Module: RDoc::Text

Overview

Methods for manipulating comment text

Constant Summary collapse

MARKUP_FORMAT =

Maps markup formats to classes that can parse them. If the format is unknown, “rdoc” format is used.

{
  'markdown' => RDoc::Markdown,
  'rdoc'     => RDoc::Markup,
  'rd'       => RDoc::RD,
  'tomdoc'   => RDoc::TomDoc,
}
TO_HTML_CHARACTERS =
Hash.new do |h, encoding|
  h[encoding] = {
    :close_dquote => encode_fallback('”', encoding, '"'),
    :close_squote => encode_fallback('’', encoding, '\''),
    :copyright    => encode_fallback('©', encoding, '(c)'),
    :ellipsis     => encode_fallback('…', encoding, '...'),
    :em_dash      => encode_fallback('—', encoding, '---'),
    :en_dash      => encode_fallback('–', encoding, '--'),
    :open_dquote  => encode_fallback('“', encoding, '"'),
    :open_squote  => encode_fallback('‘', encoding, '\''),
    :trademark    => encode_fallback('®', encoding, '(r)'),
  }
end

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.encode_fallback(character, encoding, fallback) ⇒ Object

Transcodes character to encoding with a fallback character.


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# File 'lib/rdoc/text.rb', line 59

def self.encode_fallback character, encoding, fallback
  character.encode(encoding, :fallback => { character => fallback },
                   :undef => :replace, :replace => fallback)
end

Instance Method Details

#expand_tabs(text) ⇒ Object

Expands tab characters in text to eight spaces


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# File 'lib/rdoc/text.rb', line 67

def expand_tabs text
  expanded = []

  text.each_line do |line|
    nil while line.gsub!(/(?:\G|\r)((?:.{8})*?)([^\t\r\n]{0,7})\t/) do
      r = "#{$1}#{$2}#{' ' * (8 - $2.size)}"
      r.force_encoding text.encoding if Object.const_defined? :Encoding
      r
    end

    expanded << line
  end

  expanded.join
end

#flush_left(text) ⇒ Object

Flush text left based on the shortest line


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# File 'lib/rdoc/text.rb', line 86

def flush_left text
  indent = 9999

  text.each_line do |line|
    line_indent = line =~ /\S/ || 9999
    indent = line_indent if indent > line_indent
  end

  empty = ''
  empty.force_encoding text.encoding if Object.const_defined? :Encoding

  text.gsub(/^ {0,#{indent}}/, empty)
end

#markup(text) ⇒ Object

Convert a string in markup format into HTML.

Requires the including class to implement #formatter


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# File 'lib/rdoc/text.rb', line 105

def markup text
  parse(text).accept formatter
end

#normalize_comment(text) ⇒ Object

Strips hashes, expands tabs then flushes text to the left


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# File 'lib/rdoc/text.rb', line 112

def normalize_comment text
  return text if text.empty?

  text = strip_stars    text
  text = strip_hashes   text
  text = expand_tabs    text
  text = flush_left     text
  text = strip_newlines text
  text
end

#parse(text, format = 'rdoc') ⇒ Object

Normalizes text then builds a RDoc::Markup::Document from it


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# File 'lib/rdoc/text.rb', line 126

def parse text, format = 'rdoc'
  return text if RDoc::Markup::Document === text
  return text.parse if RDoc::Comment === text

  text = normalize_comment text # TODO remove, should not be necessary

  return RDoc::Markup::Document.new if text =~ /\A\n*\z/

  MARKUP_FORMAT[format].parse text
end

#snippet(text, limit = 100) ⇒ Object

The first limit characters of text as HTML


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# File 'lib/rdoc/text.rb', line 140

def snippet text, limit = 100
  document = parse text

  RDoc::Markup::ToHtmlSnippet.new(options, limit).convert document
end

#strip_hashes(text) ⇒ Object

Strips leading # characters from text


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# File 'lib/rdoc/text.rb', line 149

def strip_hashes text
  return text if text =~ /^(?>\s*)[^\#]/

  empty = ''
  empty.force_encoding text.encoding if Object.const_defined? :Encoding

  text.gsub(/^\s*(#+)/) { $1.tr '#', ' ' }.gsub(/^\s+$/, empty)
end

#strip_newlines(text) ⇒ Object

Strips leading and trailing n characters from text


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# File 'lib/rdoc/text.rb', line 161

def strip_newlines text
  text.gsub(/\A\n*(.*?)\n*\z/m) do $1 end # block preserves String encoding
end

