add additional mentions inline macro

- split mentions inline macro into two macros; one shorthand, one formal
- call convert instead of render on Inline
- update example

lib/mentions-inline-macro.rb

@@ -3,14 +3,29 @@
 include ::Asciidoctor
 
 Extensions.register do
+  # matches @username
   inline_macro do
-    named :mention
-    using_format :short
-    match /@(\w+)/
+    named :@mention
+    using_format :short # not required here for Asciidoctor >= 1.5.6
+    match %r/@(\w+)/
     process do |parent, target|
       mentions_uri_pattern = (parent.document.attr 'mentions-uri-pattern') || 'https://github.com/%s'
       mention_uri = mentions_uri_pattern % target
-      (create_anchor parent, %(@#{target}), type: :link, target: mention_uri).render
+      (create_anchor parent, %(@#{target}), type: :link, target: mention_uri).convert
+    end
+  end
+
+  # matches mention:username[<text>]
+  inline_macro do
+    named :mention
+    parse_content_as :text
+    process do |parent, target, attrs|
+      mentions_uri_pattern = (parent.document.attr 'mentions-uri-pattern') || 'https://github.com/%s'
+      mention_uri = mentions_uri_pattern % target
+      if (text = attrs['text']).empty?
+        text = %(@#{target})
+      end
+      (create_anchor parent, text, type: :link, target: mention_uri).convert
     end
   end
 end

lib/mentions-inline-macro/sample.adoc

@@ -1,4 +1,6 @@
 = Mentions Inline Macro
 :mentions-uri-pattern: http://twitter.com/%s
 
-@mojavelinux, do you have any feedback on this issue?
+@mojavelinux, wdyt?
+
+mention:mojavelinux[Dan] yo yo!