refactor(AssetVariant) extract asset build & path logic

Author: rmosolgo

lib/react/rails.rb

@@ -1,3 +1,4 @@
-require 'react/rails/railtie'
+require 'react/rails/asset_variant'
 require 'react/rails/engine'
+require 'react/rails/railtie'
 require 'react/rails/view_helper'

lib/react/rails/asset_variant.rb

@@ -0,0 +1,19 @@
+module React
+  module Rails
+    class AssetVariant
+      GEM_ROOT = Pathname.new('../../../../').expand_path(__FILE__)
+      attr_reader :react_build, :react_directory, :jsx_directory
+
+      def initialize(options={})
+        # We want to include different files in dev/prod. The development builds
+        # contain console logging for invariants and logging to help catch
+        # common mistakes. These are all stripped out in the production build.
+        @react_build = options[:variant] == :production ? 'production' : 'development'
+        options[:addons] && @react_build += '-with-addons'
+
+        @react_directory = GEM_ROOT.join('lib/assets/react-source/').join(@react_build).to_s
+        @jsx_directory =   GEM_ROOT.join('lib/assets/javascripts/').to_s
+      end
+    end
+  end
+end

lib/react/rails/railtie.rb

@@ -33,25 +33,25 @@ class Railtie < ::Rails::Railtie
       end
 
       initializer "react_rails.bust_cache", group: :all do |app|
-        variant = app.config.react.variant == :production ? 'production' : 'development'
-        variant += '-with-addons' if app.config.react.addons
+        asset_variant = React::Rails::AssetVariant.new({
+          variant: app.config.react.variant,
+          addons: app.config.react.addons,
+        })
 
         app.assets.version = [
           app.assets.version,
-          "react-#{variant}",
+          "react-#{asset_variant.react_build}",
         ].compact.join('-')
       end
 
       config.before_initialize do |app|
-        # We want to include different files in dev/prod. The development builds
-        # contain console logging for invariants and logging to help catch
-        # common mistakes. These are all stripped out in the production build.
-        root_path = Pathname.new('../../../../').expand_path(__FILE__)
-        directory = app.config.react.variant == :production ? 'production' : 'development'
-        directory += '-with-addons' if app.config.react.addons
+        asset_variant = React::Rails::AssetVariant.new({
+          variant: app.config.react.variant,
+          addons: app.config.react.addons,
+        })
 
-        app.config.assets.paths << root_path.join('lib/assets/react-source/').join(directory).to_s
-        app.config.assets.paths << root_path.join('lib/assets/javascripts/').to_s
+        app.config.assets.paths << asset_variant.react_directory
+        app.config.assets.paths << asset_variant.jsx_directory
       end
 
       config.after_initialize do |app|

test/react/rails/asset_variant_test.rb

@@ -0,0 +1,25 @@
+require 'test_helper'
+
+class AssetVariantTest < ActiveSupport::TestCase
+  def build_variant(options)
+    React::Rails::AssetVariant.new(options)
+  end
+
+  test 'it points to different directories for react' do
+    production_variant = build_variant(variant: :production)
+    assert_match(%r{/lib/assets/react-source/production}, production_variant.react_directory)
+
+    development_variant = build_variant(variant: nil)
+    assert_match(%r{/lib/assets/react-source/development}, development_variant.react_directory)
+  end
+
+  test 'points to jsx transformer' do
+    variant = build_variant({})
+    assert_match(%r{/lib/assets/javascripts/}, variant.jsx_directory)
+  end
+
+  test 'it includes addons if requested' do
+    asset_variant = build_variant(addons: true)
+    assert_equal "development-with-addons", asset_variant.react_build
+  end
+end