[ruby/irb] Add irb_info command

https://github.com/ruby/irb/commit/a6fe58e916

lib/irb/cmd/info.rb

@@ -0,0 +1,25 @@
+# frozen_string_literal: false
+
+require_relative "nop"
+
+# :stopdoc:
+module IRB
+  module ExtendCommand
+    class Info < Nop
+      def execute
+        Class.new {
+          def inspect
+            <<~EOM.chomp
+              Ruby version: #{RUBY_VERSION}
+              IRB version: #{IRB.version}
+              InputMethod: #{IRB.CurrentContext.io.inspect}
+              .irbrc path: #{IRB.rc_file}
+            EOM
+          end
+          alias_method :to_s, :inspect
+        }.new
+      end
+    end
+  end
+end
+# :startdoc:

lib/irb/extend-command.rb

@@ -121,6 +121,10 @@ module IRB # :nodoc:
         [:help, NO_OVERRIDE],
       ],
 
+      [
+        :irb_info, :Info, "irb/cmd/info"
+      ],
+
     ]
 
     # Installs the default irb commands:

lib/irb/input-method.rb

@@ -43,6 +43,11 @@ module IRB
     def readable_after_eof?
       false
     end
+
+    # For debug message
+    def inspect
+      'Abstract InputMethod'
+    end
   end
 
   class StdioInputMethod < InputMethod
@@ -93,6 +98,11 @@ module IRB
     def encoding
       @stdin.external_encoding
     end
+
+    # For debug message
+    def inspect
+      'StdioInputMethod'
+    end
   end
 
   # Use a File for IO with irb, see InputMethod
@@ -125,6 +135,11 @@ module IRB
     def encoding
       @io.external_encoding
     end
+
+    # For debug message
+    def inspect
+      'FileInputMethod'
+    end
   end
 
   begin
@@ -202,6 +217,13 @@ module IRB
       end
       Readline.completion_append_character = nil
       Readline.completion_proc = IRB::InputCompletor::CompletionProc
+
+      # For debug message
+      def inspect
+        inputrc_path = File.expand_path(ENV['INPUTRC'] || '~/.inputrc')
+        readline_impl = (defined?(Reline) && Readline == Reline) ? 'Reline' : 'ext/readline'
+        "ReadlineInputMethod with #{readline_impl} #{Readline::VERSION} and #{inputrc_path}"
+      end
     end
   rescue LoadError
   end
@@ -297,5 +319,16 @@ module IRB
     def encoding
       @stdin.external_encoding
     end
+
+    # For debug message
+    def inspect
+      config = Reline::Config.new
+      if config.respond_to?(:inputrc_path)
+        inputrc_path = config.inputrc_path
+      else
+        inputrc_path = File.expand_path(ENV['INPUTRC'] || '~/.inputrc')
+      end
+      "ReidlineInputMethod with Reline #{Reline::VERSION} and #{inputrc_path}"
+    end
   end
 end

test/irb/test_cmd.rb

@@ -0,0 +1,64 @@
+# frozen_string_literal: false
+require "test/unit"
+require "irb"
+require "irb/extend-command"
+
+module TestIRB
+  class ExtendCommand < Test::Unit::TestCase
+    def setup
+      @pwd = Dir.pwd
+      @tmpdir = File.join(Dir.tmpdir, "test_reline_config_#{$$}")
+      begin
+        Dir.mkdir(@tmpdir)
+      rescue Errno::EEXIST
+        FileUtils.rm_rf(@tmpdir)
+        Dir.mkdir(@tmpdir)
+      end
+      Dir.chdir(@tmpdir)
+      @home_backup = ENV["HOME"]
+      ENV["HOME"] = @tmpdir
+    end
+
+    def teardown
+      ENV["HOME"] = @home_backup
+      Dir.chdir(@pwd)
+      FileUtils.rm_rf(@tmpdir)
+    end
+
+    def test_irb_info_multiline
+      FileUtils.touch("#{@tmpdir}/.inputrc")
+      FileUtils.touch("#{@tmpdir}/.irbrc")
+      IRB.setup(__FILE__, argv: [])
+      IRB.conf[:USE_MULTILINE] = true
+      IRB.conf[:USE_SINGLELINE] = false
+      workspace = IRB::WorkSpace.new(self)
+      irb = IRB::Irb.new(workspace)
+      IRB.conf[:MAIN_CONTEXT] = irb.context
+      expected = %r{
+        Ruby\sversion: .+\n
+        IRB\sversion:\sirb .+\n
+        InputMethod:\sReidlineInputMethod\swith\sReline .+ and .+\n
+        \.irbrc\spath: .+
+      }x
+      assert_match expected, irb.context.main.irb_info.to_s
+    end
+
+    def test_irb_info_singleline
+      FileUtils.touch("#{@tmpdir}/.inputrc")
+      FileUtils.touch("#{@tmpdir}/.irbrc")
+      IRB.setup(__FILE__, argv: [])
+      IRB.conf[:USE_MULTILINE] = false
+      IRB.conf[:USE_SINGLELINE] = true
+      workspace = IRB::WorkSpace.new(self)
+      irb = IRB::Irb.new(workspace)
+      IRB.conf[:MAIN_CONTEXT] = irb.context
+      expected = %r{
+        Ruby\sversion: .+\n
+        IRB\sversion:\sirb .+\n
+        InputMethod:\sReadlineInputMethod\swith .+ and .+\n
+        \.irbrc\spath: .+
+      }x
+      assert_match expected, irb.context.main.irb_info.to_s
+    end
+  end
+end