[ruby/reline] Reduce direct references to Reline::IOGate

(ruby/reline#566)

* Avoid referencing IOGate from IOGate classes

The only time those classes being used is when themselves being the IOGate.
So when referencing to IOGate, it's better to use `self` instead.

* Avoid referencing to IOGate from LineEditor directly

* Avoid referencing to IOGate from Core directly

* Reference to Reline.core directly

* Replace Reline::IOGate with Reline.core.io_gate

lib/reline.rb

@@ -83,8 +83,12 @@ def initialize
       @bracketed_paste_finished = false
     end
 
+    def io_gate
+      Reline::IOGate
+    end
+
     def encoding
-      Reline::IOGate.encoding
+      io_gate.encoding
     end
 
     def completion_append_character=(val)
@@ -181,16 +185,16 @@ def dialog_proc(name_sym)
 
     def input=(val)
       raise TypeError unless val.respond_to?(:getc) or val.nil?
-      if val.respond_to?(:getc) && Reline::IOGate.respond_to?(:input=)
-        Reline::IOGate.input = val
+      if val.respond_to?(:getc) && io_gate.respond_to?(:input=)
+        io_gate.input = val
       end
     end
 
     def output=(val)
       raise TypeError unless val.respond_to?(:write) or val.nil?
       @output = val
-      if Reline::IOGate.respond_to?(:output=)
-        Reline::IOGate.output = val
+      if io_gate.respond_to?(:output=)
+        io_gate.output = val
       end
     end
 
@@ -213,7 +217,7 @@ def emacs_editing_mode?
     end
 
     def get_screen_size
-      Reline::IOGate.get_screen_size
+      io_gate.get_screen_size
     end
 
     Reline::DEFAULT_DIALOG_PROC_AUTOCOMPLETE = ->() {
@@ -267,7 +271,7 @@ def get_screen_size
 
     def readmultiline(prompt = '', add_hist = false, &confirm_multiline_termination)
       Reline.update_iogate
-      Reline::IOGate.with_raw_input do
+      io_gate.with_raw_input do
         unless confirm_multiline_termination
           raise ArgumentError.new('#readmultiline needs block to confirm multiline termination')
         end
@@ -300,15 +304,15 @@ def readline(prompt = '', add_hist = false)
 
     private def inner_readline(prompt, add_hist, multiline, &confirm_multiline_termination)
       if ENV['RELINE_STDERR_TTY']
-        if Reline::IOGate.win?
+        if io_gate.win?
           $stderr = File.open(ENV['RELINE_STDERR_TTY'], 'a')
         else
           $stderr.reopen(ENV['RELINE_STDERR_TTY'], 'w')
         end
         $stderr.sync = true
         $stderr.puts "Reline is used by #{Process.pid}"
       end
-      otio = Reline::IOGate.prep
+      otio = io_gate.prep
 
       may_req_ambiguous_char_width
       line_editor.reset(prompt, encoding: encoding)
@@ -335,7 +339,7 @@ def readline(prompt = '', add_hist = false)
       unless config.test_mode
         config.read
         config.reset_default_key_bindings
-        Reline::IOGate.set_default_key_bindings(config)
+        io_gate.set_default_key_bindings(config)
       end
 
       line_editor.rerender
@@ -344,9 +348,9 @@ def readline(prompt = '', add_hist = false)
         line_editor.set_signal_handlers
         prev_pasting_state = false
         loop do
-          prev_pasting_state = Reline::IOGate.in_pasting?
+          prev_pasting_state = io_gate.in_pasting?
           read_io(config.keyseq_timeout) { |inputs|
-            line_editor.set_pasting_state(Reline::IOGate.in_pasting?)
+            line_editor.set_pasting_state(io_gate.in_pasting?)
             inputs.each { |c|
               line_editor.input_key(c)
               line_editor.rerender
@@ -356,29 +360,29 @@ def readline(prompt = '', add_hist = false)
               @bracketed_paste_finished = false
             end
           }
-          if prev_pasting_state == true and not Reline::IOGate.in_pasting? and not line_editor.finished?
+          if prev_pasting_state == true and not io_gate.in_pasting? and not line_editor.finished?
             line_editor.set_pasting_state(false)
             prev_pasting_state = false
             line_editor.rerender_all
           end
           break if line_editor.finished?
         end
-        Reline::IOGate.move_cursor_column(0)
+        io_gate.move_cursor_column(0)
       rescue Errno::EIO
         # Maybe the I/O has been closed.
       rescue StandardError => e
         line_editor.finalize
-        Reline::IOGate.deprep(otio)
+        io_gate.deprep(otio)
         raise e
       rescue Exception
         # Including Interrupt
         line_editor.finalize
-        Reline::IOGate.deprep(otio)
+        io_gate.deprep(otio)
         raise
       end
 
       line_editor.finalize
-      Reline::IOGate.deprep(otio)
+      io_gate.deprep(otio)
     end
 
