Avoid polluting Object with admin's tailwind rake task helper methods

Methods defined within the `namespace` block of a rake task are
defined on `Object` and are thus available everywhere. We fix it by
extracting them to a module.

We're also renaming the `#compile_file` method to
`#compile_to_tempfile`.

admin/lib/solidus_admin/tailwindcss.rb

@@ -0,0 +1,61 @@
+# frozen_string_literal: true
+
+require "tailwindcss-rails"
+
+module SolidusAdmin
+  # @api private
+  module Tailwindcss
+    module_function
+
+    def run(args = "")
+      config_file = compile_to_tempfile(
+        [config_app_path, config_engine_path].find(&:exist?),
+        "tailwind.config.js"
+      )
+      stylesheet_file = compile_to_tempfile(
+        [stylesheet_app_path, stylesheet_engine_path].find(&:exist?),
+        "application.tailwind.css"
+      )
+
+      system "#{::Tailwindcss::Engine.root.join("exe/tailwindcss")} \
+         -i #{stylesheet_file.path} \
+         -o #{Rails.root.join("app/assets/builds/solidus_admin/tailwind.css")} \
+         -c #{config_file.path} \
+         #{args}"
+    ensure
+      config_file&.close && config_file&.unlink
+      stylesheet_file&.close && stylesheet_file&.unlink
+    end
+
+    def config_app_path
+      Rails.root.join("config", "solidus_admin", "tailwind.config.js.erb")
+    end
+
+    def config_engine_path
+      SolidusAdmin::Engine.root.join("config", "solidus_admin", "tailwind.config.js.erb")
+    end
+
+    def stylesheet_app_path
+      Rails.root.join("app", "assets", "stylesheets", "solidus_admin", "application.tailwind.css.erb")
+    end
+
+    def stylesheet_engine_path
+      SolidusAdmin::Engine.root.join("app", "assets", "stylesheets", "solidus_admin", "application.tailwind.css.erb")
+    end
+
+    def compile_to_tempfile(path, name)
+      Tempfile.new(name).tap do |file|
+        path
+          .then { |path| File.read(path) }
+          .then { |content| ERB.new(content) }
+          .then { |erb| erb.result }
+          .then { |compiled_content| file.write(compiled_content) && file.rewind }
+      end
+    end
+
+    def copy_file(src, dst)
+      FileUtils.mkdir_p(File.dirname(dst))
+      FileUtils.cp(src, dst)
+    end
+  end
+end

admin/lib/tasks/tailwindcss.rake

@@ -1,65 +1,14 @@
 namespace :solidus_admin do
   namespace :tailwindcss do
-    require "tailwindcss-rails"
+    require "solidus_admin/tailwindcss"
 
-    def config_app_path
-      Rails.root.join("config", "solidus_admin", "tailwind.config.js.erb")
-    end
-
-    def config_engine_path
-      SolidusAdmin::Engine.root.join("config", "solidus_admin", "tailwind.config.js.erb")
-    end
-
-    def stylesheet_app_path
-      Rails.root.join("app", "assets", "stylesheets", "solidus_admin", "application.tailwind.css.erb")
-    end
-
-    def stylesheet_engine_path
-      SolidusAdmin::Engine.root.join("app", "assets", "stylesheets", "solidus_admin", "application.tailwind.css.erb")
-    end
-
-    def compile_file(path, name)
-      Tempfile.new(name).tap do |file|
-        path
-          .then { |path| File.read(path) }
-          .then { |content| ERB.new(content) }
-          .then { |erb| erb.result }
-          .then { |compiled_content| file.write(compiled_content) && file.rewind }
-      end
-    end
-
-    def copy_file(src, dst)
-      FileUtils.mkdir_p(dst.dirname)
-      FileUtils.cp(src, dst)
-    end
-
-    def run(args = "")
-      config_file = compile_file(
-        [config_app_path, config_engine_path].find(&:exist?),
-        "tailwind.config.js"
-      )
-      stylesheet_file = compile_file(
-        [stylesheet_app_path, stylesheet_engine_path].find(&:exist?),
-        "application.tailwind.css"
-      )
-
-      system "#{Tailwindcss::Engine.root.join("exe/tailwindcss")} \
-         -i #{stylesheet_file.path} \
-         -o #{Rails.root.join("app/assets/builds/solidus_admin/tailwind.css")} \
-         -c #{config_file.path} \
-         #{args}"
-    ensure
-      config_file&.close && config_file&.unlink
-      stylesheet_file&.close && stylesheet_file&.unlink
-    end
-
-    desc "Build Solidus Admin's TailwindCSS"
+    desc "Build Solidus Admin's Tailwind's css"
     task build: :environment do
-      run
+      SolidusAdmin::Tailwindcss.run
     end
 
     desc <<~DESC
-      Watch and build Solidus Admin's Tailwind CSS on file changes
+      Watch and build Solidus Admin's Tailwind css on file changes
 
       It needs to be re-run whenever:
 
@@ -70,25 +19,31 @@ namespace :solidus_admin do
       - The override files are updated
     DESC
     task watch: :environment do
-      run("-w")
+      SolidusAdmin::Tailwindcss.run("-w")
     end
 
     desc <<~DESC
-      Override Solidus Admin's TailwindCSS configuration
+      Override Solidus Admin's Tailwindcss configuration
 
       It copies the config file from the engine to the app, so it can be customized.
     DESC
     task override_config: :environment do
-      copy_file(config_engine_path, config_app_path)
+      SolidusAdmin::Tailwindcss.copy_file(
+        SolidusAdmin::Tailwindcss.config_engine_path,
+        SolidusAdmin::Tailwindcss.config_app_path
+      )
     end
 
     desc <<~DESC
-      Override Solidus Admin's TailwindCSS stylesheet
+      Override Solidus Admin's Tailwind's stylesheet
 
       It copies the stylesheet file from the engine to the app, so it can be customized.
     DESC
     task override_stylesheet: :environment do
-      copy_file(stylesheet_engine_path, stylesheet_app_path)
+      SolidusAdmin::Tailwindcss.copy_file(
+        SolidusAdmin::Tailwindcss.stylesheet_engine_path,
+        SolidusAdmin::Tailwindcss.stylesheet_app_path
+      )
     end
   end
 end