[ruby/irb] Easter egg for autocomplete mode

(https://github.com/ruby/irb/pull/737)

* Show easter-egg inside document dialog in autocomplete mode

* Show more easter_egg(dancing or logo) when Alt+d is pressed in autocomplete mode

https://github.com/ruby/irb/commit/a8e5cc7354

lib/irb/easter-egg.rb

@@ -98,15 +98,21 @@ module IRB
       end
     end
 
+    private def easter_egg_logo(type)
+      @easter_egg_logos ||= File.read(File.join(__dir__, 'ruby_logo.aa'), encoding: 'UTF-8:UTF-8')
+        .split(/TYPE: ([A-Z]+)\n/)[1..]
+        .each_slice(2)
+        .to_h
+      @easter_egg_logos[type.to_s.upcase]
+    end
+
     private def easter_egg(type = nil)
       type ||= [:logo, :dancing].sample
       case type
       when :logo
-        File.open(File.join(__dir__, 'ruby_logo.aa')) do |f|
-          require "rdoc"
-          RDoc::RI::Driver.new.page do |io|
-            IO.copy_stream(f, io)
-          end
+        require "rdoc"
+        RDoc::RI::Driver.new.page do |io|
+          io.write easter_egg_logo(:large)
         end
       when :dancing
         begin

lib/irb/input-method.rb

@@ -303,15 +303,20 @@ module IRB
         return nil if result.nil? or pointer.nil? or pointer < 0
 
         name = doc_namespace.call(result[pointer])
+        show_easter_egg = name&.match?(/\ARubyVM/) && !ENV['RUBY_YES_I_AM_NOT_A_NORMAL_USER']
 
         options = {}
         options[:extra_doc_dirs] = IRB.conf[:EXTRA_DOC_DIRS] unless IRB.conf[:EXTRA_DOC_DIRS].empty?
         driver = RDoc::RI::Driver.new(options)
 
         if key.match?(dialog.name)
-          begin
-            driver.display_names([name])
-          rescue RDoc::RI::Driver::NotFoundError
+          if show_easter_egg
+            IRB.__send__(:easter_egg)
+          else
+            begin
+              driver.display_names([name])
+            rescue RDoc::RI::Driver::NotFoundError
+            end
           end
         end
 
@@ -374,8 +379,15 @@ module IRB
         formatter.width = width
         dialog.trap_key = alt_d
         mod_key = RUBY_PLATFORM.match?(/darwin/) ? "Option" : "Alt"
-        message = "Press #{mod_key}+d to read the full document"
-        contents = [message] + doc.accept(formatter).split("\n")
+        if show_easter_egg
+          type = STDOUT.external_encoding == Encoding::UTF_8 ? :unicode : :ascii
+          contents = IRB.send(:easter_egg_logo, type).split("\n")
+          message = "Press #{mod_key}+d to see more"
+          contents[0][0, message.size] = message
+        else
+          message = "Press #{mod_key}+d to read the full document"
+          contents = [message] + doc.accept(formatter).split("\n")
+        end
         contents = contents.take(preferred_dialog_height)
 