     # GNU Readline waits for "keyseq-timeout" milliseconds to see if the ESC
@@ -393,7 +397,7 @@ def readline(prompt = '', add_hist = false)
     private def read_io(keyseq_timeout, &block)
       buffer = []
       loop do
-        c = Reline::IOGate.getc
+        c = io_gate.getc
         if c == -1
           result = :unmatched
           @bracketed_paste_finished = true
@@ -433,7 +437,7 @@ def readline(prompt = '', add_hist = false)
       begin
         succ_c = nil
         Timeout.timeout(keyseq_timeout / 1000.0) {
-          succ_c = Reline::IOGate.getc
+          succ_c = io_gate.getc
         }
       rescue Timeout::Error # cancel matching only when first byte
         block.([Reline::Key.new(c, c, false)])
@@ -448,7 +452,7 @@ def readline(prompt = '', add_hist = false)
           end
           return :break
         when :matching
-          Reline::IOGate.ungetc(succ_c)
+          io_gate.ungetc(succ_c)
           return :next
         when :matched
           buffer << succ_c
@@ -465,7 +469,7 @@ def readline(prompt = '', add_hist = false)
       begin
         escaped_c = nil
         Timeout.timeout(keyseq_timeout / 1000.0) {
-          escaped_c = Reline::IOGate.getc
+          escaped_c = io_gate.getc
         }
       rescue Timeout::Error # independent ESC
         block.([Reline::Key.new(c, c, false)])
@@ -488,19 +492,19 @@ def ambiguous_width
     end
 
     private def may_req_ambiguous_char_width
-      @ambiguous_width = 2 if Reline::IOGate == Reline::GeneralIO or !STDOUT.tty?
+      @ambiguous_width = 2 if io_gate == Reline::GeneralIO or !STDOUT.tty?
       return if defined? @ambiguous_width
-      Reline::IOGate.move_cursor_column(0)
+      io_gate.move_cursor_column(0)
       begin
         output.write "\u{25bd}"
       rescue Encoding::UndefinedConversionError
         # LANG=C
         @ambiguous_width = 1
       else
-        @ambiguous_width = Reline::IOGate.cursor_pos.x
+        @ambiguous_width = io_gate.cursor_pos.x
       end
-      Reline::IOGate.move_cursor_column(0)
-      Reline::IOGate.erase_after_cursor
+      io_gate.move_cursor_column(0)
+      io_gate.erase_after_cursor
     end
   end
 
@@ -576,7 +580,7 @@ def self.core
   end
 
   def self.ungetc(c)
-    Reline::IOGate.ungetc(c)
+    core.io_gate.ungetc(c)
   end
 
   def self.line_editor
@@ -588,7 +592,7 @@ def self.update_iogate
 
     # Need to change IOGate when `$stdout.tty?` change from false to true by `$stdout.reopen`
     # Example: rails/spring boot the application in non-tty, then run console in tty.
-    if ENV['TERM'] != 'dumb' && Reline::IOGate == Reline::GeneralIO && $stdout.tty?
+    if ENV['TERM'] != 'dumb' && core.io_gate == Reline::GeneralIO && $stdout.tty?
       require 'reline/ansi'
       remove_const(:IOGate)
       const_set(:IOGate, Reline::ANSI)

lib/reline/ansi.rb

@@ -206,7 +206,7 @@ def self.getc
   end
 
   def self.in_pasting?
-    @@in_bracketed_paste_mode or (not Reline::IOGate.empty_buffer?)
+    @@in_bracketed_paste_mode or (not empty_buffer?)
   end
 
   def self.empty_buffer?

lib/reline/line_editor.rb

@@ -60,6 +60,10 @@ def initialize(config, encoding)
     reset_variables(encoding: encoding)
   end
 
