Move application.tailwind.css to a dir ignored by propshaft

This file should not be included in the stylesheet link tags served to
user agents.

Fixes #470

Author: flavorjones

lib/install/install_tailwindcss.rb

@@ -1,5 +1,6 @@
 APPLICATION_LAYOUT_PATH             = Rails.root.join("app/views/layouts/application.html.erb")
 CENTERING_CONTAINER_INSERTION_POINT = /^\s*<%= yield %>/.freeze
+TAILWIND_ASSET_PATH                 = Rails.root.join("app/assets/tailwind")
 
 if APPLICATION_LAYOUT_PATH.exist?
   unless File.read(APPLICATION_LAYOUT_PATH).match?(/stylesheet_link_tag :app/)
@@ -31,9 +32,9 @@
   append_to_file(".gitignore", %(\n/app/assets/builds/*\n!/app/assets/builds/.keep\n))
 end
 
-unless Rails.root.join("app/assets/stylesheets/application.tailwind.css").exist?
-  say "Add default app/assets/stylesheets/application.tailwind.css"
-  copy_file "#{__dir__}/application.tailwind.css", "app/assets/stylesheets/application.tailwind.css"
+unless TAILWIND_ASSET_PATH.join("application.tailwind.css").exist?
+  say "Add default #{TAILWIND_ASSET_PATH}/application.tailwind.css"
+  copy_file "#{__dir__}/application.tailwind.css", TAILWIND_ASSET_PATH.join("application.tailwind.css")
 end
 
 if Rails.root.join("Procfile.dev").exist?

lib/install/upgrade_tailwindcss.rb

@@ -1,6 +1,8 @@
 TAILWIND_CONFIG_PATH = Rails.root.join("config/tailwind.config.js")
 APPLICATION_LAYOUT_PATH = Rails.root.join("app/views/layouts/application.html.erb")
 POSTCSS_CONFIG_PATH = Rails.root.join("config/postcss.config.js")
+OLD_TAILWIND_ASSET_PATH = Rails.root.join("app/assets/stylesheets")
+TAILWIND_ASSET_PATH = Rails.root.join("app/assets/tailwind")
 
 unless TAILWIND_CONFIG_PATH.exist?
   say "Default tailwind.config.js is missing!", :red
@@ -14,7 +16,8 @@
 
 if POSTCSS_CONFIG_PATH.exist?
   say "Moving PostCSS configuration to application root directory"
-  FileUtils.mv(POSTCSS_CONFIG_PATH, Rails.root, verbose: true) || abort
+  copy_file POSTCSS_CONFIG_PATH, Rails.root.join("postcss.config.js")
+  remove_file POSTCSS_CONFIG_PATH
 end
 
 if APPLICATION_LAYOUT_PATH.exist?
@@ -35,6 +38,12 @@
   say %(        Please check your layouts and remove any "inter-font" stylesheet links.)
 end
 
+if OLD_TAILWIND_ASSET_PATH.join("application.tailwind.css").exist?
+  say "Moving application.tailwind.css to #{TAILWIND_ASSET_PATH}"
+  copy_file OLD_TAILWIND_ASSET_PATH.join("application.tailwind.css"), TAILWIND_ASSET_PATH.join("application.tailwind.css")
+  remove_file OLD_TAILWIND_ASSET_PATH.join("application.tailwind.css")
+end
+
 if system("npx --version")
   say "Running the upstream Tailwind CSS upgrader"
   command = Shellwords.join(["npx", "@tailwindcss/upgrade@next", "--force", "--config", TAILWIND_CONFIG_PATH.to_s])

lib/tailwindcss/commands.rb

@@ -8,7 +8,7 @@ def compile_command(debug: false, **kwargs)
 
         command = [
           Tailwindcss::Ruby.executable(**kwargs),
-          "-i", rails_root.join("app/assets/stylesheets/application.tailwind.css").to_s,
+          "-i", rails_root.join("app/assets/tailwind/application.tailwind.css").to_s,
           "-o", rails_root.join("app/assets/builds/tailwind.css").to_s,
         ]
 

lib/tailwindcss/engine.rb

@@ -6,6 +6,10 @@ class Engine < ::Rails::Engine
       Rails.application.config.generators.stylesheets = false
     end
 
+    initializer "tailwindcss.exclude_asset_path", after: "propshaft.append_assets_path" do
+      Rails.application.config.assets.excluded_paths << Rails.root.join("app/assets/tailwind")
+    end
+
     config.app_generators do |g|
       g.template_engine :tailwindcss
     end

test/integration/user_install_test.sh

@@ -37,7 +37,7 @@ bin/rails tailwindcss:install
 
 # TEST: tailwind was installed correctly
 grep -q "<main class=\"container" app/views/layouts/application.html.erb
-test -a app/assets/stylesheets/application.tailwind.css
+test -a app/assets/tailwind/application.tailwind.css
 
 # TEST: rake tasks don't exec (#188)
 cat <<EOF >> Rakefile

test/integration/user_upgrade_test.sh

@@ -75,10 +75,12 @@ if grep -q inter-font app/views/layouts/application.html.erb ; then
 fi
 
 # TEST: moving the postcss file
-if [ ! -f postcss.config.js ] ; then
-  echo "FAIL: postcss.config.js not moved"
-  exit 1
-fi
+test ! -a config/postcss.config.js
+test   -a postcss.config.js
+
+# TEST: moving application.tailwind.css
+test ! -a app/assets/stylesheets/application.tailwind.css
+test   -a app/assets/tailwind/application.tailwind.css
 
 # generate CSS
 bin/rails tailwindcss:build[verbose]