DEV: Use fewer threads when watching for SCSS changes (#12393)

lib/stylesheet/watcher.rb

@@ -27,24 +27,20 @@ module Stylesheet
     end
 
     def start
-
       Thread.new do
         begin
           while true
             worker_loop
           end
         rescue => e
-          STDERR.puts "CSS change notifier crashed #{e}"
+          STDERR.puts "CSS change notifier crashed \n#{e}"
           start
         end
       end
 
-      root = Rails.root.to_s
-
-      listener_opts = { ignore: /xxxx/ }
+      listener_opts = { ignore: /xxxx/, only: /\.(css|scss)$/ }
       listener_opts[:force_polling] = true if ENV['FORCE_POLLING']
 
-      @paths.each do |watch|
       Thread.new do
         begin
           plugins_paths = Dir.glob("#{Rails.root}/plugins/*").map do |file|
@@ -55,7 +51,7 @@ module Stylesheet
             end
           end.compact
 
-            listener = Listen.to("#{root}/#{watch}", listener_opts) do |modified, added, _|
+          listener = Listen.to(*@paths, listener_opts) do |modified, added, _|
             paths = [modified, added].flatten
             paths.compact!
             paths.map! do |long|
@@ -83,13 +79,12 @@ module Stylesheet
             process_change(paths)
           end
         rescue => e
-            STDERR.puts "Failed to listen for CSS changes at: #{watch}\n#{e}"
+          STDERR.puts "Failed to listen for CSS changes: \n#{e}"
         end
         listener.start
         sleep
       end
     end
-    end
 
     def core_assets_refresh(target)
       targets = target ? [target] : ["desktop", "mobile", "admin"]
@@ -138,11 +133,9 @@ module Stylesheet
 
     def process_change(paths)
       paths.each do |path|
-        if path[:basename] =~ /\.(css|scss)$/
         @queue.push path
       end
     end
-    end
 
     def active_themes
       @active_themes ||= Theme.user_selectable.pluck(:id)