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Diffstat (limited to 'app/helpers/gitlab/gitlab_markdown_helper.rb')
| -rw-r--r-- | app/helpers/gitlab/gitlab_markdown_helper.rb | 195 |
1 files changed, 195 insertions, 0 deletions
diff --git a/app/helpers/gitlab/gitlab_markdown_helper.rb b/app/helpers/gitlab/gitlab_markdown_helper.rb new file mode 100644 index 00000000000..265cb4672fe --- /dev/null +++ b/app/helpers/gitlab/gitlab_markdown_helper.rb @@ -0,0 +1,195 @@ +require 'nokogiri' + +module Gitlab + module GitlabMarkdownHelper + include Gitlab::Markdown + include PreferencesHelper + + # Use this in places where you would normally use link_to(gfm(...), ...). + # + # It solves a problem occurring with nested links (i.e. + # "<a>outer text <a>gfm ref</a> more outer text</a>"). This will not be + # interpreted as intended. Browsers will parse something like + # "<a>outer text </a><a>gfm ref</a> more outer text" (notice the last part is + # not linked any more). link_to_gfm corrects that. It wraps all parts to + # explicitly produce the correct linking behavior (i.e. + # "<a>outer text </a><a>gfm ref</a><a> more outer text</a>"). + def link_to_gfm(body, url, html_options = {}) + return "" if body.blank? + + escaped_body = if body =~ /\A\<img/ + body + else + escape_once(body) + end + + gfm_body = gfm(escaped_body, {}, html_options) + + fragment = Nokogiri::XML::DocumentFragment.parse(gfm_body) + if fragment.children.size == 1 && fragment.children[0].name == 'a' + # Fragment has only one node, and it's a link generated by `gfm`. + # Replace it with our requested link. + text = fragment.children[0].text + fragment.children[0].replace(link_to(text, url, html_options)) + else + # Traverse the fragment's first generation of children looking for pure + # text, wrapping anything found in the requested link + fragment.children.each do |node| + next unless node.text? + node.replace(link_to(node.text, url, html_options)) + end + end + + fragment.to_html.html_safe + end + + MARKDOWN_OPTIONS = { + no_intra_emphasis: true, + tables: true, + fenced_code_blocks: true, + strikethrough: true, + lax_spacing: true, + space_after_headers: true, + superscript: true, + footnotes: true + }.freeze + + def markdown(text, options={}) + unless @markdown && options == @options + @options = options + + # see https://github.com/vmg/redcarpet#darling-i-packed-you-a-couple-renderers-for-lunch + rend = Redcarpet::Render::GitlabHTML.new(self, user_color_scheme_class, options) + + # see https://github.com/vmg/redcarpet#and-its-like-really-simple-to-use + @markdown = Redcarpet::Markdown.new(rend, MARKDOWN_OPTIONS) + end + + @markdown.render(text).html_safe + end + + def asciidoc(text) + Gitlab::Asciidoc.render(text, { + commit: @commit, + project: @project, + project_wiki: @project_wiki, + requested_path: @path, + ref: @ref + }) + end + + # Return the first line of +text+, up to +max_chars+, after parsing the line + # as Markdown. HTML tags in the parsed output are not counted toward the + # +max_chars+ limit. If the length limit falls within a tag's contents, then + # the tag contents are truncated without removing the closing tag. + def first_line_in_markdown(text, max_chars = nil, options = {}) + md = markdown(text, options).strip + + truncate_visible(md, max_chars || md.length) if md.present? + end + + def render_wiki_content(wiki_page) + case wiki_page.format + when :markdown + markdown(wiki_page.content) + when :asciidoc + asciidoc(wiki_page.content) + else + wiki_page.formatted_content.html_safe + end + end + + MARKDOWN_TIPS = [ + "End a line with two or more spaces for a line-break, or soft-return", + "Inline code can be denoted by `surrounding it with backticks`", + "Blocks of code can be denoted by three backticks ``` or four leading spaces", + "Emoji can be added by :emoji_name:, for example :thumbsup:", + "Notify other participants using @user_name", + "Notify a specific group using @group_name", + "Notify the entire team using @all", + "Reference an issue using a hash, for example issue #123", + "Reference a merge request using an exclamation point, for example MR !123", + "Italicize words or phrases using *asterisks* or _underscores_", + "Bold words or phrases using **double asterisks** or __double underscores__", + "Strikethrough words or phrases using ~~two tildes~~", + "Make a bulleted list using + pluses, - minuses, or * asterisks", + "Denote blockquotes using > at the beginning of a line", + "Make a horizontal line using three or more hyphens ---, asterisks ***, or underscores ___" + ].freeze + + # Returns a random markdown tip for use as a textarea placeholder + def random_markdown_tip + MARKDOWN_TIPS.sample + end + + private + + # Return +text+, truncated to +max_chars+ characters, excluding any HTML + # tags. + def truncate_visible(text, max_chars) + doc = Nokogiri::HTML.fragment(text) + content_length = 0 + truncated = false + + doc.traverse do |node| + if node.text? || node.content.empty? + if truncated + node.remove + next + end + + # Handle line breaks within a node + if node.content.strip.lines.length > 1 + node.content = "#{node.content.lines.first.chomp}..." + truncated = true + end + + num_remaining = max_chars - content_length + if node.content.length > num_remaining + node.content = node.content.truncate(num_remaining) + truncated = true + end + content_length += node.content.length + end + + truncated = truncate_if_block(node, truncated) + end + + doc.to_html + end + + # Used by #truncate_visible. If +node+ is the first block element, and the + # text hasn't already been truncated, then append "..." to the node contents + # and return true. Otherwise return false. + def truncate_if_block(node, truncated) + if node.element? && node.description.block? && !truncated + node.content = "#{node.content}..." if node.next_sibling + true + else + truncated + end + end + + # Returns the text necessary to reference `entity` across projects + # + # project - Project to reference + # entity - Object that responds to `to_reference` + # + # Examples: + # + # cross_project_reference(project, project.issues.first) + # # => 'namespace1/project1#123' + # + # cross_project_reference(project, project.merge_requests.first) + # # => 'namespace1/project1!345' + # + # Returns a String + def cross_project_reference(project, entity) + if entity.respond_to?(:to_reference) + "#{project.to_reference}#{entity.to_reference}" + else + '' + end + end + end +end |