Module: Hammer::Shell

Included in:
Hammer
Defined in:
lib/hammer/shell.rb

Overview

ANSI color/output helpers. Mixed into command instances; also callable directly as ‘Hammer::Shell.say(…)`.

Class Method Summary collapse

Class Method Details

.ask(prompt, default: nil) ⇒ Object 



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# File 'lib/hammer/shell.rb', line 47

def ask(prompt, default: nil)
  suffix = default ? " [#{default}]" : ''
  print paint("#{prompt}#{suffix}: ", :cyan)
  line = $stdin.gets
  return default if line.nil?
  line = line.chomp
  line.empty? ? default : line
end

.color!(value) ⇒ Object 



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# File 'lib/hammer/shell.rb', line 18

def color!(value)
  @color = value
end

.color? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/hammer/shell.rb', line 13

def color?
  return @color if defined?(@color)
  @color = $stdout.tty? && ENV['NO_COLOR'].nil?
end

.error(text) ⇒ Object

Raise a controlled Hammer::Error. If unhandled, the dispatcher prints the message in red and exits 1 - no backtrace, no help spam.

error 'config file missing' unless File.exist?(path)

Raises:

  • (Hammer::Error) 


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# File 'lib/hammer/shell.rb', line 37

def error(text)
  raise Hammer::Error, text
end

.paint(text, color = nil, bold: false) ⇒ Object 



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# File 'lib/hammer/shell.rb', line 22

def paint(text, color = nil, bold: false)
  return text.to_s unless color? && (color || bold)
  code = COLORS[color] || 0
  prefix = bold ? "\e[1;#{code}m" : "\e[#{code}m"
  "#{prefix}#{text}\e[0m"
end

.print_error(text) ⇒ Object

Print a red [error] line to stderr (does not exit). Used internally by the dispatcher to render Hammer::Error messages.



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# File 'lib/hammer/shell.rb', line 43

def print_error(text)
  warn paint("[error] #{text}", :red, bold: true)
end

.say(text = '', color = nil, bold: false) ⇒ Object 



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# File 'lib/hammer/shell.rb', line 29

def say(text = '', color = nil, bold: false)
  puts paint(text, color, bold: bold)
end

.sh(cmd) ⇒ Object

Run a shell command. Echoes the command in gray, raises Hammer::Error on non-zero exit. Returns true on success.



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# File 'lib/hammer/shell.rb', line 64

def sh(cmd)
  say "$ #{cmd}", :gray
  error "command failed: #{cmd}" unless system(cmd)
  true
end

.yes?(prompt) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/hammer/shell.rb', line 56

def yes?(prompt)
  answer = ask("#{prompt} (y/N)")
  return false if answer.nil?
  answer.to_s.strip.downcase.start_with?('y')
end