Support Shakapacker 8.x

Author: laramee

README.md

@@ -150,7 +150,7 @@ Given the example above, we can perform a deploy by running `bundle exec rake de
 4. Clean any outdated or unused assets from S3 using `S3AssetDeploy`
 
 ## Customizing local asset collection
-By default, `S3AssetDeploy::Manager` will use [`S3AssetDeploy::RailsLocalAssetCollector`](https://github.com/Loomly/s3_asset_deploy/blob/main/lib/s3_asset_deploy/rails_local_asset_collector.rb) to collect locally compiled assets. This will use the `Sprockets::Manifest` and `Webpacker` config (if `Webpacker` is installed) to locate the compiled assets. `S3AssetDeploy::RailsLocalAssetCollector` inherits from the [`S3AssetDeploy::LocalAssetCollector`](https://github.com/Loomly/s3_asset_deploy/blob/main/lib/s3_asset_deploy/local_asset_collector.rb) base class. You can completely customize how your local assets are collected for deploys by creating your own class that inherits from `S3AssetDeploy::LocalAssetCollector` and passing it into the manager. You'll want override `S3AssetDeploy::LocalAssetCollector#assets` in your custom collector such that it returns an array of `S3AssetDeploy::LocalAsset` instances. Here's a basic example:
+By default, `S3AssetDeploy::Manager` will use [`S3AssetDeploy::RailsLocalAssetCollector`](https://github.com/Loomly/s3_asset_deploy/blob/main/lib/s3_asset_deploy/rails_local_asset_collector.rb) to collect locally compiled assets. This will use the `Sprockets::Manifest` and `Webpacker`/`Shakapacker` config (if either are installed) to locate the compiled assets. `S3AssetDeploy::RailsLocalAssetCollector` inherits from the [`S3AssetDeploy::LocalAssetCollector`](https://github.com/Loomly/s3_asset_deploy/blob/main/lib/s3_asset_deploy/local_asset_collector.rb) base class. You can completely customize how your local assets are collected for deploys by creating your own class that inherits from `S3AssetDeploy::LocalAssetCollector` and passing it into the manager. You'll want override `S3AssetDeploy::LocalAssetCollector#assets` in your custom collector such that it returns an array of `S3AssetDeploy::LocalAsset` instances. Here's a basic example:
 
 
 ```ruby

lib/s3_asset_deploy/rails_local_asset_collector.rb

@@ -22,10 +22,11 @@ def assets_from_manifest
   end
 
   def pack_assets
-    return [] unless defined?(::Webpacker)
+    return [] unless defined?(::Shakapacker) || defined?(::Webpacker)
 
     Dir.chdir(public_path) do
-      packs_dir = ::Webpacker.config.public_output_path.relative_path_from(public_path)
+      config = defined?(::Shakapacker) ? ::Shakapacker.config : ::Webpacker.config
+      packs_dir = config.public_output_path.relative_path_from(public_path)
 
       Dir[File.join(packs_dir, "/**/**")]
         .select { |path| File.file?(path) }