+  def io_gate
+    Reline::IOGate
+  end
+
   def set_pasting_state(in_pasting)
     @in_pasting = in_pasting
   end

test/reline/helper.rb

@@ -29,8 +29,8 @@ def test_mode(ansi: false)
           encoding = Encoding::UTF_8
         end
         Reline::GeneralIO.reset(encoding: encoding) unless ansi
-        send(:core).config.instance_variable_set(:@test_mode, true)
-        send(:core).config.reset
+        core.config.instance_variable_set(:@test_mode, true)
+        core.config.reset
     end
 
     def test_reset

test/reline/test_ansi_with_terminfo.rb

@@ -5,7 +5,7 @@ class Reline::ANSI::TestWithTerminfo < Reline::TestCase
   def setup
     Reline.send(:test_mode, ansi: true)
     @config = Reline::Config.new
-    Reline::IOGate.set_default_key_bindings(@config, allow_terminfo: true)
+    Reline.core.io_gate.set_default_key_bindings(@config, allow_terminfo: true)
   end
 
   def teardown

test/reline/test_ansi_without_terminfo.rb

@@ -5,7 +5,7 @@ class Reline::ANSI::TestWithoutTerminfo < Reline::TestCase
   def setup
     Reline.send(:test_mode, ansi: true)
     @config = Reline::Config.new
-    Reline::IOGate.set_default_key_bindings(@config, allow_terminfo: false)
+    Reline.core.io_gate.set_default_key_bindings(@config, allow_terminfo: false)
   end
 
   def teardown

test/reline/test_config.rb

@@ -85,15 +85,15 @@ def test_string_value_with_parens_and_quotes
 
   def test_encoding_is_ascii
     @config.reset
-    Reline::IOGate.reset(encoding: Encoding::US_ASCII)
+    Reline.core.io_gate.reset(encoding: Encoding::US_ASCII)
     @config = Reline::Config.new
 
     assert_equal true, @config.convert_meta
   end
 
   def test_encoding_is_not_ascii
     @config.reset
-    Reline::IOGate.reset(encoding: Encoding::UTF_8)
+    Reline.core.io_gate.reset(encoding: Encoding::UTF_8)
     @config = Reline::Config.new
 
     assert_equal nil, @config.convert_meta

test/reline/test_history.rb

@@ -297,7 +297,7 @@ def assert_external_string_equal(expected, actual)
   end
 
   def get_default_internal_encoding
-    if encoding = Reline::IOGate.encoding
+    if encoding = Reline.core.encoding
       encoding
     elsif RUBY_PLATFORM =~ /mswin|mingw/
       Encoding.default_internal || Encoding::UTF_8

test/reline/test_key_actor_emacs.rb

@@ -8,7 +8,7 @@ def setup
     @config.autocompletion = false
     Reline::HISTORY.instance_variable_set(:@config, @config)
     Reline::HISTORY.clear
-    @encoding = Reline::IOGate.encoding
+    @encoding = Reline.core.encoding
     @line_editor = Reline::LineEditor.new(@config, @encoding)
     @line_editor.reset(@prompt, encoding: @encoding)
   end
@@ -2167,7 +2167,7 @@ def test_ed_search_next_history_with_empty
 
   # Unicode emoji test
   def test_ed_insert_for_include_zwj_emoji
-    omit "This test is for UTF-8 but the locale is #{Reline::IOGate.encoding}" if Reline::IOGate.encoding != Encoding::UTF_8
+    omit "This test is for UTF-8 but the locale is #{Reline.core.encoding}" if Reline.core.encoding != Encoding::UTF_8
     # U+1F468 U+200D U+1F469 U+200D U+1F467 U+200D U+1F466 is family: man, woman, girl, boy "👨‍👩‍👧‍👦"
     input_keys("\u{1F468}") # U+1F468 is man "👨"
     assert_line("\u{1F468}")
@@ -2213,7 +2213,7 @@ def test_ed_insert_for_include_zwj_emoji
   end
 
   def test_ed_insert_for_include_valiation_selector
-    omit "This test is for UTF-8 but the locale is #{Reline::IOGate.encoding}" if Reline::IOGate.encoding != Encoding::UTF_8
+    omit "This test is for UTF-8 but the locale is #{Reline.core.encoding}" if Reline.core.encoding != Encoding::UTF_8
     # U+0030 U+FE00 is DIGIT ZERO + VARIATION SELECTOR-1 "0︀"
     input_keys("\u0030") # U+0030 is DIGIT ZERO
     assert_line("\u0030")

