Add startup banner with Ruby logo, version info, and rotating tips

Display a 3-line startup banner when IRB is launched via the CLI
executable. The banner shows a small braille Ruby logo alongside
the IRB/Ruby version, a randomly selected usage tip, and the
current working directory.

The banner is gated on ap_path matching "irb" so it only appears
for CLI usage, not binding.irb or embedded IRB. Users can disable
it with IRB.conf[:SHOW_BANNER] = false in their .irbrc.

Author: st0012

lib/irb.rb

@@ -21,6 +21,7 @@
 
 require_relative "irb/version"
 require_relative "irb/easter-egg"
+require_relative "irb/startup_message"
 require_relative "irb/debug"
 require_relative "irb/pager"
 
@@ -50,7 +51,13 @@ def start(ap_path = nil)
         irb = Irb.new(nil, @CONF[:SCRIPT])
       else
         irb = Irb.new
+
+        # Only display the banner in the irb executable
+        if @CONF[:SHOW_BANNER] && ap_path&.end_with?("exe/irb")
+          StartupMessage.display
+        end
       end
+
       irb.run(@CONF)
     end
 

lib/irb/init.rb

@@ -87,6 +87,7 @@ def IRB.init_config(ap_path)
     @CONF[:IGNORE_SIGINT] = true
     @CONF[:IGNORE_EOF] = false
     @CONF[:USE_PAGER] = true
+    @CONF[:SHOW_BANNER] = true
     @CONF[:EXTRA_DOC_DIRS] = []
     @CONF[:ECHO] = nil
     @CONF[:ECHO_ON_ASSIGNMENT] = nil

lib/irb/ruby_logo.aa

@@ -116,3 +116,7 @@ TYPE: UNICODE
 ⢻⣾⡇  ⠘⣷  ⣼⠃      ⠘⣷⣠⣴⠟⠋          ⠙⢷⣄⢸⣿
  ⠻⣧⡀  ⠘⣧⣰⡏    ⢀⣠⣤⠶⠛⠉⠛⠛⠛⠛⠛⠛⠻⢶⣶⣶⣶⣶⣶⣤⣤⣽⣿⣿
   ⠈⠛⠷⢦⣤⣽⣿⣥⣤⣶⣶⡿⠿⠿⠶⠶⠶⠶⠾⠛⠛⠛⠛⠛⠛⠛⠋⠉⠉⠉⠉⠉⠉⠁
+TYPE: UNICODE_SMALL
+⢀⡴⠊⢉⡟⢟
+⣎⣀⣴⡋⡟⣻
+⣟⣼⣱⣽⣟⣾

lib/irb/startup_message.rb

@@ -0,0 +1,83 @@
+# frozen_string_literal: true
+
+require_relative "color"
+require_relative "version"
+
+module IRB
+  module StartupMessage
+    TIPS = [
+      'Type "help" for commands, "help <cmd>" for details',
+      '"show_doc method" to view documentation',
+      '"ls [object]" to see methods and properties',
+      '"ls [object] -g pattern" to filter methods and properties',
+      '"edit method" to open the method\'s source in editor',
+      '"cd object" to navigate into an object',
+      '"show_source method" to view source code',
+      '"copy expr" to copy the output to clipboard',
+      '"debug" to start integration with the "debug" gem',
+      '"history -g pattern" to search history',
+    ].freeze
+
+    class << self
+      def display
+        logo_lines = load_logo
+        info_lines = build_info_lines
+
+        output = if logo_lines
+          combine_logo_and_info(logo_lines, info_lines)
+        else
+          info_lines.join("\n")
+        end
+
+        # Add a blank line to not immediately touch warning messages
+        puts
+        puts output
+        puts
+      end
+
+      private
+
+      def load_logo
+        encoding = STDOUT.external_encoding || Encoding.default_external
+        return nil unless encoding == Encoding::UTF_8
+
+        logo = IRB.send(:easter_egg_logo, :unicode_small)
+        return nil unless logo
+
+        logo.chomp.lines.map(&:chomp)
+      end
+
+      def build_info_lines
+        version_line = "#{Color.colorize('IRB', [:BOLD])} v#{VERSION} \u2014 Ruby #{RUBY_VERSION}"
+        tip_line = colorize_tip(TIPS.sample)
+        dir_line = Color.colorize(short_pwd, [:CYAN])
+
+        [version_line, tip_line, dir_line]
+      end
+
+      def colorize_tip(tip)
+        tip.gsub(/"[^"]*"/) { |match| Color.colorize(match, [:YELLOW]) }
+      end
+
+      def combine_logo_and_info(logo_lines, info_lines)
+        max_lines = [logo_lines.size, info_lines.size].max
+        lines = max_lines.times.map do |i|
+          logo_part = logo_lines[i] || ""
+          info_part = info_lines[i] || ""
+          colored_logo = Color.colorize(logo_part, [:RED, :BOLD])
+          "#{colored_logo}  #{info_part}"
+        end
+        lines.join("\n")
+      end
+
+      def short_pwd
+        dir = Dir.pwd
+        home = ENV['HOME']
+        if home && (dir == home || dir.start_with?("#{home}/"))
+          dir = "~#{dir[home.size..]}"
+        end
+        dir
+      end
+    end
+  end
+end

