feat: Add SetHelpExitCode to allow custom exit codes on help

[maishivamhoo123]

Description

Addresses issue #2338.

Currently, cmd --help returns exit code 0. This causes scripts using eval $(cmd) to crash because the shell tries to execute the help text as commands. This PR allows developers to set a custom exit code (e.g., 2) when help is invoked, preventing this behavior.

Changes

• Added helpExitCode field to Command struct.
• Added SetHelpExitCode(int) method.
• Updated ExecuteC to return a specific error if helpExitCode is set and help is invoked.
• Added unit test TestHelpExitCode.

Example Usage

rootCmd.SetHelpExitCode(2)
// Running "app --help" will now print usage and exit with code 2

[CLAassistant]

All committers have signed the CLA.

[ccoVeille]

This won't work the way you think.

It won't return the expected exit code.

It will only return exit 1 and an error message.

Note: I'm not saying the feature is a bad idea (or a good one).

I'm just saying it doesn't do work

[maishivamhoo123]

@ccoVeille Thank you for the guidance! I've updated the logic to use a custom ExitError struct. This ensures the specific integer code can be retrieved via errors.As instead of defaulting to a generic error 1.

Apologies for the oversight in the previous commit. I would appreciate your review when you have a moment.
Looking for guidance.
Thank you sir.

[ccoVeille]

This won't work either...

Take a look at CheckErr method and how code use it.

I feel like your PR requires more iterations. Adding a feature like this to such a project might not be easy.

let's wait for @marckhouzam and his feedback

But if you have a need for this, maybe you could simply consider defining a custom helper command to your code using cobra (so without change in cobra) and then call os.Exit with the code you want.