#strip_stars(text) ⇒ Object

Strips /* */ style comments


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# File 'lib/rdoc/text.rb', line 168

def strip_stars text
  return text unless text =~ %r%/\*.*\*/%m

  encoding = text.encoding if Object.const_defined? :Encoding

  text = text.gsub %r%Document-method:\s+[\w:.#=!?]+%, ''

  space = ' '
  space.force_encoding encoding if encoding

  text.sub!  %r%/\*+%       do space * $&.length end
  text.sub!  %r%\*+/%       do space * $&.length end
  text.gsub! %r%^[ \t]*\*%m do space * $&.length end

  empty = ''
  empty.force_encoding encoding if encoding
  text.gsub(/^\s+$/, empty)
end

#to_html(text) ⇒ Object

Converts ampersand, dashes, ellipsis, quotes, copyright and registered trademark symbols in text to properly encoded characters.


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# File 'lib/rdoc/text.rb', line 191

def to_html text
  if Object.const_defined? :Encoding then
    html = ''.encode text.encoding

    encoded = RDoc::Text::TO_HTML_CHARACTERS[text.encoding]
  else
    html = ''
    encoded = {
      :close_dquote => '”',
      :close_squote => '’',
      :copyright    => '©',
      :ellipsis     => '…',
      :em_dash      => '—',
      :en_dash      => '–',
      :open_dquote  => '“',
      :open_squote  => '‘',
      :trademark    => '®',
    }
  end

  s = StringScanner.new text
  insquotes = false
  indquotes = false
  after_word = nil

  until s.eos? do
    case
    when s.scan(/<(tt|code)>.*?<\/\1>/) then # skip contents of tt
      html << s.matched.gsub('\\\\', '\\')
    when s.scan(/<(tt|code)>.*?/) then
      warn "mismatched <#{s[1]}> tag" # TODO signal file/line
      html << s.matched
    when s.scan(/<[^>]+\/?s*>/) then # skip HTML tags
      html << s.matched
    when s.scan(/\\(\S)/) then # unhandled suppressed crossref
      html << s[1]
      after_word = nil
    when s.scan(/\.\.\.(\.?)/) then
      html << s[1] << encoded[:ellipsis]
      after_word = nil
    when s.scan(/\(c\)/) then
      html << encoded[:copyright]
      after_word = nil
    when s.scan(/\(r\)/) then
      html << encoded[:trademark]
      after_word = nil
    when s.scan(/---/) then
      html << encoded[:em_dash]
      after_word = nil
    when s.scan(/--/) then
      html << encoded[:en_dash]
      after_word = nil
    when s.scan(/&quot;|"/) then
      html << encoded[indquotes ? :close_dquote : :open_dquote]
      indquotes = !indquotes
      after_word = nil
    when s.scan(/``/) then # backtick double quote
      html << encoded[:open_dquote]
      after_word = nil
    when s.scan(/''/) then # tick double quote
      html << encoded[:close_dquote]
      after_word = nil
    when s.scan(/'/) then # single quote
      if insquotes
        html << encoded[:close_squote]
        insquotes = false
      elsif after_word
        # Mary's dog, my parents' house: do not start paired quotes
        html << encoded[:close_squote]
      else
        html << encoded[:open_squote]
        insquotes = true
      end

      after_word = nil
    else # advance to the next potentially significant character
      match = s.scan(/.+?(?=[<\\.("'`&-])/) #"

      if match then
        html << match
        after_word = match =~ /\w$/
      else
        html << s.rest
        break
      end
    end
  end

  html
end

#wrap(txt, line_len = 76) ⇒ Object

Wraps txt to line_len


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# File 'lib/rdoc/text.rb', line 285

def wrap(txt, line_len = 76)
  res = []
  sp = 0
  ep = txt.length

  while sp < ep
    # scan back for a space
    p = sp + line_len - 1
    if p >= ep
      p = ep
    else
      while p > sp and txt[p] != ?\s
        p -= 1
      end
      if p <= sp
        p = sp + line_len
        while p < ep and txt[p] != ?\s
          p += 1
        end
      end
    end
    res << txt[sp...p] << "\n"
    sp = p
    sp += 1 while sp < ep and txt[sp] == ?\s
  end

  res.join.strip
end