# frozen_string_literal: true # `CommonMark` markdown engine for GitLab's Banzai markdown filter. # This module is used in Banzai::Filter::MarkdownFilter. # Used gem is `commonmarker` which is a ruby wrapper for libcmark (CommonMark parser) # including GitHub's GFM extensions. # Homepage: https://github.com/gjtorikian/commonmarker module Banzai module Filter module MarkdownEngines class CommonMark EXTENSIONS = [ :autolink, # provides support for automatically converting URLs to anchor tags. :strikethrough, # provides support for strikethroughs. :table # provides support for tables. ].freeze PARSE_OPTIONS = [ :FOOTNOTES, # parse footnotes. :STRIKETHROUGH_DOUBLE_TILDE, # parse strikethroughs by double tildes (as redcarpet does). :VALIDATE_UTF8 # replace illegal sequences with the replacement character U+FFFD. ].freeze RENDER_OPTIONS_C = [ :GITHUB_PRE_LANG, # use GitHub-style
for fenced code blocks. :FOOTNOTES, # render footnotes. :FULL_INFO_STRING, # include full info strings of code blocks in separate attribute. :UNSAFE # allow raw/custom HTML and unsafe links. ].freeze # The `:GITHUB_PRE_LANG` option is not used intentionally because # it renders a fence block with language as `` # while GitLab's syntax is `some code\n
`. # If in the future the syntax is about to be made GitHub-compatible, please, add `:GITHUB_PRE_LANG` render option below # and remove `code_block` method from `lib/banzai/renderer/common_mark/html.rb`. RENDER_OPTIONS_RUBY = [ # as of commonmarker 0.18.0, we need to use :UNSAFE to get the same as the original :DEFAULT # https://github.com/gjtorikian/commonmarker/pull/81 :UNSAFE # allow raw/custom HTML and unsafe links. ].freeze def initialize(context) @context = context @renderer = Banzai::Renderer::CommonMark::HTML.new(options: render_options) if Feature.disabled?(:use_cmark_renderer, default_enabled: :yaml) end def render(text) if Feature.enabled?(:use_cmark_renderer, default_enabled: :yaml) CommonMarker.render_html(text, render_options, extensions) else doc = CommonMarker.render_doc(text, PARSE_OPTIONS, extensions) @renderer.render(doc) end end private def extensions if Feature.enabled?(:use_cmark_renderer, default_enabled: :yaml) EXTENSIONS else EXTENSIONS + [ :tagfilter # strips out several "unsafe" HTML tags from being used: https://github.github.com/gfm/#disallowed-raw-html-extension- ].freeze end end def render_options @context[:no_sourcepos] ? render_options_no_sourcepos : render_options_sourcepos end def render_options_no_sourcepos Feature.enabled?(:use_cmark_renderer, default_enabled: :yaml) ? RENDER_OPTIONS_C : RENDER_OPTIONS_RUBY end def render_options_sourcepos render_options_no_sourcepos + [ :SOURCEPOS # enable embedding of source position information ].freeze end end end end endsome code\n