caveats: recommend brew services for plists.

It simplifies the number of commands and it's now an officially
supported command again.

Library/Homebrew/caveats.rb

@@ -162,7 +162,6 @@ class Caveats
       else
         File.basename Dir["#{keg}/*.plist"].first
       end
-      plist_link = "#{destination}/#{plist_filename}"
       plist_domain = f.plist_path.basename(".plist")
       destination_path = Pathname.new File.expand_path destination
       plist_path = destination_path/plist_filename
@@ -173,44 +172,31 @@ class Caveats
       # https://github.com/Homebrew/homebrew/issues/33815
       if !plist_path.file? || !plist_path.symlink?
         if f.plist_startup
-          s << "To have launchd start #{f.full_name} at startup:"
-          s << "  sudo mkdir -p #{destination}" unless destination_path.directory?
-          s << "  sudo cp -fv #{f.opt_prefix}/*.plist #{destination}"
-          s << "  sudo chown root #{plist_link}"
+          s << "To have launchd start #{f.full_name} now and restart at startup:"
+          s << "  sudo brew services start #{f.full_name}"
         else
-          s << "To have launchd start #{f.full_name} at login:"
-          s << "  mkdir -p #{destination}" unless destination_path.directory?
-          s << "  ln -sfv #{f.opt_prefix}/*.plist #{destination}"
-        end
-        s << "Then to load #{f.full_name} now:"
-        if f.plist_startup
-          s << "  sudo launchctl load #{plist_link}"
-        else
-          s << "  launchctl load #{plist_link}"
+          s << "To have launchd start #{f.full_name} now and restart at login:"
+          s << "  brew services start #{f.full_name}"
         end
       # For startup plists, we cannot tell whether it's running on launchd,
       # as it requires for `sudo launchctl list` to get real result.
       elsif f.plist_startup
-        s << "To reload #{f.full_name} after an upgrade:"
-        s << "  sudo launchctl unload #{plist_link}"
-        s << "  sudo cp -fv #{f.opt_prefix}/*.plist #{destination}"
-        s << "  sudo chown root #{plist_link}"
-        s << "  sudo launchctl load #{plist_link}"
+        s << "To restart #{f.full_name} after an upgrade:"
+        s << "  sudo brew services restart #{f.full_name}"
       elsif Kernel.system "/bin/launchctl list #{plist_domain} &>/dev/null"
-        s << "To reload #{f.full_name} after an upgrade:"
-        s << "  launchctl unload #{plist_link}"
-        s << "  launchctl load #{plist_link}"
+        s << "To restart #{f.full_name} after an upgrade:"
+        s << "  brew services restart #{f.full_name}"
       else
-        s << "To load #{f.full_name}:"
-        s << "  launchctl load #{plist_link}"
+        s << "To start #{f.full_name}:"
+        s << "  brew services start #{f.full_name}"
       end
 
       if f.plist_manual
-        s << "Or, if you don't want/need launchctl, you can just run:"
+        s << "Or, if you don't want/need a background service you can just run:"
         s << "  #{f.plist_manual}"
       end
 
-      s << "" << "WARNING: launchctl will fail when run under tmux." if ENV["TMUX"]
+      s << "" << "WARNING: brew services will fail when run under tmux." if ENV["TMUX"]
     end
     s.join("\n") + "\n" unless s.empty?
   end