upgrade to Asciidoctor 2.0.x

- upgrade to Asciidoctor 2.0.x (starting with 2.0.5)
- switch to fuzzy version match for asciidoctor gem
- disable sectanchors (since they get removed by the sanitizer anyway)
- use formal xref macro for interdocument xref in test
- add test for toggling the document title using showtitle/!showtitle
- add test to verify toc is generated at top of document when toc attribute is set

Gemfile

@@ -11,5 +11,5 @@ gem "org-ruby", "= 0.9.9"
 gem "creole", "~>0.3.6"
 gem "wikicloth", "=0.8.3"
 gem "twitter-text", "~> 1.14"
-gem "asciidoctor", "= 1.5.6.1"
+gem "asciidoctor", "~> 2.0.5"
 gem "rake"

lib/github/markups.rb

@@ -32,6 +32,7 @@
     'showtitle' => '@',
     'idprefix' => '',
     'idseparator' => '-',
+    'sectanchors' => nil,
     'docname' => File.basename(filename, (extname = File.extname(filename))),
     'docfilesuffix' => extname,
     'outfilesuffix' => extname,

test/markups/README.asciidoc

@@ -1,4 +1,6 @@
 = Document Title
+// sectanchors will be ignored
+:sectanchors:
 
 == First Section
 
@@ -7,7 +9,7 @@
 
 Refer to <<another-section>> or <<another-section-1>>.
 
-Navigate from {docname}{outfilesuffix} to <<another-document#,another document>>.
+Navigate from {docname}{outfilesuffix} to xref:another-document.asciidoc[another document].
 
 == Another Section
 

test/markups/README.hidetitle.asciidoc

@@ -0,0 +1,4 @@
+= Not Shown
+:!showtitle:
+
+This test verifies the author can disable the document title by adding `:!showtitle:` to the document header.

test/markups/README.hidetitle.asciidoc.html

@@ -0,0 +1,3 @@
+<div>
+<p>This test verifies the author can disable the document title by adding <code>:!showtitle:</code> to the document header.</p>
+</div>

test/markups/README.toc.asciidoc

@@ -0,0 +1,15 @@
+= Document Title
+:toc:
+:toc-title: Contents
+
+== Section A
+
+=== Subsection A-1
+
+=== Subsection A-2
+
+== Section B
+
+=== Subsection B-1
+
+=== Subsection B-2

test/markups/README.toc.asciidoc.html

@@ -0,0 +1,46 @@
+<h1>Document Title</h1>
+<div>
+<div>Contents</div>
+<ul>
+<li>
+<a href="#section-a">Section A</a>
+<ul>
+<li><a href="#subsection-a-1">Subsection A-1</a></li>
+<li><a href="#subsection-a-2">Subsection A-2</a></li>
+</ul>
+</li>
+<li>
+<a href="#section-b">Section B</a>
+<ul>
+<li><a href="#subsection-b-1">Subsection B-1</a></li>
+<li><a href="#subsection-b-2">Subsection B-2</a></li>
+</ul>
+</li>
+</ul>
+</div>
+<div>
+<h2>Section A</h2>
+<div>
+<div>
+<h3>Subsection A-1</h3>
+
+</div>
+<div>
+<h3>Subsection A-2</h3>
+
+</div>
+</div>
+</div>
+<div>
+<h2>Section B</h2>
+<div>
+<div>
+<h3>Subsection B-1</h3>
+
+</div>
+<div>
+<h3>Subsection B-2</h3>
+
+</div>
+</div>
+</div>