Flipper should not get built on iOS release builds

Hello,

As pointed by someone else in a related issue, when adding Flipper to a React-Native project (or I guess any project), building times get significantly increased. This is not desirable.

Impact: longer build times https://github.com/react-native-community/discussions-and-proposals/issues/226

Proposed solution: I’m thinking about adding flag DISABLE_FLIPPER, and wrap all files with #ifndef DISABLE_FLIPPER. I guess that would definitely help, but requires patching dependencies as well. Thoughts?

[andreialecu]

I’m not sure why this wasn’t proposed yet, but a simple ENV variable can help with this.

  if !ENV['CI']
    use_flipper!
    post_install do |installer|
      flipper_post_install(installer)
    end
  end

On CircleCI the above tweak resulted in dropping build times from about 14 minutes to 8 minutes.

[TPXP]

I dug some more into this today. It seems we cannot inject custom definitions when working with Cocoapods anyway, since the only one (“Debug”) is hardcoded, and configuration definition does not take into account the target for which the configuration is generated (see https://github.com/CocoaPods/CocoaPods/blob/56538172fac99b410046812df67087a8829a7019/lib/cocoapods/project.rb#L379).

This issue of pods being built even if not used in the configuration has already been raised to Cocoapods: https://github.com/CocoaPods/CocoaPods/issues/9658#issuecomment-605874654 . A few things have been attempted, but nothing landed yet.

I guess we’ll have to implement a few things on Cocoapods before we can make progress on this.