v8.0.0

Added

• .argument(name, description) for adding command-arguments (#1490)
  • supports default value for optional command-arguments (#1508)
  • supports custom processing function (#1508)
• .createArgument() factory method (#1497)
• .addArgument() (#1490)
• Argument supports .choices() (#1525)
• .showHelpAfterError() to display full help or a custom message after an error (#1534)
• .hook() with support for 'preAction' and 'postAction' callbacks (#1514)
• client typing of .opts() return type using TypeScript generics (#1539)
• the number of command-arguments is checked for programs without an action handler (#1502)
• .getOptionValue() and .setOptionValue() (#1521)

Changed

• refactor and simplify TypeScript declarations (with no default export) (#1520)
• .parseAsync() is now declared as async (#1513)
• Breaking: Help method .visibleArguments() returns array of Argument (#1490)
• Breaking: Commander 8 requires Node.js 12 or higher (#1500)
• Breaking: CommanderError code commander.invalidOptionArgument renamed commander.invalidArgument (#1508)
• Breaking: TypeScript declaration for .addTextHelp() callback no longer allows result of undefined, now just string (#1516)
• refactor index.tab into a file per class (#1522)
• remove help suggestion from "unknown command" error message (see .showHelpAfteError()) (#1534)
• Command property .arg initialised to empty array (was previously undefined) (#1529)
• update dependencies

Deprecated

• second parameter of cmd.description(desc, argDescriptions) for adding argument descriptions (#1490)
  • (use new .argument(name, description) instead)
• InvalidOptionArgumentError (replaced by InvalidArgumentError) (#1508)

Removed

• Breaking: TypeScript declaration for default export of global Command object (#1520)
  • (still available as named program export)

Migration Tips

If you have a simple program without an action handler, you will now get an error if
there are missing command-arguments.

program
  .option('-d, --debug')
  .arguments('<file>');
program.parse();

$ node trivial.js 
error: missing required argument 'file'

If you want to show the help in this situation, you could check the arguments before parsing:

if (process.argv.length === 2)
  program.help();
program.parse();

Or, you might choose to show the help after any user error:

program.showHelpAfterError();

8.0.0-2

Added

• .showHelpAfterError() to display full help or a custom message after an error (#1534)
• custom argument processing function also called without action handler (only with action handler in v8.0.0-0) (#1529)

Changed

• remove help suggestion from "unknown command" error message (see .showHelpAfteError()) (#1534)
• Command property .arg initialised to empty array (was previously undefined) (#1529)

8.0.0-1

Added

• .addArgument() (#1490)
• Argument supports .choices() (#1525)
• client typing of .opts() return type using TypeScript generics (#1539)

Changed

• refactor index.tab into a file per class (#1522)
• update dependencies

8.0.0-0

Added

• .getOptionValue() and .setOptionValue() (#1521)
• .hook() with support for 'preAction' and 'postAction' callbacks (#1514)
• .argument(name, description) for adding command-arguments (#1490)
  • supports default value for optional command-arguments (#1508)
  • supports custom processing function (#1508)
• .createArgument() factory method (#1497)
• the number of command-arguments is checked for programs without an action handler (#1502)

Changed

• refactor and simplify TypeScript declarations (with no default export) (#1520)
• .parseAsync() is now declared as async (#1513)
• Breaking: Help method .visibleArguments() returns array of Argument (#1490)
• Breaking: Commander 8 requires Node.js 12 or higher (#1500)
• Breaking: CommanderError code commander.invalidOptionArgument renamed commander.invalidArgument (#1508)
• Breaking: TypeScript declaration for .addTextHelp() callback no longer allows result of undefined, now just string (#1516)

Deprecated

• second parameter of cmd.description(desc, argDescriptions) for adding argument descriptions (#1490)
  • (use new .argument(name, description) instead)
• InvalidOptionArgumentError (replaced by InvalidArgumentError) (#1508)

Removed

• Breaking: TypeScript declaration for default export of global Command object (#1520)
  • (still available as named program export)

v7.2.0

Added

• TypeScript typing for parent property on Command (#1475)
• TypeScript typing for .attributeName() on Option (#1483)
• support information in package (#1477)

Changed

• improvements to error messages, README, and tests
• update dependencies

v7.1.0

Added

• support for named imports from ECMAScript modules (#1440)
• add .cjs to list of expected script file extensions (#1449)
• allow using option choices and variadic together (#1454)

Fixed

• replace use of deprecated process.mainModule (#1448)
• regression for legacy command('*') and call when command line includes options (#1464)
• regression for on('command:*', ...) and call when command line includes unknown options (#1464)
• display best error for combination of unknown command and unknown option (i.e. unknown command) (#1464)

Changed

• make TypeScript typings tests stricter (#1453)
• improvements to README and tests

v7.0.0

Added

• .enablePositionalOptions() to let program and subcommand reuse same option (#1427)
• .passThroughOptions() to pass options through to other programs without needing -- (#1427)
• .allowExcessArguments(false) to show an error message if there are too many command-arguments on command line for the action handler (#1409)
• .configureOutput() to modify use of stdout and stderr or customise display of errors (#1387)
• use .addHelpText() to add text before or after the built-in help, for just current command or also for all subcommands (#1296)
• enhance Option class (#1331)
  • allow hiding options from help
  • allow restricting option arguments to a list of choices
  • allow setting how default value is shown in help
• .createOption() to support subclassing of automatically created options (like .createCommand()) (#1380)
• refactor the code generating the help into a separate public Help class (#1365)
  • support sorting subcommands and options in help
  • support specifying wrap width (columns)
  • allow subclassing Help class
  • allow configuring Help class without subclassing

