Add repo option for GitLab link inline macro

lib/asciidoctor/gitlab-link-inline-macro/README.adoc

@@ -23,6 +23,10 @@ By default. it doesn't point to anything which should be in the default branch o
 
 - `path` is the filepath to be linked.
 
+There are settings that is enabled with the link:https://docs.asciidoctor.org/asciidoc/latest/attributes/options/[options attribute].
+
+- `repo` sets the default caption to be the repo part.
+
 
 == Example usage
 

lib/asciidoctor/gitlab-link-inline-macro/extension.rb

@@ -12,7 +12,12 @@ class GitLabLinkInlineMacro < Asciidoctor::Extensions::InlineMacroProcessor
   def process(parent, target, attrs)
     doc = parent.document
 
-    text = attrs['caption'] || target
+    default_caption = if attrs.key?('repo-option')
+                        target.split('/').at(1)
+                      else
+                        target
+                      end
+    text = attrs['caption'] || default_caption
     uri = URI.parse %(https://#{attrs['domain']}/#{target})
 
     uri.path += %(/-/tree/#{attrs['rev']}) if attrs['rev']