Fixed ^A/^B and added support for Windows ConPty.

CHANGELOG.md

@@ -4,6 +4,15 @@
 
 * Fixed bug where reading from the `_out_` sticky local variable could return
   wrong results ([#2201](https://github.com/pry/pry/pull/2201))
+* Fixed issue with printing control characters `\001`/`^A` and `\002`/`^B`. ([#2209](https://github.com/pry/pry/pull/2209))
+  \
+  Added `Pry.config.escape_prompt` to manage adding those control characters to the prompt (the default is `true`).
+  It can then be disabled for terminals that don't have readline, or where readline's version doesn't support those characters.
+  \
+  Added support for [ConPty](https://devblogs.microsoft.com/commandline/windows-command-line-introducing-the-windows-pseudo-console-conpty/)
+  in Windows, which supports Ansi escapes natively.
+  \
+  Fixed all unit tests to run in Windows.
 
 ### [v0.14.1][v0.14.1] (April 12, 2021)
 

lib/pry/commands/easter_eggs.rb

@@ -83,15 +83,10 @@ class Pry
         \____/   \________________________|
       OUTPUT
 
-      move_up =
-        if Helpers::Platform.windows_ansi?
-          proc { |n| "\e[#{n}F" }
-        else
-          proc { |n| "\e[#{n}A\e[0G" }
-        end
+      move_up = "\e[F"
 
       output.puts "\n" * 6
-      output.puts picture.lines.map(&:chomp).reverse.join(move_up[1])
+      output.puts picture.lines.map(&:chomp).reverse.join(move_up)
       output.puts "\n" * 6
       output.puts "** ENV['TERM'] is #{ENV['TERM']} **\n\n"
 

lib/pry/config.rb

@@ -67,6 +67,9 @@ class Config
     # @return [Boolean]
     attribute :pager
 
+    # @return [Boolean]
+    attribute :escape_prompt
+
     # @return [Boolean] whether the global ~/.pryrc should be loaded
     attribute :should_load_rc
 
@@ -177,6 +180,7 @@ def initialize
 
         hooks: Pry::Hooks.default,
         pager: true,
+        escape_prompt: true,
         system: Pry::SystemCommandHandler.method(:default),
         color: Pry::Helpers::BaseHelpers.use_ansi_codes?,
         default_window_size: 5,

lib/pry/helpers/base_helpers.rb

@@ -36,8 +36,12 @@ def not_a_real_file?(file)
       end
 
       def use_ansi_codes?
-        Pry::Helpers::Platform.windows_ansi? ||
-          ((term = Pry::Env['TERM']) && term != "dumb")
+        Pry::Helpers::Platform.windows_ansi? || smart_term?
+      end
+
+      def smart_term?
+        term = Pry::Env['TERM']
+        term != nil && term != "dumb"
       end
 
       def colorize_code(code)

lib/pry/helpers/platform.rb

@@ -24,11 +24,46 @@ def self.windows?
         !!(RbConfig::CONFIG['host_os'] =~ /mswin|mingw/)
       end
 
+      # Checks older version of Windows console that required alternative
+      # libraries to work with Ansi escapes codes.
       # @return [Boolean]
       def self.windows_ansi?
-        return false unless windows?
+        # ensures that ConPty isn't available before checking anything else
+        windows? && !!(windows_conpty? || defined?(Win32::Console) || Pry::Env['ANSICON'] || mri_2?)
+      end
+
+      # New version of Windows console that understands Ansi escapes codes.
+      # @return [Boolean]
+      def self.windows_conpty?
+        @conpty ||= windows? && begin
+          require 'fiddle/import'
+          require 'fiddle/types'
+
+          kernel32 = Module.new do
+            extend Fiddle::Importer
+            dlload 'kernel32'
+            include Fiddle::Win32Types
+            extern 'HANDLE GetStdHandle(DWORD)'
+            extern 'BOOL GetConsoleMode(HANDLE, DWORD*)'
+          end
+
+          mode = kernel32.create_value('DWORD')
+
+          std_output_handle = -11
+          enable_virtual_terminal_processing = 0x4
+
+          stdout_handle = kernel32.GetStdHandle(std_output_handle)
+
+          stdout_handle > 0 &&
+            kernel32.GetConsoleMode(stdout_handle, mode) != 0 &&
+            mode.value & enable_virtual_terminal_processing != 0
 
-        !!(defined?(Win32::Console) || Pry::Env['ANSICON'] || mri_2?)
+        rescue LoadError, Fiddle::DLError
+          false
+        ensure
+          Fiddle.free mode.to_ptr if mode
+          kernel32.handler.handlers.each(&:close) if kernel32
+        end
       end
 
       # @return [Boolean]
@@ -53,7 +88,7 @@ def self.mri_19?
 
       # @return [Boolean]
       def self.mri_2?
-        mri? && RUBY_VERSION.start_with?('2')
+        mri? && RUBY_VERSION.start_with?('2.')
       end
     end
   end

lib/pry/helpers/text.rb

@@ -7,52 +7,70 @@ module Helpers
     module Text
       extend self
 
+      DECORATIONS = {
+        "bold" => '1',
+        "faint" => '2',
+        "italic" => '3',
+        "underline" => '4',
+        "blink" => '5',
+        "reverse" => '7'
+      }.freeze
+
       COLORS = {
-        "black" => 0,
-        "red" => 1,
-        "green" => 2,
-        "yellow" => 3,
-        "blue" => 4,
-        "purple" => 5,
-        "magenta" => 5,
-        "cyan" => 6,
-        "white" => 7
+        "black" => '0',
+        "red" => '1',
+        "green" => '2',
+        "yellow" => '3',
+        "blue" => '4',
+        "purple" => '5',
+        "magenta" => '5',
+        "cyan" => '6',
+        "white" => '7'
       }.freeze
 