Changed

• Breaking: options are stored safely by default, not as properties on the command (#1409)
  • this especially affects accessing options on program, use program.opts()
  • revert behaviour with .storeOptionsAsProperties()
• Breaking: action handlers are passed options and command separately (#1409)
• deprecated callback parameter to .help() and .outputHelp() (removed from README) (#1296)
• Breaking: errors now displayed using process.stderr.write() instead of console.error()
• deprecate .on('--help') (removed from README) (#1296)
• initialise the command description to empty string (previously undefined) (#1365)
• document and annotate deprecated routines (#1349)

Fixed

• wrapping bugs in help (#1365)
  • first line of command description was wrapping two characters early
  • pad width calculation was not including help option and help command
  • pad width calculation was including hidden options and commands
• improve backwards compatibility for custom command event listeners (#1403)

Deleted

• Breaking: .passCommandToAction() (#1409)
  • no longer needed as action handler is passed options and command
• Breaking: "extra arguments" parameter to action handler (#1409)
  • if being used to detect excess arguments, there is now an error available by setting .allowExcessArguments(false)

Migration Tips

The biggest change is the parsed option values. Previously the options were stored by default as properties on the command object, and now the options are stored separately.

If you wish to restore the old behaviour and get running quickly you can call .storeOptionsAsProperties().
To allow you to move to the new code patterns incrementally, the action handler will be passed the command twice,
to match the new "options" and "command" parameters (see below).

program options

Use the .opts() method to access the options. This is available on any command but is used most with the program.

program.option('-d, --debug');
program.parse();
// Old code before Commander 7
if (program.debug) console.log(`Program name is ${program.name()}`);

// New code
const options = program.opts();
if (options.debug) console.log(`Program name is ${program.name()}`);

action handler

The action handler gets passed a parameter for each command-argument you declared. Previously by default the next parameter was the command object with the options as properties. Now the next two parameters are instead the options and the command. If you
only accessed the options there may be no code changes required.

program
  .command('compress <filename>')
  .option('-t, --trace')
  // Old code before Commander 7
  .action((filename, cmd) => {
    if (cmd.trace) console.log(`Command name is ${cmd.name()}`);
  });

  // New code
  .action((filename, options, command) => {
    if (options.trace) console.log(`Command name is ${command.name()}`);
  });

If you already set .storeOptionsAsProperties(false) you may still need to adjust your code.

program
  .command('compress <filename>')
  .storeOptionsAsProperties(false)
  .option('-t, --trace')
  // Old code before Commander 7
  .action((filename, command) => {
    if (command.opts().trace) console.log(`Command name is ${command.name()}`);
  });

   // New code
   .action((filename, options, command) => {
      if (command.opts().trace) console.log(`Command name is ${command.name()}`);
   });

7.0.0-2

Changed

• Breaking: options are stored safely by default, not as properties on the command (#1409)
  • this especially affects accessing options on program, use program.opts()
  • revert behaviour with .storeOptionsAsProperties()
• Breaking: action handlers are passed options and command separately (#1409)

Added

• Breaking: error message if there are too many command-arguments on command line for the action handler (#1409)
  • if should be allowed then declare extra arguments, or use .allowExcessArguments()

Deleted

• Breaking: .passCommandToAction() (#1409)
  • no longer needed as action handler is passed options and command
• Breaking: "extra arguments" parameter to action handler (#1409)
  • if being used to detect excess arguments, there is now an error displayed by default

Migration Tips

The biggest change is the parsed option values. Previously the options were stored by default as properties on the command object, and now the options are stored separately.

If you wish to restore the old behaviour and get running quickly you can call .storeOptionsAsProperties().
To allow you to move to the new code patterns incrementally, the action handler will be passed the command twice,
to match the new "options" and "command" parameters (see below).

program options

Use the .opts() method to access the options. This is available on any command but is used most with the program.

program.option('-d, --debug');
program.parse();
// Old code before Commander 7
if (program.debug) console.log(`Program name is ${program.name()}`);

// New code
const options = program.opts();
if (options.debug) console.log(`Program name is ${program.name()}`);

action handler

The action handler gets passed a parameter for each command-argument you declared. Previously by default the next parameter was the command object with the options as properties. Now the next two parameters are instead the options and the command. If you
only accessed the options there may be no code changes required.

program
  .command('compress <filename>')
  .option('-t, --trace')
  // Old code before Commander 7
  .action((filename, cmd)) => {
    if (cmd.trace) console.log(`Command name is ${cmd.name()}`);
  });

  // New code
  .action((filename, options, command)) => {
    if (options.trace) console.log(`Command name is ${command.name()}`);
  });

If you already set .storeOptionsAsProperties(false) you may still need to adjust your code.

program
  .command('compress <filename>')
  .storeOptionsAsProperties(false)
  .option('-t, --trace')
  // Old code before Commander 7
  .action((filename, command)) => {
    if (command.opts().trace) console.log(`Command name is ${command.name()}`);
  });

   // New code
   .action((filename, options, command)) => {
      if (command.opts().trace) console.log(`Command name is ${command.name()}`);
   });

v6.2.1

Fixed

• some tests failed if directory path included a space (1390)

v7.0.0-1

Added

• .createOption() to support subclassing of automatically created options (like .createCommand()) (#1380)
• .configureOutput() to modify use of stdout and stderr or customise display of errors (#1387)

Breaking changes relative to 7.0.0-0

• rework new Help.wrap() for simpler usage pattern (#1395)
• rename new "columns" properties (#1396)
  • Help.columns -> helpWidth
  • getOutColumns() -> getOutHelpWidth()
  • getErrColumns() -> getErrHelpWidth()