Simplify the dependencies migration for new libraries

Summary:
When it comes to migrate existing libraries, users needs to update their .podspec files with a bunch [of changes](https://reactnative.dev/docs/0.69/new-architecture-library-ios#add-folly-and-other-dependencies).
This diff groups those changes in a single function, so that contributors can just invoke that function to prepare their dependencies.

## Changelog:

[iOS][Changed] Add function to simplify podspecs

Differential Revision: D39312203

fbshipit-source-id: 85998e1ed6881a353fed2da0ddd013bc3cc4b2ee

Author: Riccardo Cipolleschi

packages/rn-tester/NativeComponentExample/MyNativeView.podspec

@@ -7,8 +7,6 @@ require "json"
 
 package = JSON.parse(File.read(File.join(__dir__, "../" "package.json")))
 
-folly_compiler_flags = '-DFOLLY_NO_CONFIG -DFOLLY_MOBILE=1 -DFOLLY_USE_LIBCPP=1 -Wno-comma -Wno-shorten-64-to-32'
-folly_version = '2021.07.22.00'
 boost_version = '1.76.0'
 boost_compiler_flags = '-Wno-documentation'
 
@@ -20,23 +18,18 @@ Pod::Spec.new do |s|
   s.homepage        = "https://github.com/sota000/my-native-view.git"
   s.license         = "MIT"
   s.platforms       = { :ios => "12.4", :tvos => "12.4" }
-  s.compiler_flags  = folly_compiler_flags + ' ' + boost_compiler_flags + ' -Wno-nullability-completeness'
+  s.compiler_flags  = boost_compiler_flags + ' -Wno-nullability-completeness'
   s.author          = "Facebook, Inc. and its affiliates"
   s.source          = { :git => "https://github.com/facebook/my-native-view.git", :tag => "#{s.version}" }
   s.pod_target_xcconfig    = {
-    "HEADER_SEARCH_PATHS" => "\"$(PODS_ROOT)/boost\" \"$(PODS_ROOT)/RCT-Folly\" \"$(PODS_ROOT)/boost\" \"${PODS_CONFIGURATION_BUILD_DIR}/React-Codegen/React_Codegen.framework/Headers\"",
+    "HEADER_SEARCH_PATHS" => "\"$(PODS_ROOT)/RCT-Folly\" \"$(PODS_ROOT)/boost\" \"${PODS_CONFIGURATION_BUILD_DIR}/React-Codegen/React_Codegen.framework/Headers\"",
     "CLANG_CXX_LANGUAGE_STANDARD" => "c++17"
   }
 
   s.source_files    = "ios/**/*.{h,m,mm,cpp}"
   s.requires_arc    = true
 
-  s.dependency "React"
-  s.dependency "React-RCTFabric"
-  s.dependency "React-Codegen"
-  s.dependency "RCTRequired"
-  s.dependency "RCTTypeSafety"
-  s.dependency "ReactCommon/turbomodule/core"
+  install_modules_dependencies(s, use_fabric: true)
 
   # Enable codegen for this library
   use_react_native_codegen!(s, {

packages/rn-tester/NativeModuleExample/ScreenshotManager.podspec

@@ -7,9 +7,6 @@ require "json"
 
 package = JSON.parse(File.read(File.join(__dir__, "../package.json")))
 
-folly_compiler_flags = '-DFOLLY_NO_CONFIG -DFOLLY_MOBILE=1 -DFOLLY_USE_LIBCPP=1 -Wno-comma -Wno-shorten-64-to-32'
-folly_version = '2021.07.22.00'
-
 Pod::Spec.new do |s|
   s.name            = "ScreenshotManager"
   s.version         = package["version"]
@@ -18,15 +15,14 @@ Pod::Spec.new do |s|
   s.homepage        = "https://github.com/facebook/react-native.git"
   s.license         = "MIT"
   s.platforms       = { :ios => "12.4", :tvos => "12.4" }
-  s.compiler_flags  = folly_compiler_flags + ' -Wno-nullability-completeness'
+  s.compiler_flags  = '-Wno-nullability-completeness'
   s.author          = "Facebook, Inc. and its affiliates"
   s.source          = { :git => "https://github.com/facebook/react-native.git", :tag => "#{s.version}" }
 
   s.source_files    = "**/*.{h,m,mm,swift}"
   s.requires_arc    = true
 
-  s.dependency "React-Core"
-  s.dependency "RCT-Folly", folly_version
+  install_modules_dependencies(s, use_fabric: false)
 