+      DECORATIONS.each_pair do |decoration, color_code|
+        define_method decoration do |text|
+          escape_text(color_code, text)
+        end
+      end
+
       COLORS.each_pair do |color, value|
+        color_code = "0;3#{value}"
         define_method color do |text|
-          "\001\033[0;#{30 + value}m\002#{text}\001\033[0m\002"
+          escape_text(color_code, text)
         end
 
+        bright_color_code = "1;3#{value}"
         define_method "bright_#{color}" do |text|
-          "\001\033[1;#{30 + value}m\002#{text}\001\033[0m\002"
+          escape_text(bright_color_code, text)
         end
 
         COLORS.each_pair do |bg_color, bg_value|
+          bg_color_code = "#{color_code};4#{bg_value}"
           define_method "#{color}_on_#{bg_color}" do |text|
-            "\001\033[0;#{30 + value};#{40 + bg_value}m\002#{text}\001\033[0m\002"
+            escape_text(bg_color_code, text)
           end
 
+          bright_bg_color_code = "#{bright_color_code};4#{bg_value}"
           define_method "bright_#{color}_on_#{bg_color}" do |text|
-            "\001\033[1;#{30 + value};#{40 + bg_value}m\002#{text}\001\033[0m\002"
+            escape_text(bright_bg_color_code, text)
           end
         end
       end
 
+      # @param color_code [String]
+      # @param text [String]
+      # @return [String]
+      def escape_text(color_code, text)
+        "\e[#{color_code}m#{text}\e[0m"
+      end
+
       # Remove any color codes from _text_.
       #
       # @param  [String, #to_s] text
       # @return [String] _text_ stripped of any color codes.
       def strip_color(text)
-        text.to_s.gsub(/(\001)?(\e\[(\d[;\d]?)*m)(\002)?/, '')
-      end
-
-      # Returns _text_ as bold text for use on a terminal.
-      #
-      # @param [String, #to_s] text
-      # @return [String] _text_
-      def bold(text)
-        "\001\e[1m\002#{text}\001\e[0m\002"
+        text.to_s.gsub(/\001|\002|\e\[[\d;]*m/, '')
       end
 
       # Returns `text` in the default foreground colour.

lib/pry/indent.rb

@@ -9,7 +9,6 @@ class Pry
   # will be indented or un-indented by correctly.
   #
   class Indent
-    include Helpers::BaseHelpers
 
     # Raised if {#module_nesting} would not work.
     class UnparseableNestingError < StandardError; end
@@ -380,33 +379,5 @@ def module_nesting
         "#{kind} #{token}"
       end
     end
-
-    # Return a string which, when printed, will rewrite the previous line with
-    # the correct indentation. Mostly useful for fixing 'end'.
-    #
-    # @param [String] prompt The user's prompt
-    # @param [String] code The code the user just typed in
-    # @param [Integer] overhang The number of characters to erase afterwards (the
-    #   the difference in length between the old line and the new one)
-    #
-    # @return [String] correctly indented line
-    def correct_indentation(prompt, code, overhang = 0)
-      prompt = prompt.delete("\001\002")
-      line_to_measure = Pry::Helpers::Text.strip_color(prompt) << code
-      whitespace = ' ' * overhang
-
-      cols = @pry_instance.output.width
-      lines = cols == 0 ? 1 : (line_to_measure.length / cols + 1).to_i
-
-      if Helpers::Platform.windows_ansi?
-        move_up = "\e[#{lines}F"
-        move_down = "\e[#{lines}E"
-      else
-        move_up = "\e[#{lines}A\e[0G"
-        move_down = "\e[#{lines}B\e[0G"
-      end
-
-      "#{move_up}#{prompt}#{colorize_code(code)}#{whitespace}#{move_down}"
-    end
   end
 end

lib/pry/output.rb

@@ -5,8 +5,6 @@ class Output
     # @return [Array<Integer>] default terminal screen size [rows, cols]
     DEFAULT_SIZE = [27, 80].freeze
 
-    attr_reader :pry_instance
-
     def initialize(pry_instance)
       @output = pry_instance.config.output
       @color = pry_instance.config.color
@@ -75,6 +73,16 @@ def height
       size.first
     end
 
+    # Returns the number of lines it takes to fill a specified length.
+    #
+    # @param [Integer] length The length to check the number of lines
+    #
+    # @return [Integer] number of lines that the specified length occupies
+    def calculate_num_lines(length)
+      *, cols = size
+      cols == nil || cols == 0 ? 1 : (length / cols + 1).to_i
+    end
+
     private
 
     def actual_screen_size

lib/pry/pager.rb

@@ -144,7 +144,7 @@ def self.available?
           @system_pager =
             begin
               pager_executable = default_pager.split(' ').first
-              if Helpers::Platform.windows? || Helpers::Platform.windows_ansi?
+              if Helpers::Platform.windows?
                 `where /Q #{pager_executable}`
               else
                 `which #{pager_executable}`

lib/pry/pry_class.rb

@@ -143,7 +143,10 @@ def self.final_session_setup
     load_requires if Pry.config.should_load_requires
     load_history if Pry.config.history_load
     load_traps if Pry.config.should_trap_interrupts
-    load_win32console if Helpers::Platform.windows? && !Helpers::Platform.windows_ansi?
+
+    windows_no_ansi = Helpers::Platform.windows? && !Helpers::Platform.windows_ansi?
+
+    load_win32console if windows_no_ansi
   end
 
   # Start a Pry REPL.