Module: Colsole

Defined in:
lib/colsole.rb,
lib/colsole/version.rb

Overview

Utility functions for colorful console applications.

Constant Summary collapse

ANSI_COLORS = 
{
  'n' => '',       # no color
  'k' => "\e[30m", # black
  'r' => "\e[31m", # red
  'g' => "\e[32m", # green
  'y' => "\e[33m", # yellow
  'b' => "\e[34m", # blue
  'm' => "\e[35m", # magenta
  'c' => "\e[36m", # cyan
  'w' => "\e[37m", # white
}
ANSI_STYLES = 
{
  'b' => "\e[1m", # bold
  'u' => "\e[4m", # underlined
  'i' => "\e[7m", # inverted
  'z' => "\e[0m", # terminate
}
VERSION = 
'1.0.0'

Class Method Summary collapse

Class Method Details

.colorize(string) ⇒ Object

Convert color markers to ansi colors.



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# File 'lib/colsole.rb', line 106

def colorize(string)
  process_color_markers string do |color, styles, text|
    "#{styles}#{color}#{text}#{ANSI_STYLES['z']}"
  end
end

.command_exist?(command) ⇒ Boolean

Returns true if the command exists in the path

Returns:

  • (Boolean) 


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# File 'lib/colsole.rb', line 50

def command_exist?(command)
  ENV['PATH'].split(File::PATH_SEPARATOR).any? do |dir|
    File.exist?(File.join dir, command) or File.exist?(File.join dir, "#{command}.exe")
  end
end

.internal_say(text, stream, replace: false) ⇒ Object 



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# File 'lib/colsole.rb', line 126

def internal_say(text, stream, replace: false)
  text = "\033[2K\r#{text}" if replace && terminal?
  last = text[-1, 1]
  handler = use_colors?(stream) ? :colorize : :strip_colors

  if terminal? && ((last == ' ') || (last == '\t'))
    stream.print send(handler, text)
  else
    stream.print send(handler, "#{text}\n")
  end
end

.process_color_markers(string) ⇒ Object 



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# File 'lib/colsole.rb', line 117

def process_color_markers(string)
  string.gsub(/([rgybmcn])([ubi]{0,3})`([^`]*)`/) do
    color = ANSI_COLORS[$1]
    styles = $2.chars.map { |a| ANSI_STYLES[a] }.join
    text = $3
    yield color, styles, text
  end
end

.safe_get_tty_size(default = [80, 30]) ⇒ Object 



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# File 'lib/colsole.rb', line 138

def safe_get_tty_size(default = [80, 30])
  return default unless IO.console

  begin
    IO.console.winsize.reverse
  rescue Errno::ENOTTY
    default
  end
end

.say(text, replace: false) ⇒ Object

Output a string with optional color markers to stdout. If text is ended with a white space, you can call again with replace: true to replace that line



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# File 'lib/colsole.rb', line 29

def say(text, replace: false)
  internal_say text, $stdout, replace: replace
end

.say!(text, replace: false) ⇒ Object

Output a string with optional color markers to stderr. Behaves similarly to ‘#say`.



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# File 'lib/colsole.rb', line 35

def say!(text, replace: false)
  internal_say text, $stderr, replace: replace
end

.strip_colors(string) ⇒ Object

Remove color markers.



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# File 'lib/colsole.rb', line 113

def strip_colors(string)
  process_color_markers(string) { |_color, _styles, text| text }
end

.terminal?(stream = $stdout) ⇒ Boolean

Returns true if stdout/stderr are a terminal

Returns:

  • (Boolean) 


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# File 'lib/colsole.rb', line 40

def terminal?(stream = $stdout)
  case ENV['TTY']
  when 'on'  then true
  when 'off' then false
  else
    stream.tty?
  end
end

.terminal_height ⇒ Object

Returns the rows part of the ‘#terminal_size`



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# File 'lib/colsole.rb', line 83

def terminal_height
  terminal_size[1]
end

.terminal_size(default = [80, 30]) ⇒ Object

Returns the terminal size as [columns, rows]. Environment variables can be used to cheat.



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# File 'lib/colsole.rb', line 63

def terminal_size(default = [80, 30])
  result = if (ENV['COLUMNS'] =~ /^\d+$/) && (ENV['LINES'] =~ /^\d+$/)
    [ENV['COLUMNS'].to_i, ENV['LINES'].to_i]
  else
    safe_get_tty_size default
  end

  unless result[0].is_a?(Integer) && result[1].is_a?(Integer) && result[0].positive? && result[1].positive?
    result = default
  end

  result
end

.terminal_width ⇒ Object

Returns the columns part of the ‘#terminal_size`



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# File 'lib/colsole.rb', line 78

def terminal_width
  terminal_size[0]
end

.use_colors?(stream = $stdout) ⇒ Boolean

Returns true if we can and should use colors in this stream

Returns:

  • (Boolean) 


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# File 'lib/colsole.rb', line 57

def use_colors?(stream = $stdout)
  ENV['FORCE_COLOR'] || (!ENV['NO_COLOR'] && terminal?(stream))
end

.word_wrap(text, length = nil) ⇒ Object

Converts a long string to be wrapped keeping words in tact. If the string starts with one or more spaces, they will be preserved in all subsequent lines (i.e., remain indented).



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# File 'lib/colsole.rb', line 90

def word_wrap(text, length = nil)
  length ||= terminal_width
  lead = text[/^\s*/]
  text.strip!
  length -= lead.length
  text.split("\n").collect! do |line|
    if line.length > length
      line.gsub!(/([^\s]{#{length}})([^\s$])/, '\\1 \\2')
      line.gsub(/(.{1,#{length}})(\s+|$)/, "#{lead}\\1\n").rstrip
    else
      "#{lead}#{line}"
    end
  end * "\n"
end