diff options
Diffstat (limited to 'lib/banzai/filter/spaced_link_filter.rb')
-rw-r--r-- | lib/banzai/filter/spaced_link_filter.rb | 77 |
1 files changed, 77 insertions, 0 deletions
diff --git a/lib/banzai/filter/spaced_link_filter.rb b/lib/banzai/filter/spaced_link_filter.rb new file mode 100644 index 00000000000..574a8a6c7a5 --- /dev/null +++ b/lib/banzai/filter/spaced_link_filter.rb @@ -0,0 +1,77 @@ +# frozen_string_literal: true + +require 'uri' + +module Banzai + module Filter + # HTML Filter for markdown links with spaces in the URLs + # + # Based on Banzai::Filter::AutolinkFilter + # + # CommonMark does not allow spaces in the url portion of a link. + # For example, `[example](page slug)` is not valid. However, + # in our wikis, we support (via RedCarpet) this type of link, allowing + # wiki pages to be easily linked by their title. This filter adds that functionality. + # The intent is for this to only be used in Wikis - in general, we want + # to adhere to CommonMark's spec. + # + class SpacedLinkFilter < HTML::Pipeline::Filter + include ActionView::Helpers::TagHelper + + # Pattern to match a standard markdown link + # + # Rubular: http://rubular.com/r/z9EAHxYmKI + LINK_PATTERN = /\[([^\]]+)\]\(([^)"]+)(?: \"([^\"]+)\")?\)/ + + # Text matching LINK_PATTERN inside these elements will not be linked + IGNORE_PARENTS = %w(a code kbd pre script style).to_set + + # The XPath query to use for finding text nodes to parse. + TEXT_QUERY = %Q(descendant-or-self::text()[ + not(#{IGNORE_PARENTS.map { |p| "ancestor::#{p}" }.join(' or ')}) + and contains(., ']\(') + ]).freeze + + def call + return doc if context[:markdown_engine] == :redcarpet + + doc.xpath(TEXT_QUERY).each do |node| + content = node.to_html + + next unless content.match(LINK_PATTERN) + + html = spaced_link_filter(content) + + next if html == content + + node.replace(html) + end + + doc + end + + private + + def spaced_link_match(link) + match = LINK_PATTERN.match(link) + return link unless match && match[1] && match[2] + + # escape the spaces in the url so that it's a valid markdown link, + # then run it through the markdown processor again, let it do its magic + text = match[1] + new_link = match[2].gsub(' ', '%20') + title = match[3] ? " \"#{match[3]}\"" : '' + html = Banzai::Filter::MarkdownFilter.call("[#{text}](#{new_link}#{title})", context) + + # link is wrapped in a <p>, so strip that off + html.sub('<p>', '').chomp('</p>') + end + + def spaced_link_filter(text) + Gitlab::StringRegexMarker.new(CGI.unescapeHTML(text), text.html_safe).mark(LINK_PATTERN) do |link, left:, right:| + spaced_link_match(link) + end + end + end + end +end |