {
          return false;
        } else {
          return true;
        }
      }

      // If the option is consumed by commander.js, then we skip it
      if (cli.optionFor(rawArg)) {
        return false;
      }

      // If it's an argument of an option consumed by commander.js, then we
      // skip it too
      const previousRawArg = rawArgs[index - 1];
      const previousOption = cli.optionFor(previousRawArg);
      if (previousOption) { // Option consumed by commander.js
        const previousKey = previousOption.attributeName();
        if (cli[previousKey] === rawArg) {
          return false;
        }
      }

      return true;
    });