[Bug Fix] Install tw-animate-css for importmap

gem/lib/generators/ruby_ui/install/templates/tailwind.css.erb

@@ -1,7 +1,7 @@
 @import "tailwindcss";
 
 <% if using_importmap? %>
-@import "../../../vendor/javascript/tw-animate-css.js";
+@import "../../../vendor/javascript/tw-animate-css.css";
 <% else %>
 @import "tw-animate-css";
 <% end %>

gem/lib/generators/ruby_ui/javascript_utils.rb

@@ -1,6 +1,8 @@
 module RubyUI
   module Generators
     module JavascriptUtils
+      TW_ANIMATE_CSS_VERSION = "1.4.0"
+
       def install_js_package(package)
         if using_importmap?
           pin_with_importmap(package)
@@ -21,6 +23,8 @@ def pin_with_importmap(package)
         case package
         when "motion"
           pin_motion
+        when "tw-animate-css"
+          pin_tw_animate_css
         when "tippy.js"
           pin_tippy_js
         else
@@ -29,23 +33,34 @@ def pin_with_importmap(package)
       end
 
       def using_importmap?
-        File.exist?(Rails.root.join("config/importmap.rb")) && File.exist?(Rails.root.join("bin/importmap"))
+        File.exist?(rails_root.join("config/importmap.rb")) && File.exist?(rails_root.join("bin/importmap"))
       end
 
-      def using_bun? = File.exist?(Rails.root.join("bun.lock"))
+      def using_bun? = File.exist?(rails_root.join("bun.lock"))
+
+      def using_npm? = File.exist?(rails_root.join("package-lock.json"))
 
-      def using_npm? = File.exist?(Rails.root.join("package-lock.json"))
+      def using_pnpm? = File.exist?(rails_root.join("pnpm-lock.yaml"))
 
-      def using_pnpm? = File.exist?(Rails.root.join("pnpm-lock.yaml"))
+      def using_yarn? = File.exist?(rails_root.join("yarn.lock"))
 
-      def using_yarn? = File.exist?(Rails.root.join("yarn.lock"))
+      def pin_tw_animate_css
+        say <<~TEXT
+          WARNING: Installing tw-animate-css as a CSS asset because Importmap cannot pin CSS-only package exports.
+        TEXT
+
+        empty_directory rails_root.join("vendor/javascript")
+        # CDN serves "tw-animate.css"; we save as "tw-animate-css.css" to match package name. Do not "correct" the URL.
+        get "https://cdn.jsdelivr.net/npm/tw-animate-css@#{TW_ANIMATE_CSS_VERSION}/dist/tw-animate.css",
+          rails_root.join("vendor/javascript/tw-animate-css.css")
+      end
 
       def pin_motion
         say <<~TEXT
           WARNING: Installing motion from CDN because `bin/importmap pin motion` doesn't download the correct file.
         TEXT
 
-        inject_into_file Rails.root.join("config/importmap.rb"), <<~RUBY
+        inject_into_file rails_root.join("config/importmap.rb"), <<~RUBY
           pin "motion", to: "https://cdn.jsdelivr.net/npm/motion@11.11.17/+esm"\n
         RUBY
       end
@@ -55,11 +70,13 @@ def pin_tippy_js
           WARNING: Installing tippy.js from CDN because `bin/importmap pin tippy.js` doesn't download the correct file.
         TEXT
 
-        inject_into_file Rails.root.join("config/importmap.rb"), <<~RUBY
+        inject_into_file rails_root.join("config/importmap.rb"), <<~RUBY
           pin "tippy.js", to: "https://cdn.jsdelivr.net/npm/tippy.js@6.3.7/+esm"
           pin "@popperjs/core", to: "https://cdn.jsdelivr.net/npm/@popperjs/core@2.11.8/+esm"\n
         RUBY
       end
+
+      def rails_root = Rails.root
     end
   end
 end

gem/test/generators/javascript_utils_test.rb

@@ -0,0 +1,45 @@
+# frozen_string_literal: true
+
+require "test_helper"
+require "fileutils"
+require "pathname"
+require "tmpdir"
+require_relative "../../lib/generators/ruby_ui/javascript_utils"
+
+class JavascriptUtilsTest < Minitest::Test
+  class FakeInstaller
+    include RubyUI::Generators::JavascriptUtils
+
+    attr_reader :download_source, :download_destination
+
+    def initialize(root)
+      @root = Pathname.new(root)
+    end
+
+    def say(*) = nil
+
+    def empty_directory(path)
+      FileUtils.mkdir_p(path)
+    end
+
+    def get(source, destination)
+      @download_source = source
+      @download_destination = destination
+      FileUtils.touch(destination)
+    end
+
+    def rails_root = @root
+  end
+
+  def test_tw_animate_css_is_downloaded_as_css_asset_for_importmap
+    Dir.mktmpdir do |root|
+      installer = FakeInstaller.new(root)
+
+      installer.pin_with_importmap("tw-animate-css")
+
+      assert_equal "https://cdn.jsdelivr.net/npm/tw-animate-css@1.4.0/dist/tw-animate.css", installer.download_source
+      assert_equal Pathname.new(root).join("vendor/javascript/tw-animate-css.css"), installer.download_destination
+      assert File.exist?(installer.download_destination)
+    end
+  end
+end