test/reline/test_key_actor_vi.rb

@@ -8,7 +8,7 @@ def setup
     @config.read_lines(<<~LINES.split(/(?<=\n)/))
       set editing-mode vi
     LINES
-    @encoding = Reline::IOGate.encoding
+    @encoding = Reline.core.encoding
     @line_editor = Reline::LineEditor.new(@config, @encoding)
     @line_editor.reset(@prompt, encoding: @encoding)
   end

test/reline/test_macro.rb

@@ -4,7 +4,7 @@ class Reline::MacroTest < Reline::TestCase
   def setup
     Reline.send(:test_mode)
     @config = Reline::Config.new
-    @encoding = Reline::IOGate.encoding
+    @encoding = Reline.core.encoding
     @line_editor = Reline::LineEditor.new(@config, @encoding)
     @line_editor.instance_variable_set(:@screen_size, [24, 80])
     @output = @line_editor.output = File.open(IO::NULL, "w")

test/reline/test_reline.rb

@@ -285,7 +285,7 @@ def test_set_input_and_output
     input, to_write = IO.pipe
     to_read, output = IO.pipe
     unless Reline.__send__(:input=, input)
-      omit "Setting to input is not effective on #{Reline::IOGate}"
+      omit "Setting to input is not effective on #{Reline.core.io_gate}"
     end
     Reline.output = output
 
@@ -303,12 +303,12 @@ def test_set_input_and_output
 
   def test_vi_editing_mode
     Reline.vi_editing_mode
-    assert_equal(Reline::KeyActor::ViInsert, Reline.send(:core).config.editing_mode.class)
+    assert_equal(Reline::KeyActor::ViInsert, Reline.core.config.editing_mode.class)
   end
 
   def test_emacs_editing_mode
     Reline.emacs_editing_mode
-    assert_equal(Reline::KeyActor::Emacs, Reline.send(:core).config.editing_mode.class)
+    assert_equal(Reline::KeyActor::Emacs, Reline.core.config.editing_mode.class)
   end
 
   def test_add_dialog_proc
@@ -374,12 +374,12 @@ def test_read_io
 
   def test_dumb_terminal
     lib = File.expand_path("../../lib", __dir__)
-    out = IO.popen([{"TERM"=>"dumb"}, Reline.test_rubybin, "-I#{lib}", "-rreline", "-e", "p Reline::IOGate"], &:read)
+    out = IO.popen([{"TERM"=>"dumb"}, Reline.test_rubybin, "-I#{lib}", "-rreline", "-e", "p Reline.core.io_gate"], &:read)
     assert_equal("Reline::GeneralIO", out.chomp)
   end
 
   def get_reline_encoding
-    if encoding = Reline::IOGate.encoding
+    if encoding = Reline.core.encoding
       encoding
     elsif RUBY_PLATFORM =~ /mswin|mingw/
       Encoding::UTF_8

test/reline/test_string_processing.rb

@@ -6,7 +6,7 @@ def setup
     @prompt = '> '
     @config = Reline::Config.new
     Reline::HISTORY.instance_variable_set(:@config, @config)
-    @encoding = Reline::IOGate.encoding
+    @encoding = Reline.core.encoding
     @line_editor = Reline::LineEditor.new(@config, @encoding)
     @line_editor.reset(@prompt, encoding: @encoding)
   end

test/reline/test_within_pipe.rb

@@ -3,14 +3,14 @@
 class Reline::WithinPipeTest < Reline::TestCase
   def setup
     Reline.send(:test_mode)
-    @encoding = Reline::IOGate.encoding
+    @encoding = Reline.core.encoding
     @input_reader, @writer = IO.pipe(@encoding)
     Reline.input = @input_reader
     @reader, @output_writer = IO.pipe(@encoding)
     @output = Reline.output = @output_writer
-    @config = Reline.send(:core).config
+    @config = Reline.core.config
     @config.keyseq_timeout *= 600 if defined?(RubyVM::RJIT) && RubyVM::RJIT.enabled? # for --jit-wait CI
-    @line_editor = Reline.send(:core).line_editor
+    @line_editor = Reline.core.line_editor
   end
 
   def teardown