commands: Deduplicate command print logic

Library/Homebrew/cmd/commands.rb

@@ -31,23 +31,18 @@ module Homebrew
       return
     end
 
-    ohai "Built-in commands", Formatter.columns(Commands.internal_commands)
-    puts
-    ohai "Built-in developer commands", Formatter.columns(Commands.internal_developer_commands)
-
-    external_commands = Commands.external_commands
-    if external_commands.present?
-      puts
-      ohai "External commands", Formatter.columns(external_commands)
-    end
-
-    puts
-    ohai "Cask commands", Formatter.columns(Commands.cask_internal_commands)
-
-    cask_external_commands = Commands.cask_external_commands
-    if cask_external_commands.present?
-      puts
-      ohai "External cask commands", Formatter.columns(cask_external_commands)
+    [["Built-in commands", -> { Commands.internal_commands }],
+     ["Built-in developer commands", -> { Commands.internal_developer_commands }],
+     ["External commands", -> { Commands.external_commands }],
+     ["Cask commands", -> { Commands.cask_internal_commands }],
+     ["External cask commands", -> { Commands.cask_external_commands }]]
+      .each_with_index do |title_and_proc, index|
+      title, proc = title_and_proc
+      cmds = proc.call
+      if cmds.present?
+        puts unless index.zero?
+        ohai title, Formatter.columns(cmds)
+      end
     end
   end
 end

Library/Homebrew/commands.rb

@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-require 'cask/cmd'
+require "cask/cmd"
 
 module Commands
   module_function
@@ -160,10 +160,7 @@ module Commands
   end
 
   def cask_external_commands
-    tap_cmd_directories = Tap.cmd_directories
-    path = PATH.new(tap_cmd_directories, ENV["HOMEBREW_PATH"])
-
-    path.flat_map do |search_path|
+    PATH.new(Tap.cmd_directories, ENV["HOMEBREW_PATH"]).flat_map do |search_path|
       find_commands(search_path).map do |possible_command|
         p = possible_command.to_path
         command_name = p.match(/brewcask-(.*)\.rb/) { |data| data[1].delete_suffix(".rb") }