Add Wikipedia inline macro

gems/lib/asciidoctor/foodogsquared-extensions.rb

@@ -13,6 +13,7 @@ require_relative 'github-raw-content-include-processor/extension'
 require_relative 'gitlab-link-inline-macro/extension'
 require_relative 'gitlab-raw-content-include-processor/extension'
 require_relative 'chat-block-processor/extension'
+require_relative 'wikipedia-inline-macro/extension'
 
 Asciidoctor::Extensions.register do
   inline_macro ManInlineMacro
@@ -26,4 +27,6 @@ Asciidoctor::Extensions.register do
 
   inline_macro GitLabLinkInlineMacro
   include_processor GitLabRawIncludeProcessor
+
+  inline_macro WikipediaInlineMacro
 end

gems/lib/asciidoctor/wikipedia-inline-macro/README.adoc

@@ -0,0 +1,30 @@
+= Wikipedia inline macro
+:toc:
+
+
+An inline macro for easily creating Wikipedia links (i.e., `wikipedia.org`).
+
+
+== Synopsis
+
+[source, asciidoc]
+----
+wikipedia:PAGE[$CAPTION]
+----
+
+Where if `$CAPTION` is present, it will be used as the link text.
+Otherwise, it will just be the page.
+
+
+== Attributes
+
+- `lang` is the language domain to be linked into.
+By default, it is set to `en`.
+
+
+== Example usage
+
+- `wikipedia:Diff[]` should link to the link:https://en.wikipedia.org/wiki/Diff[Diff page on English Wikipedia].
+- `wikipedia:Diff[lang=ja]` should link to the link:https://ja.wikipedia.org/wiki/Diff[Diff page on Japanese Wikipedia].
+- `wikipedia:Photosynthesis[lang=simple]` should link to the link:https://simple.wikipedia.org/wiki/Photosynthesis[Photosynthesis page on Simple English Wikipedia].
+- `wikipedia:Diff[diff in Japanese Wikipedia, lang=ja]` should link to the link:https://ja.wikipedia.org/wiki/Diff[Diff page on Japanese Wikipedia] with the `diff in Japanese Wikipedia` as the link text.

gems/lib/asciidoctor/wikipedia-inline-macro/extension.rb

@@ -0,0 +1,20 @@
+# frozen_string_literal: true
+
+require 'uri'
+
+class WikipediaInlineMacro < Asciidoctor::Extensions::InlineMacroProcessor
+  use_dsl
+
+  named :wikipedia
+  name_positional_attributes 'caption'
+  default_attributes 'lang' => 'en'
+
+  def process(parent, target, attrs)
+    caption = attrs['caption'] || target
+    page = URI.encode_www_form_component target
+    link = %(https://#{attrs['lang']}.wikipedia.org/wiki/#{page})
+    node = create_anchor parent, caption, type: :link, target: link
+
+    create_inline parent, :quoted, node.convert
+  end
+end