Tweak and Refactor Pry::Terminal

The biggest behavior change is to favor `io/console` (but still not when
on jruby). The previous favorite was `Readline.get_screen_size`, but
that thing is stale just like the env. The only reason it gets updated
is if you put `Pry.auto_resize!` in your `~/.pryrc`

The next change is more error handling in `Pry.auto_resize!`

Otherwise I renamed `TerminalInfo` to `Terminal`, which is something
andrewvos and I discussed way back when `TerminalInfo` first came about.

The rest was a little Extract Method stuff, no biggie.

lib/pry.rb

@@ -267,6 +267,6 @@ require 'pry/pry_class'
 require 'pry/pry_instance'
 require 'pry/cli'
 require 'pry/pager'
-require 'pry/terminal_info'
+require 'pry/terminal'
 require 'pry/editor'
 require 'pry/rubygem'

lib/pry/helpers/table.rb

@@ -3,7 +3,7 @@ class Pry
     def self.tablify_or_one_line(heading, things)
       plain_heading = Pry::Helpers::Text.strip_color(heading)
       attempt = Table.new(things, :column_count => things.size)
-      if attempt.fits_on_line?(TerminalInfo.width! - plain_heading.size - 2)
+      if attempt.fits_on_line?(Terminal.width! - plain_heading.size - 2)
         "#{heading}: #{attempt}\n"
       else
         "#{heading}: \n#{tablify_to_screen_width(things, :indent => '  ')}\n"
@@ -13,10 +13,10 @@ class Pry
     def self.tablify_to_screen_width(things, options = {})
       things = things.compact
       if indent = options[:indent]
-        usable_width = TerminalInfo.width! - indent.size
+        usable_width = Terminal.width! - indent.size
         tablify(things, usable_width).to_s.gsub(/^/, indent)
       else
-        tablify(things, TerminalInfo.width!).to_s
+        tablify(things, Terminal.width!).to_s
       end
     end
 

lib/pry/indent.rb

@@ -1,12 +1,6 @@
 require 'coderay'
 
 class Pry
-  # Load io-console if possible, so that we can use $stdout.winsize.
-  begin
-    require 'io/console'
-  rescue LoadError
-  end
-
   ##
   # Pry::Indent is a class that can be used to indent a number of lines
   # containing Ruby code similar as to how IRB does it (but better). The class
@@ -392,7 +386,7 @@ class Pry
       full_line = prompt + code
       whitespace = ' ' * overhang
 
-      _, cols = TerminalInfo.screen_size
+      _, cols = Terminal.screen_size
 
       cols = cols.to_i
       lines = cols != 0 ? (full_line.length / cols + 1) : 1

lib/pry/pager.rb

@@ -27,7 +27,7 @@ class Pry::Pager
   end
 
   def self.page_size
-    rows = Pry::TerminalInfo.screen_size
+    rows = Pry::Terminal.screen_size
     @page_size ||= (rows && rows.first || 27)
   end
 

lib/pry/pry_class.rb

@@ -247,9 +247,16 @@ class Pry
 
   def self.auto_resize!
     trap :WINCH do
-      size = `stty size`.split(/\s+/).map &:to_i
-      Readline.set_screen_size *size
-      Readline.refresh_line
+      begin
+        Readline.set_screen_size *Terminal.size!
+      rescue => e
+        warn "\nPry.auto_resize!'s Readline.set_screen_size failed: #{e}"
+      end
+      begin
+        Readline.refresh_line
+      rescue => e
+        warn "\nPry.auto_resize!'s Readline.refresh_line failed: #{e}"
+      end
     end
   end
 

lib/pry/terminal.rb

@@ -0,0 +1,64 @@
+class Pry::Terminal
+  class << self
+    # Return a pair of [rows, columns] which gives the size of the window.
+    #
+    # If the window size cannot be determined, return nil.
+    def screen_size
+      rows, cols = actual_screen_size
+      if rows && cols
+        [rows.to_i, cols.to_i]
+      else
+        nil
+      end
+    end
+
+    # Return a screen size or a default if that fails.
+    def size! default = [25, 80]
+      screen_size || default
+    end
+
+    # Return a screen width or the default if that fails.
+    def width! default = 80
+      size![1]
+    end
+
+    def actual_screen_size
+      # The best way, if possible (requires non-jruby ≥1.9 or io-console gem)
+      screen_size_according_to_io_console or
+        # Fall back to the old standby, though it might be stale:
+        screen_size_according_to_env or
+        # Fall further back, though this one is also out of date without something
+        # calling Readline.set_screen_size
+        screen_size_according_to_readline or
+        # Windows users can otherwise run ansicon and get a decent answer:
+        screen_size_according_to_ansicon_env
+    end
+
+    def screen_size_according_to_io_console
+      return if Pry::Helpers::BaseHelpers.jruby?
+      require 'io/console'
+      $stdout.winsize if $stdout.tty? and $stdout.respond_to?(:winsize)
+    rescue LoadError
+      # They're probably on 1.8 without the io-console gem. We'll keep trying.
+    end
+
+    def screen_size_according_to_env
+      size = [ENV['LINES'] || ENV['ROWS'], ENV['COLUMNS']]
+      size if size[1].to_i > 0
+    end
+
+    def screen_size_according_to_readline
+      Readline.get_screen_size if Readline.respond_to?(:get_screen_size)
+    rescue Java::JavaLang::NullPointerException
+      # This rescue won't happen on jrubies later than:
+      #     https://github.com/jruby/jruby/pull/436
+      nil
+    end
+
+    def screen_size_according_to_ansicon_env
+      return unless ENV['ANSICON'] =~ /\((.*)x(.*)\)/
+      size = [$2, $1]
+      size if size[1].to_i > 0
+    end
+  end
+end

lib/pry/terminal_info.rb

@@ -1,48 +0,0 @@
-class Pry::TerminalInfo
-  # Return a pair of [rows, columns] which gives the size of the window.
-  #
-  # If the window size cannot be determined, return nil.
-  def self.screen_size
-    rows, cols = actual_screen_size
-    if rows && cols
-      [rows.to_i, cols.to_i]
-    else
-      nil
-    end
-  end
-
-  # Return a screen width or a default if it fails.
-  def self.width! default = 80
-    (screen_size || [nil, default])[1]
-  end
-
-  def self.actual_screen_size
-    [
-      # Some readlines also provides get_screen_size.
-      # Readline comes before IO#winsize because jruby sometimes defaults winsize to [25, 80]
-      readline_screen_size,
-
-      # io/console adds a winsize method to IO streams.
-      # rescue nil for jruby 1.7.0 [jruby/jruby#354]
-      $stdout.tty? && $stdout.respond_to?(:winsize) && ($stdout.winsize rescue nil),
-
-      # Otherwise try to use the environment (this may be out of date due
-      # to window resizing, but it's better than nothing).
-      [ENV["LINES"] || ENV["ROWS"], ENV["COLUMNS"]],
-
-      # If the user is running within ansicon, then use the screen size
-      # that it reports (same caveats apply as with ROWS and COLUMNS)
-      ENV['ANSICON'] =~ /\((.*)x(.*)\)/ && [$2, $1],
-    ].detect do |(_, cols)|
-      cols.to_i > 0
-    end
-  end
-
-  def self.readline_screen_size
-    Readline.get_screen_size if Readline.respond_to?(:get_screen_size)
-  rescue Java::JavaLang::NullPointerException
-    # This rescue won't happen on jrubies later than:
-    #     https://github.com/jruby/jruby/pull/436
-    nil
-  end
-end