feature: support more group flags

[YoniRomm]

I had a use cases where I needed:

1. I had 2 group of flags and I needed that one flag from each group will be presented (but together something like MarkFlagsRequiredTogether but between 2 groups)
2. enforce the flag value to be from a list of options
3. enforce exactly 1 flag to be presented from a group (similar to MarkFlagsMutuallyExclusive)

[marevers]

I recently opened a PR #1952 which should address point 3.

[marevers]

@YoniRomm My PR should actually address point 1 as well. You can create two flag groups and set MarkFlagsOneRequired and MarkFlagsMutuallyExclusive for both. This will enforce at least one flag and not more than one from each group.

The only thing not covered is 2, which, if I understand correctly is not about the flag itself (its name) but its value? I think there is no way to do that currently out-of-the-box, but you could also implement your own logic to check if the flag value comes from a list of expected options.

[gabguy]

@marevers MarkFlagsOneRequired function does not exist on the latest release (1.7.0).
It was added under commit c81c46a, but there is no tag that includes this addition.
Can you please create another release with this code in it?

[marevers]

@gabguy I am not a maintainer, so I cannot create releases. I do know, however, that the addition of MarkFlagsOneRequired is planned for the next release (1.8.0).

[marevers]

@YoniRomm @gabguy 1.8.0 was released which contains the feature: https://github.com/spf13/cobra/releases/tag/v1.8.0
So this can now be closed.