Exclude pod when porting to mac with catalyst

Question

Porting apps to mac is finally possible thanks to Catalyst, problem is, numerous pods don't support AppKit. Most common one would be Crashlytics / Firebase.

In [...]/Pods/Crashlytics/iOS/Crashlytics.framework/Crashlytics(CLSInternalReport.o), building for Mac Catalyst, but linking in object file built for iOS Simulator, file '[...]/Pods/Crashlytics/iOS/Crashlytics.framework/Crashlytics' for architecture x86_64

Since it's a recent topic, I couldn't find doc on how to remove a pod from my build for macOS but keep it for iOS and iPadOS.

It is possible to use in code:

#if !targetEnvironment(macCatalyst) 
// Code to exclude for your macOS app
#endif

But that one part of the problem, the other part is to link the pod only for iOS...

What would be the easiest/best course of action when the library is not vital for macOS but still wanted on iOS?

Answer 1

For the best approach of handling unsupported framweorks for Catalyst, you guys should read the solution of Fernando Moya de Rivas, he has a github with a solution here with more up to date information.

He basically said you just need to define an array of all of the libs you don't want to install on mac osx, like this: ['Fabric', 'Crashlytics', 'Firebase/Core', ...].

Then, your pod file can look simple as this:

# Podfile
load 'remove_unsupported_libraries.rb'

target 'My target' do
   use_frameworks!
   # Install your pods
   pod ...
end

# define unsupported pods
def catalyst_unsupported_pods
    ['Fabric', 'Crashlytics', 'Firebase/Core', ...]
end

# Remove unsupported pods from your project
post_install do |installer|   
    installer.configure_support_catalyst
end

Answer 2

Following @ajgryc answer, I was able to make a sleek solution:

In your podfile add

post_install do |installer|
    installer.pods_project.targets.each do |target|
        if target.name == "Pods-[Name of Project]"
            puts "Updating #{target.name} OTHER_LDFLAGS to OTHER_LDFLAGS[sdk=iphone*]"
            target.build_configurations.each do |config|
                xcconfig_path = config.base_configuration_reference.real_path
                xcconfig = File.read(xcconfig_path)
                new_xcconfig = xcconfig.sub('OTHER_LDFLAGS =', 'OTHER_LDFLAGS[sdk=iphone*] =')
                File.open(xcconfig_path, "w") { |file| file << new_xcconfig }
            end
        end
    end
end

Since Cocoapods 1.8.4

post_install do |installer|
  installer.pods_project.targets.each do |target|
    if target.name == "Pods-[Name of Project]"
      puts "Updating #{target.name} to exclude Crashlytics/Fabric"
      target.build_configurations.each do |config|
        xcconfig_path = config.base_configuration_reference.real_path
        xcconfig = File.read(xcconfig_path)
        xcconfig.sub!('-framework "Crashlytics"', '')
        xcconfig.sub!('-framework "Fabric"', '')
        new_xcconfig = xcconfig + 'OTHER_LDFLAGS[sdk=iphone*] = -framework "Crashlytics" -framework "Fabric"'
        File.open(xcconfig_path, "w") { |file| file << new_xcconfig }
      end
    end
  end
end

And then in run script build phase for Fabric:

if [[$ARCHS != "x86_64"]]; then
  "${PODS_ROOT}/Fabric/run" [your usual key]
fi

Answer 3

Open your Pods-$projectname.release.xcconfig file in your project's Pods directory, and locate the OTHER_LDFLAGS line. Add [sdk=iphone*] immediately after the variable name (as an example, mine now looks like this):

OTHER_LDFLAGS[sdk=iphone*] = $(inherited) -ObjC -l"MailCore-ios" -l"c++" -l"iconv" -l"resolv" -l"xml2" -l"z"

That conditionally sets the link options only when building iphone variants, preventing the pod from being linked on OSX. Of course as you mention, this needs to be combined with #if !targetEnvironment(macCatalyst) and #endif surrounding the code calling the pod or you'll get linker errors.

This allowed me to get past the same problem. (And in case you're wondering what other cool things besides conditional variables you can add to your .xcconfig files, here's a reference I found: https://pewpewthespells.com/blog/xcconfig_guide.html )