harness_coverage_hook.rb

module HarnessCoverageHook
  def run_podfile_post_install_hooks
    super

    pods = resolve_coverage_pods
    return if pods.empty?

    Pod::UI.puts "[HarnessCoverage] Instrumenting pods for native coverage: #{pods.join(', ')}"

    apply_coverage_flags_to_pods(pods)
    enable_harness_coverage_pod
    apply_linker_flags
  end

  private

  def resolve_coverage_pods
    project_dir = Dir.pwd
    config_json = `node -e "
      import('#{project_dir}/rn-harness.config.mjs')
        .then(m => console.log(JSON.stringify(
          m.default?.coverage?.native?.ios?.pods || []
        )))
        .catch(() => console.log('[]'))
    "`.strip
    JSON.parse(config_json)
  rescue => e
    Pod::UI.warn "[HarnessCoverage] Failed to read config: #{e.message}"
    []
  end

  def apply_coverage_flags_to_pods(pods)
    pods_project.targets.each do |target|
      next unless pods.include?(target.name)

      target.build_configurations.each do |config|
        swift_flags = config.build_settings['OTHER_SWIFT_FLAGS'] || '$(inherited)'
        unless swift_flags.include?('-profile-generate')
          config.build_settings['OTHER_SWIFT_FLAGS'] =
            "#{swift_flags} -profile-generate -profile-coverage-mapping"
        end

        c_flags = config.build_settings['OTHER_CFLAGS'] || '$(inherited)'
        unless c_flags.include?('-fprofile-instr-generate')
          config.build_settings['OTHER_CFLAGS'] =
            "#{c_flags} -fprofile-instr-generate -fcoverage-mapping"
        end
      end

      Pod::UI.puts "[HarnessCoverage]   -> #{target.name}"
    end
  end

  def enable_harness_coverage_pod
    pods_project.targets.each do |target|
      next unless target.name == 'HarnessCoverage'

      target.build_configurations.each do |config|
        swift_conditions = config.build_settings['SWIFT_ACTIVE_COMPILATION_CONDITIONS'] || '$(inherited)'
        unless swift_conditions.include?('HARNESS_COVERAGE')
          config.build_settings['SWIFT_ACTIVE_COMPILATION_CONDITIONS'] =
            "#{swift_conditions} HARNESS_COVERAGE"
        end

        gcc_defs = config.build_settings['GCC_PREPROCESSOR_DEFINITIONS'] || '$(inherited)'
        unless gcc_defs.include?('HARNESS_COVERAGE')
          config.build_settings['GCC_PREPROCESSOR_DEFINITIONS'] =
            "#{gcc_defs} HARNESS_COVERAGE=1"
        end
      end
    end
  end

  def apply_linker_flags
    pods_project.targets.each do |target|
      target.build_configurations.each do |config|
        ldflags = config.build_settings['OTHER_LDFLAGS'] || '$(inherited)'
        unless ldflags.include?('-fprofile-instr-generate')
          config.build_settings['OTHER_LDFLAGS'] =
            "#{ldflags} -fprofile-instr-generate"
        end
      end
    end
  end
end

Pod::Installer.prepend(HarnessCoverageHook)