doc(ios): install cocoapods with homebrew

[GitToTheHub]

• cocoapods are not installable with the current system ruby version on macOS. When trying to install with sudo gem install cocoapods, the error message will appear: securerandom requires Ruby version >= 3.1.0. The current ruby version is 2.6.10.210.
• On stackoverflow it is suggested to install it instead with homebrew: https://stackoverflow.com/questions/77339560/error-installing-cocoapodsdrb-requires-ruby-version-2-7-0-the-current-ruby

Platforms affected

macOS

Motivation and Context

I tried to setup my machine and got an error when installing cocoa pods

Description

Testing

Checklist

• I've run the tests to see all new and existing tests pass
• I added automated test coverage as appropriate for this change
• Commit is prefixed with (platform) if this change only applies to one platform (e.g. (android))
• If this Pull Request resolves an issue, I linked to the issue in the text above (and used the correct keyword to close issues using keywords)
• I've updated the documentation if necessary

[erisu]

Do we know if CocoaPods manages the Homebrew package, or is it handled by a third party?

The current guide follows the steps provided on the official CocoaPods website.

In fact, CocoaPods does not recommend using the default macOS system Ruby. Instead, it suggests using a Ruby version manager to install a newer version. For example, the rvm package, which can be installed via Homebrew.

In my case, I have a newer version of Ruby installed on macOS:

% ruby -v
ruby 3.3.6 (2024-11-05 revision 75015d4c1f) [arm64-darwin23]

Here is their official installation guide, which recommends using a Ruby version manager:
https://guides.cocoapods.org/using/getting-started.html#installation

[GitToTheHub]

The homebrew package is maintained by homebrew itself: https://github.com/Homebrew/homebrew-core/blob/447e92edf265af365ed4fd3feb5abcb2d204a956/Formula/c/cocoapods.rb

If we use the Cocoapods recommendation I would change the documentation to first load a recent ruby version by brew install ruby and then installing Cocoapods by gem install cocoapods.

[erisu]

I think it should be OK to update the guide to use brew install cocoapods.

It seems,

• When running brew install cocoapods, Homebrew uses a portable version of Ruby.
  • Requirement for Ruby comes from the depends_on "ruby" line in the formula.
• It downloads the CocoaPods tarball from the CocoaPods repository.
• This tarball contains the cocoapods.gemspec file, which is then built and installed.

I'm not 100% sure, but if a user had installed Ruby via brew, would Homebrew use that version instead of the portable version?

At the very least, it seems to ignore the older system's default Ruby, as your PR description suggests its resolved the securerandom requires Ruby version >= 3.1.0. The current ruby version is 2.6.10.210 issue.

I'll wait a bit to see if anyone else has questions or comments. But other than that, I think it's OK to merge.

[GitToTheHub]

Cool, thanks for the explanation. I learned a little bit :)

[NiklasMerz]

I'm fine with that. Most Mac users should have brew and using it is much more reliable.