test/irb/helper.rb

@@ -166,7 +166,7 @@ def run_ruby_file(timeout: TIMEOUT_SEC, via_irb: false, &block)
       @envs["XDG_CONFIG_HOME"] ||= tmp_dir
       @envs["IRBRC"] = nil unless @envs.key?("IRBRC")
 
-      envs_for_spawn = @envs.merge('TERM' => 'dumb', 'TEST_IRB_FORCE_INTERACTIVE' => 'true')
+      envs_for_spawn = {'TERM' => 'dumb', 'TEST_IRB_FORCE_INTERACTIVE' => 'true'}.merge(@envs)
 
       PTY.spawn(envs_for_spawn, *cmd) do |read, write, pid|
         Timeout.timeout(timeout) do

test/irb/test_startup_message.rb

@@ -0,0 +1,71 @@
+# frozen_string_literal: true
+
+require "irb"
+
+require_relative "helper"
+
+module TestIRB
+  class StartupMessageTest < TestCase
+    def test_display_includes_version_info
+      output, = capture_output { IRB::StartupMessage.display }
+
+      assert_match(/IRB/, output)
+      assert_match(/v#{Regexp.escape(IRB::VERSION)}/, output)
+      assert_match(/Ruby #{Regexp.escape(RUBY_VERSION)}/, output)
+    end
+
+    def test_display_includes_a_tip
+      output, = capture_output { IRB::StartupMessage.display }
+
+      # Strip ANSI codes for comparison since tips have colorized quoted parts
+      plain = output.gsub(/\e\[\d+m/, "")
+      assert(
+        IRB::StartupMessage::TIPS.any? { |tip| plain.include?(tip) },
+        "Expected output to include one of the tips"
+      )
+    end
+
+    def test_display_includes_working_directory
+      output, = capture_output { IRB::StartupMessage.display }
+
+      assert_match(/#{Regexp.escape(File.basename(Dir.pwd))}/, output)
+    end
+
+    def test_short_pwd_replaces_home_with_tilde
+      Dir.mktmpdir do |tmpdir|
+        tmpdir = File.realpath(tmpdir)
+        original_home = ENV['HOME']
+        original_dir = Dir.pwd
+        ENV['HOME'] = tmpdir
+        Dir.chdir(tmpdir)
+
+        result = IRB::StartupMessage.send(:short_pwd)
+        assert_equal "~", result
+
+        subdir = File.join(tmpdir, "projects")
+        Dir.mkdir(subdir)
+        Dir.chdir(subdir)
+
+        result = IRB::StartupMessage.send(:short_pwd)
+        assert_equal "~/projects", result
+      ensure
+        ENV['HOME'] = original_home
+        Dir.chdir(original_dir)
+      end
+    end
+  end
+
+  class StartupMessageIntegrationTest < IntegrationTestCase
+    def test_banner_does_not_appear_on_binding_irb
+      write_ruby <<~'RUBY'
+        binding.irb
+      RUBY
+
+      output = run_ruby_file do
+        type "exit"
+      end
+
+      assert_not_match(/v#{Regexp.escape(IRB::VERSION)}/, output)
+    end
+  end
+end

test/irb/yamatanooroti/test_rendering.rb

@@ -26,6 +26,7 @@ def setup
     @irbrc_backup = ENV['IRBRC']
     @irbrc_file = ENV['IRBRC'] = File.join(@tmpdir, 'temporaty_irbrc')
     File.unlink(@irbrc_file) if File.exist?(@irbrc_file)
+    File.write(@irbrc_file, "IRB.conf[:SHOW_BANNER] = false\n")
     ENV['HOME'] = File.join(@tmpdir, 'home')
     ENV['XDG_CONFIG_HOME'] = File.join(@tmpdir, 'xdg_config_home')
   end
@@ -520,6 +521,7 @@ def test_debug_integration_doesnt_hint_debugger_commands_in_nomultiline_mode
 
   def write_irbrc(content)
     File.open(@irbrc_file, 'w') do |f|
+      f.write "IRB.conf[:SHOW_BANNER] = false\n"
       f.write content
     end
   end