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

(https://github.com/ruby/reline/pull/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

3 files changed, 37 insertions, 29 deletions

diff --git a/lib/reline.rb b/lib/reline.rb
index 8da614aa2b..0a2dba4f0d 100644
--- a/lib/reline.rb
+++ b/lib/reline.rb
@@ -83,8 +83,12 @@ module Reline
       @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 @@ module Reline
 
     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 @@ module Reline
     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 @@ module Reline
 
     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
@@ -300,7 +304,7 @@ module Reline
 
     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')
@@ -308,7 +312,7 @@ module Reline
         $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 @@ module Reline
       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 @@ module Reline
         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 @@ module Reline
               @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 @@ module Reline
     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 @@ module Reline
       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 @@ module Reline
           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 @@ module Reline
       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 @@ module Reline
     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 @@ module Reline
   end
 
   def self.ungetc(c)
-    Reline::IOGate.ungetc(c)
+    core.io_gate.ungetc(c)
   end
 
   def self.line_editor
@@ -588,7 +592,7 @@ module Reline
 
     # 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)
diff --git a/lib/reline/ansi.rb b/lib/reline/ansi.rb
index 06ea9efd09..1e018d4e82 100644
--- a/lib/reline/ansi.rb
+++ b/lib/reline/ansi.rb
@@ -206,7 +206,7 @@ class Reline::ANSI
   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?
diff --git a/lib/reline/line_editor.rb b/lib/reline/line_editor.rb
index 404a595f9c..4030902139 100644
--- a/lib/reline/line_editor.rb
+++ b/lib/reline/line_editor.rb
@@ -60,6 +60,10 @@ class Reline::LineEditor
     reset_variables(encoding: encoding)
   end
 
+  def io_gate
+    Reline::IOGate
+  end
+
   def set_pasting_state(in_pasting)
     @in_pasting = in_pasting
   end