   # s.dependency "..."
 

scripts/cocoapods/__tests__/new_architecture-test.rb

@@ -7,6 +7,7 @@
 require_relative "../new_architecture.rb"
 require_relative "./test_utils/InstallerMock.rb"
 require_relative "./test_utils/PodMock.rb"
+require_relative "./test_utils/SpecMock.rb"
 
 class NewArchitectureTests < Test::Unit::TestCase
     def teardown
@@ -109,6 +110,60 @@ def test_modifyFlagsForNewArch_whenOnNewArch_updateFlags
         assert_equal(yoga_debug_config.build_settings["OTHER_CPLUSPLUSFLAGS"], "$(inherited)")
         assert_equal(yoga_release_config.build_settings["OTHER_CPLUSPLUSFLAGS"], "$(inherited)")
     end
+
+    # =================================== #
+    # Test - install Modules Dependencies #
+    # =================================== #
+    def test_installModulesDependencies_whenFabricEnabledAndNoSearchPathsNorCompilerFlagsArePresent_itInstallDependencies
+        #  Arrange
+        spec = SpecMock.new
+
+        # Act
+        NewArchitectureHelper.install_modules_dependencies(spec)
+
+        # Assert
+        assert_equal(spec.compiler_flags, NewArchitectureHelper.folly_compiler_flags)
+        assert_equal(spec.pod_target_xcconfig["HEADER_SEARCH_PATHS"], "\"$(PODS_ROOT)/boost\"")
+        assert_equal(
+            spec.dependencies,
+            [
+                "React-Core",
+                "React-RCTFabric",
+                "React-Codegen",
+                "RCT-Folly",
+                "RCTRequired",
+                "RCTTypeSafety",
+                "ReactCommon/turbomodule/core"
+        ])
+    end
+
+    def test_installModulesDependencies_whenFabricEnabledAndSearchPathsAndCompilerFlagsArePresent_itInstallDependenciesAndPreserveOtherSettings
+        #  Arrange
+        spec = SpecMock.new
+        spec.compiler_flags = '-Wno-nullability-completeness'
+        other_flags = "\"$(PODS_ROOT)/RCT-Folly\" \"$(PODS_ROOT)/boost\" \"${PODS_CONFIGURATION_BUILD_DIR}/React-Codegen/React_Codegen.framework/Headers\""
+        spec.pod_target_xcconfig = {
+            "HEADER_SEARCH_PATHS" => other_flags
+        }
+        use_fabric = false
+
+        # Act
+        NewArchitectureHelper.install_modules_dependencies(spec, use_fabric: use_fabric)
+
+        # Assert
+        assert_equal(spec.compiler_flags, "-Wno-nullability-completeness #{NewArchitectureHelper.folly_compiler_flags}")
+        assert_equal(spec.pod_target_xcconfig["HEADER_SEARCH_PATHS"], "#{other_flags} \"$(PODS_ROOT)/boost\"")
+        assert_equal(
+            spec.dependencies,
+            [
+                "React-Core",
+                "React-Codegen",
+                "RCT-Folly",
+                "RCTRequired",
+                "RCTTypeSafety",
+                "ReactCommon/turbomodule/core"
+        ])
+    end
 end
 