         y = cursor_pos_to_render.y

lib/irb/ruby_logo.aa

@@ -1,3 +1,4 @@
+TYPE: LARGE
 
                                              -+smJYYN?mm-
                                    HB"BBYT            TQg  NggT
@@ -35,3 +36,45 @@
     m7       NW H            N                        HSVO1z=?11-
       NgTH    bB        kH   WBHWWHBHWmQgg&gggggNNN
            NNggggggNN
+TYPE: ASCII
+                  ,,,;;;;''''';;;'';,
+              ,,;''     ';;,;;;      ',
+           ,,''          ;;'';'''';;;;;;
+         ,;'             ;;   ',,      ;
+       ,;'              ,;'     ';,    ;
+      ;'               ,;;         ',,,;
+    ,'                ,;;,,,,,,,,,,,;;;;
+   ;'                ;;';;;;         ,;;
+  ;'               ,;'  ;; '',,     ,;;;
+ ;;              ,;'     ;    '';, ,; ;'
+;;            ,;;'       ;;       ;; ;;
+;;,        ,,;;'          ;      ;'; ;;
+;';;,,,,;;;;;;;,,,        ;;   ,'  ; ;;
+; ;;'''    ,;';  ''';,,,   ; ,;'   ;;;;
+;;;;,      ;  ';       ''';;;'     ';;;
+;'; ;,    ;'   ';        ,;' ',     ;;;
+;;;  ;   ,;     ';    ,,'      ',,  ;;
+;;;  ';  ;'      ';,,''          ';,;;
+ ';   ';,;     ,,;''''''''';;;;;;,,;;;
+   ';,,;;,,;;;;;;;;;;''''''''''''''
+TYPE: UNICODE
+                  ⣀⣤⣴⣾⣿⣿⣿⡛⠛⠛⠛⠛⣻⣿⠿⠛⠛⠶⣤⡀
+              ⣀⣴⠾⠛⠉⠁    ⠙⣿⣶⣤⣶⣟⣉     ⠈⠻⣦
+           ⣀⣴⠟⠋          ⢸⣿⠟⠻⣯⡙⠛⠛⠛⠶⠶⠶⢶⣽⣇
+         ⣠⡾⠋⠁            ⣾⡿  ⠈⠛⢦⣄      ⣿
+       ⣠⡾⠋              ⣰⣿⠃     ⠙⠷⣤⡀   ⣿
+     ⢀⡾⠋               ⣰⣿⡏        ⠈⠻⣦⣄⢠⣿
+    ⣰⠟⠁               ⣴⣿⣿⣁⣀⣠⣤⣤⣤⣤⣤⣤⣤⣴⠶⠿⣿⡏
+   ⣼⠏               ⢀⣾⣿⠟⣿⠿⣯⣍⠁        ⣰⣿⡇
+ ⢀⣼⠋              ⢀⣴⣿⠟⠁ ⢸⡇ ⠙⠻⢦⣄⡀    ⢠⡿⣿⡇
+⢀⣾⡏             ⢀⣴⣿⠟⠁    ⣿    ⠉⠻⢶⣄⡀⣰⡟ ⣿⠃
+⣾⣿⠁           ⣠⣶⡿⠋⠁      ⢹⡇      ⠈⣿⡏ ⢸⣿
+⣿⣿⡆       ⢀⣠⣴⣿⡿⠋         ⠈⣿     ⢀⡾⠋⣿ ⢸⣿
+⣿⠸⣿⣶⣤⣤⣤⣤⣶⣾⠿⠿⣿⣿⠶⣤⣤⣀⡀       ⢹⡇   ⣴⠟⠁ ⣿⡀⢸⣿
+⣿⢀⣿⣟⠛⠋⠉⠁   ⢰⡟⠹⣧ ⠈⠉⠛⠻⠶⢦⣤⣀⡀ ⠈⣿ ⣠⡾⠃   ⢸⡇⢸⡇
+⣿⣾⣿⢿⡄      ⣿⠁ ⠘⣧       ⠉⠙⠛⠷⣿⣿⡋     ⠸⣇⣸⡇
+⣿⠃⣿⠈⢿⡄    ⣸⠇   ⠘⣧       ⢀⣤⠾⠋⠈⠻⣦⡀    ⣿⣿⡇
+⣿⢸⡏ ⠈⣷⡀  ⢠⡿     ⠘⣧⡀   ⣠⡴⠟⠁    ⠈⠻⣦⣀  ⢿⣿⠁
+⢻⣾⡇  ⠘⣷  ⣼⠃      ⠘⣷⣠⣴⠟⠋          ⠙⢷⣄⢸⣿
+ ⠻⣧⡀  ⠘⣧⣰⡏    ⢀⣠⣤⠶⠛⠉⠛⠛⠛⠛⠛⠛⠻⢶⣶⣶⣶⣶⣶⣤⣤⣽⣿⣿
+  ⠈⠛⠷⢦⣤⣽⣿⣥⣤⣶⣶⡿⠿⠿⠶⠶⠶⠶⠾⠛⠛⠛⠛⠛⠛⠛⠋⠉⠉⠉⠉⠉⠉⠁