copyInheritedSettings and configureOutput have side-effects

[mmkal]

Hi - noticed something that maybe isn't desired behaviour with the above two methods. Since copyInheritedSettings sets this._outputConfiguration = sourceCommand._outputConfiguration and configureOutput does Object.assign(...) - this means that one command can change another command's settings unexpectedly:

import {program, Command} from 'commander'

const one = new Command('one')
  .description('A very very very very very very very very very very very very very very very very very very very very very very very very long description')
  .action(() => console.log('hi i am one'))
  .configureOutput({
    writeOut: str => console.log(str + '🚀🚀🚀🚀'),
    getOutHelpWidth: () => 70,
  })

const two = new Command('two')
  .copyInheritedSettings(one)
  .description('Another very very very very very very very very very very very very very very very very very very very very very very very very long description')
  .action(() => console.log('hi i am two'))
  .configureOutput({
    getOutHelpWidth: () => 200,
  })

program
  .addCommand(one)
  .addCommand(two)

program.parse()

When you do mycommand one --help it uses 200 for the help width, not 70 as I'd expect. (Note: mycommand two --help prints the 🚀🚀🚀🚀 at the bottom, which is correct/expected, IMO).

Suggested solution: use a spread operator in either/both of the methods.

[shadowspawn]

Probably uncommon to configure the output at a leaf command, but the side-effect isn't the intended behaviour. .configureOutput() should merge to a new object instead of merging in place.

This will change the behaviour for people configuring output after setting up subcommands (not the intended pattern), which can be touched on in the release notes. (Note to self: check README too.)

[shadowspawn]

This has been released in Commander v14.