lib/rdoc/text.rb
# frozen_string_literal: true
##
# For RDoc::Text#to_html
require 'strscan'
##
# Methods for manipulating comment text
module RDoc::Text
##
# The language for this text. This affects stripping comments
# markers.
attr_accessor :language
##
# Maps markup formats to classes that can parse them. If the format is
# unknown, "rdoc" format is used.
MARKUP_FORMAT = {
'markdown' => RDoc::Markdown,
'rdoc' => RDoc::Markup,
'rd' => RDoc::RD,
'tomdoc' => RDoc::TomDoc,
}
MARKUP_FORMAT.default = RDoc::Markup
##
# Maps an encoding to a Hash of characters properly transcoded for that
# encoding.
#
# See also encode_fallback.
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
##
# Transcodes +character+ to +encoding+ with a +fallback+ character.
def self.encode_fallback character, encoding, fallback
character.encode(encoding, :fallback => { character => fallback },
:undef => :replace, :replace => fallback)
end
##
# Expands tab characters in +text+ to eight spaces
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 = RDoc::Encoding.change_encoding r, text.encoding
r
end
expanded << line
end
expanded.join
end
##
# Flush +text+ left based on the shortest line
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 = RDoc::Encoding.change_encoding empty, text.encoding
text.gsub(/^ {0,#{indent}}/, empty)
end
##
# Convert a string in markup format into HTML.
#
# Requires the including class to implement #formatter
def markup text
if @store.rdoc.options
locale = @store.rdoc.options.locale
else
locale = nil
end
if locale
i18n_text = RDoc::I18n::Text.new(text)
text = i18n_text.translate(locale)
end
parse(text).accept formatter
end
##
# Strips hashes, expands tabs then flushes +text+ to the left
def normalize_comment text
return text if text.empty?
case language
when :ruby
text = strip_hashes text
when :c
text = strip_stars text
end
text = expand_tabs text
text = flush_left text
text = strip_newlines text
text
end
##
# Normalizes +text+ then builds a RDoc::Markup::Document from it
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
##
# The first +limit+ characters of +text+ as HTML
def snippet text, limit = 100
document = parse text
RDoc::Markup::ToHtmlSnippet.new(options, limit).convert document
end
##
# Strips leading # characters from +text+
def strip_hashes text
return text if text =~ /^(?>\s*)[^\#]/
empty = ''
empty = RDoc::Encoding.change_encoding empty, text.encoding
text.gsub(/^\s*(#+)/) { $1.tr '#', ' ' }.gsub(/^\s+$/, empty)
end
##
# Strips leading and trailing \n characters from +text+
def strip_newlines text
text.gsub(/\A\n*(.*?)\n*\z/m) do $1 end # block preserves String encoding
end
##
# Strips /* */ style comments
def strip_stars text
return text unless text =~ %r%/\*.*\*/%m
encoding = text.encoding
text = text.gsub %r%Document-method:\s+[\w:.#=!?|^&<>~+\-/*\%@`\[\]]+%, ''
space = ' '
space = RDoc::Encoding.change_encoding space, encoding if encoding
text.sub! %r%/\*+% do space * $&.length end
text.sub! %r%\*+/% do space * $&.length end
text.gsub! %r%^[ \t]*\*%m do space * $&.length end
empty = ''
empty = RDoc::Encoding.change_encoding empty, encoding if encoding
text.gsub(/^\s+$/, empty)
end
##
# Converts ampersand, dashes, ellipsis, quotes, copyright and registered
# trademark symbols in +text+ to properly encoded characters.
def to_html text
html = (''.encode text.encoding).dup
encoded = RDoc::Text::TO_HTML_CHARACTERS[text.encoding]
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(/\(c\)/i) then
html << encoded[:copyright]
after_word = nil
when s.scan(/\(r\)/i) 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(/"|"/) 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(/(?:'|'){2}/) then # tick double quote
html << encoded[:close_dquote]
after_word = nil
when s.scan(/`/) then # backtick
if insquotes or after_word
html << '`'
after_word = false
else
html << encoded[:open_squote]
insquotes = true
end
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
##
# Wraps +txt+ to +line_len+
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
##
# Character class to be separated by a space when concatenating
# lines.
SPACE_SEPARATED_LETTER_CLASS = /[\p{Nd}\p{Lc}\p{Pc}]|[!-~&&\W]/
end