 # ================ #

scripts/cocoapods/__tests__/test_utils/SpecMock.rb

@@ -0,0 +1,28 @@
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+#
+# This source code is licensed under the MIT license found in the
+# LICENSE file in the root directory of this source tree.
+
+class SpecMock
+
+    attr_accessor :compiler_flags
+    attr_accessor :pod_target_xcconfig
+    attr_reader :dependencies
+
+    def initialize
+        @compiler_flags = ""
+        @pod_target_xcconfig = Hash.new
+        @dependencies = []
+    end
+
+    def dependency(dependency_name)
+        @dependencies.push(dependency_name)
+    end
+
+    def to_hash
+        return {
+            "compiler_flags" => @compiler_flags,
+            "pod_target_xcconfig" => @pod_target_xcconfig,
+        }
+    end
+end

scripts/cocoapods/new_architecture.rb

@@ -4,8 +4,11 @@
 # LICENSE file in the root directory of this source tree.
 
 class NewArchitectureHelper
+    @@shared_flags = "-DFOLLY_NO_CONFIG -DFOLLY_MOBILE=1 -DFOLLY_USE_LIBCPP=1"
 
-    @@new_arch_cpp_flags = '$(inherited) -DRCT_NEW_ARCH_ENABLED=1 -DFOLLY_NO_CONFIG -DFOLLY_MOBILE=1 -DFOLLY_USE_LIBCPP=1'
+    @@folly_compiler_flags = "#{@@shared_flags} -Wno-comma -Wno-shorten-64-to-32"
+
+    @@new_arch_cpp_flags = "$(inherited) -DRCT_NEW_ARCH_ENABLED=1 #{@@shared_flags}"
 
     def self.set_clang_cxx_language_standard_if_needed(installer)
         language_standard = nil
@@ -56,4 +59,34 @@ def self.modify_flags_for_new_architecture(installer, is_new_arch_enabled)
             end
         end
     end
+
+    def self.install_modules_dependencies(spec, use_fabric: true)
+        # Pod::Specification does not have getters so, we have to read
+        # the existing values from a hash representation of the object.
+        hash = spec.to_hash
+
+        compiler_flags = hash["compiler_flags"] ? hash["compiler_flags"] : ""
+        current_config = hash["pod_target_xcconfig"] != nil ? hash["pod_target_xcconfig"] : {}
+        current_headers = current_config["HEADER_SEARCH_PATHS"] != nil ? current_config["HEADER_SEARCH_PATHS"] : ""
+
+        boost_search_path = "\"$(PODS_ROOT)/boost\""
+
+        spec.compiler_flags = compiler_flags.empty? ? @@folly_compiler_flags : "#{compiler_flags} #{@@folly_compiler_flags}"
+        current_config["HEADER_SEARCH_PATHS"] = current_headers.empty? ? boost_search_path : "#{current_headers} #{boost_search_path}"
+        spec.pod_target_xcconfig = current_config
+
+        spec.dependency "React-Core"
+        if use_fabric
+            spec.dependency "React-RCTFabric" # This is for Fabric Component
+        end
+        spec.dependency "React-Codegen"
+        spec.dependency "RCT-Folly"
+        spec.dependency "RCTRequired"
+        spec.dependency "RCTTypeSafety"
+        spec.dependency "ReactCommon/turbomodule/core"
+    end
+
+    def self.folly_compiler_flags
+        return @@folly_compiler_flags
+    end
 end

scripts/react_native_pods.rb

@@ -131,6 +131,23 @@ def use_react_native! (
   end
 end
 
+# Getter to retrieve the folly flags in case contributors need to apply them manually.
+#
+# Returns: the folly compiler flags
+def folly_flags()
+  return NewArchitectureHelper.folly_compiler_flags
+end
+
+# This function can be used by library developer to prepare their modules for the New Architecture.
+# It passes the Folly Flags to the module, it configures the search path and installs some New Architecture specific dependencies.
+#
+# Parameters:
+# - spec: The spec that has to be configured with the New Architecture code
+# - use_fabric: Whether the module should depends on `Fabric``. Defaults to `true`
+def install_modules_dependencies(spec, use_fabric: true)
+  NewArchitectureHelper.install_modules_dependencies(spec, use_fabric: use_fabric)
+end
+
 # It returns the default flags.
 def get_default_flags()
   return ReactNativePodsUtils.get_default_flags()