Introduce an abstracted structure about the encoding of Reline

The command prompt on Windows always uses Unicode to take input and print
output but most Reline implementation depends on Encoding.default_external.
This commit introduces an abstracted structure about the encoding of Reline.

5 files changed, 21 insertions, 9 deletions

diff --git a/lib/reline/ansi.rb b/lib/reline/ansi.rb
index cd780c6189..395721ea81 100644
--- a/lib/reline/ansi.rb
+++ b/lib/reline/ansi.rb
@@ -1,6 +1,10 @@
 require 'io/console'
 
 class Reline::ANSI
+  def self.encoding
+    Encoding.default_external
+  end
+
   RAW_KEYSTROKE_CONFIG = {
     [27, 91, 65] => :ed_prev_history,     # ↑
     [27, 91, 66] => :ed_next_history,     # ↓
diff --git a/lib/reline/general_io.rb b/lib/reline/general_io.rb
index 291c14c7b3..6281d5fbf6 100644
--- a/lib/reline/general_io.rb
+++ b/lib/reline/general_io.rb
@@ -1,6 +1,10 @@
 require 'timeout'
 
 class Reline::GeneralIO
+  def self.encoding
+    Encoding.default_external
+  end
+
   RAW_KEYSTROKE_CONFIG = {}
 
   @@buf = []
diff --git a/lib/reline/history.rb b/lib/reline/history.rb
index 238fcf2a76..d95f1cebc3 100644
--- a/lib/reline/history.rb
+++ b/lib/reline/history.rb
@@ -19,7 +19,7 @@ class Reline::History < Array
 
   def []=(index, val)
     index = check_index(index)
-    super(index, String.new(val, encoding: Encoding::default_external))
+    super(index, String.new(val, encoding: Reline.encoding_system_needs))
   end
 
   def concat(*val)
@@ -39,12 +39,12 @@ class Reline::History < Array
         val.shift(diff)
       end
     end
-    super(*(val.map{ |v| String.new(v, encoding: Encoding::default_external) }))
+    super(*(val.map{ |v| String.new(v, encoding: Reline.encoding_system_needs) }))
   end
 
   def <<(val)
     shift if size + 1 > @config.history_size
-    super(String.new(val, encoding: Encoding::default_external))
+    super(String.new(val, encoding: Reline.encoding_system_needs))
   end
 
   private def check_index(index)
diff --git a/lib/reline/line_editor.rb b/lib/reline/line_editor.rb
index 475f76fd65..dda602e155 100644
--- a/lib/reline/line_editor.rb
+++ b/lib/reline/line_editor.rb
@@ -57,10 +57,10 @@ class Reline::LineEditor
   NON_PRINTING_END = "\2"
   WIDTH_SCANNER = /\G(?:#{NON_PRINTING_START}|#{NON_PRINTING_END}|#{CSI_REGEXP}|#{OSC_REGEXP}|\X)/
 
-  def initialize(config)
+  def initialize(config, encoding)
     @config = config
     @completion_append_character = ''
-    reset_variables
+    reset_variables(encoding: encoding)
   end
 
   private def check_multiline_prompt(buffer, prompt)
@@ -85,10 +85,10 @@ class Reline::LineEditor
     end
   end
 
-  def reset(prompt = '', encoding = Encoding.default_external)
+  def reset(prompt = '', encoding:)
     @rest_height = (Reline::IOGate.get_screen_size.first - 1) - Reline::IOGate.cursor_pos.y
     @screen_size = Reline::IOGate.get_screen_size
-    reset_variables(prompt, encoding)
+    reset_variables(prompt, encoding: encoding)
     @old_trap = Signal.trap('SIGINT') {
       @old_trap.call if @old_trap.respond_to?(:call) # can also be string, ex: "DEFAULT"
       raise Interrupt
@@ -139,7 +139,7 @@ class Reline::LineEditor
     @eof
   end
 
-  def reset_variables(prompt = '', encoding = Encoding.default_external)
+  def reset_variables(prompt = '', encoding:)
     @prompt = prompt
     @mark_pointer = nil
     @encoding = encoding
diff --git a/lib/reline/windows.rb b/lib/reline/windows.rb
index aef3073a7e..4fbf243c37 100644
--- a/lib/reline/windows.rb
+++ b/lib/reline/windows.rb
@@ -1,6 +1,10 @@
 require 'fiddle/import'
 
 class Reline::Windows
+  def self.encoding
+    Encoding::UTF_8
+  end
+
   RAW_KEYSTROKE_CONFIG = {
     [224, 72] => :ed_prev_history, # ↑
     [224, 80] => :ed_next_history, # ↓
@@ -99,7 +103,7 @@ class Reline::Windows
         return @@input_buf.shift
       end
       begin
-        bytes = ret.chr(Encoding::UTF_8).encode(Encoding.default_external).bytes
+        bytes = ret.chr(Encoding::UTF_8).bytes
         @@input_buf.push(*bytes)
       rescue Encoding::UndefinedConversionError
         @@input_buf << ret