lib/rdoc/markup/to_rdoc.rb
# frozen_string_literal: true
##
# Outputs RDoc markup as RDoc markup! (mostly)
class RDoc::Markup::ToRdoc < RDoc::Markup::Formatter
##
# Current indent amount for output in characters
attr_accessor :indent
##
# Output width in characters
attr_accessor :width
##
# Stack of current list indexes for alphabetic and numeric lists
attr_reader :list_index
##
# Stack of list types
attr_reader :list_type
##
# Stack of list widths for indentation
attr_reader :list_width
##
# Prefix for the next list item. See #use_prefix
attr_reader :prefix
##
# Output accumulator
attr_reader :res
##
# Creates a new formatter that will output (mostly) \RDoc markup
def initialize markup = nil
super nil, markup
@markup.add_regexp_handling(/\\\S/, :SUPPRESSED_CROSSREF)
@width = 78
init_tags
@headings = {}
@headings.default = []
@headings[1] = ['= ', '']
@headings[2] = ['== ', '']
@headings[3] = ['=== ', '']
@headings[4] = ['==== ', '']
@headings[5] = ['===== ', '']
@headings[6] = ['====== ', '']
@hard_break = "\n"
end
##
# Maps attributes to HTML sequences
def init_tags
add_tag :BOLD, "<b>", "</b>"
add_tag :TT, "<tt>", "</tt>"
add_tag :EM, "<em>", "</em>"
end
##
# Adds +blank_line+ to the output
def accept_blank_line blank_line
@res << "\n"
end
##
# Adds +paragraph+ to the output
def accept_block_quote block_quote
@indent += 2
block_quote.parts.each do |part|
@prefix = '> '
part.accept self
end
@indent -= 2
end
##
# Adds +heading+ to the output
def accept_heading heading
use_prefix or @res << ' ' * @indent
@res << @headings[heading.level][0]
@res << attributes(heading.text)
@res << @headings[heading.level][1]
@res << "\n"
end
##
# Finishes consumption of +list+
def accept_list_end list
@list_index.pop
@list_type.pop
@list_width.pop
end
##
# Finishes consumption of +list_item+
def accept_list_item_end list_item
width = case @list_type.last
when :BULLET then
2
when :NOTE, :LABEL then
if @prefix then
@res << @prefix.strip
@prefix = nil
end
@res << "\n"
2
else
bullet = @list_index.last.to_s
@list_index[-1] = @list_index.last.succ
bullet.length + 2
end
@indent -= width
end
##
# Prepares the visitor for consuming +list_item+
def accept_list_item_start list_item
type = @list_type.last
case type
when :NOTE, :LABEL then
stripped_labels = Array(list_item.label).map do |label|
attributes(label).strip
end
bullets = case type
when :NOTE
stripped_labels.map { |b| "#{b}::" }
when :LABEL
stripped_labels.map { |b| "[#{b}]" }
end
bullets = bullets.join("\n")
bullets << "\n" unless stripped_labels.empty?
@prefix = ' ' * @indent
@indent += 2
@prefix << bullets + (' ' * @indent)
else
bullet = type == :BULLET ? '*' : @list_index.last.to_s + '.'
@prefix = (' ' * @indent) + bullet.ljust(bullet.length + 1)
width = bullet.length + 1
@indent += width
end
end
##
# Prepares the visitor for consuming +list+
def accept_list_start list
case list.type
when :BULLET then
@list_index << nil
@list_width << 1
when :LABEL, :NOTE then
@list_index << nil
@list_width << 2
when :LALPHA then
@list_index << 'a'
@list_width << list.items.length.to_s.length
when :NUMBER then
@list_index << 1
@list_width << list.items.length.to_s.length
when :UALPHA then
@list_index << 'A'
@list_width << list.items.length.to_s.length
else
raise RDoc::Error, "invalid list type #{list.type}"
end
@list_type << list.type
end
##
# Adds +paragraph+ to the output
def accept_paragraph paragraph
text = paragraph.text @hard_break
wrap attributes text
end
##
# Adds +paragraph+ to the output
def accept_indented_paragraph paragraph
@indent += paragraph.indent
text = paragraph.text @hard_break
wrap attributes text
@indent -= paragraph.indent
end
##
# Adds +raw+ to the output
def accept_raw raw
@res << raw.parts.join("\n")
end
##
# Adds +rule+ to the output
def accept_rule rule
use_prefix or @res << ' ' * @indent
@res << '-' * (@width - @indent)
@res << "\n"
end
##
# Outputs +verbatim+ indented 2 columns
def accept_verbatim verbatim
indent = ' ' * (@indent + 2)
verbatim.parts.each do |part|
@res << indent unless part == "\n"
@res << part
end
@res << "\n"
end
##
# Adds +table+ to the output
def accept_table header, body, aligns
widths = header.zip(body) do |h, b|
[h.size, b.size].max
end
aligns = aligns.map do |a|
case a
when nil
:center
when :left
:ljust
when :right
:rjust
end
end
@res << header.zip(widths, aligns) do |h, w, a|
h.__send__(a, w)
end.join("|").rstrip << "\n"
@res << widths.map {|w| "-" * w }.join("|") << "\n"
body.each do |row|
@res << row.zip(widths, aligns) do |t, w, a|
t.__send__(a, w)
end.join("|").rstrip << "\n"
end
end
##
# Applies attribute-specific markup to +text+ using RDoc::AttributeManager
def attributes text
flow = @am.flow text.dup
convert_flow flow
end
##
# Returns the generated output
def end_accepting
@res.join
end
##
# Removes preceding \\ from the suppressed crossref +target+
def handle_regexp_SUPPRESSED_CROSSREF target
text = target.text
text = text.sub('\\', '') unless in_tt?
text
end
##
# Adds a newline to the output
def handle_regexp_HARD_BREAK target
"\n"
end
##
# Prepares the visitor for text generation
def start_accepting
@res = [""]
@indent = 0
@prefix = nil
@list_index = []
@list_type = []
@list_width = []
end
##
# Adds the stored #prefix to the output and clears it. Lists generate a
# prefix for later consumption.
def use_prefix
prefix, @prefix = @prefix, nil
@res << prefix if prefix
prefix
end
##
# Wraps +text+ to #width
def wrap text
return unless text && !text.empty?
text_len = @width - @indent
text_len = 20 if text_len < 20
next_prefix = ' ' * @indent
prefix = @prefix || next_prefix
@prefix = nil
text.scan(/\G(?:([^ \n]{#{text_len}})(?=[^ \n])|(.{1,#{text_len}})(?:[ \n]|\z))/) do
@res << prefix << ($1 || $2) << "\n"
prefix = next_prefix
end
end
end