Class: CommandTest::Parser

Inherits:
Object
  • Object
show all
Defined in:
lib/command_test/parser.rb

Instance Method Summary collapse

Instance Method Details

#extract_word(line) ⇒ Object 



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# File 'lib/command_test/parser.rb', line 37

def extract_word(line)
  return nil if line.empty?
  word = ''
  loop do
    if line.sub!(/\A"(([^"\\]|\\.)*)"/, '')
      chunk = $1.gsub(/\\(.)/, '\1')
    elsif line =~ /\A"/
      raise ArgumentError, "unmatched double quote: #{line}"
    elsif line.sub!(/\A'([^']*)'/, '')
      chunk = $1
    elsif line =~ /\A'/
      raise ArgumentError, "unmatched single quote: #{line}"
    elsif line.sub!(/\A\\(.)?/, '')
      chunk = $1 || ''
    elsif line.sub!(/\A([^\s\\'"<>]+)/, '')
      chunk = $1
    else
      line.lstrip!
      break
    end
    word << chunk
  end
  word
end

#extract_word_skipping_redirects(line) ⇒ Object 



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# File 'lib/command_test/parser.rb', line 19

def extract_word_skipping_redirects(line)
  while true
    if line.sub!(/\A\d*>>?(&\d+)?\s*/, '')
      if $1.nil?
        extract_word(line) or
          raise ArgumentError, "missing redirection target: #{line}"
      end
      next
    elsif line.sub!(/\A\d*<\s*/, '')
      extract_word(line) or
        raise ArgumentError, "missing redirection source: #{line}"
      next
    end

    return extract_word(line)
  end
end

#parse(line) ⇒ Object

Parse the given command line into words.

Supports backslash escaping, single quoting, double quoting, and redirects, a la bash.



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# File 'lib/command_test/parser.rb', line 9

def parse(line)
  # Implementation heavily inspired by Ruby's Shellwords.
  line = line.lstrip
  words = []
  while (word = extract_word_skipping_redirects(line))
    words << word
  end
  words
end