anchor.diff:  
   include::
     XPath expression that specifies a subsection of the document that should be
  -  compared (asserted). Default is `./p/node()` for `inline_*:*` suites and
  +  compared (asserted). Default is `./p/node()` for `inline_*:*` groups and
     empty (i.e. `.`) for others.
   exclude::
     XPath expression that specifies parts of the document that should _not_ be
  
positive.code: 
  Test _example_ is just a document fragment in AsciiDoc syntax (a reference input), or the backend’s target syntax (an expected output).
  Example should consider one case of the generated output, i.e. it should reflect one code branch in a converter or template.
  Examples are grouped in _examples suites_. Each suite focuses on one block or inline element — more precisely Asciidoctor’s AST node (paragraph, table, anchor, footnote…).
  
  Examples suite is a text file named similar to Asciidoctor templates, i.e. the AST node name with an extension according to syntax, for example `block_table.adoc`, `block_table.html`. See below for a list of the AST nodes.
  Individual examples in the suite are separated by a special header with the name of the example, an optional description and options.
  
  Each example is identified by its name and the suite name like this: `{suite_name}:{example_name}` (e.g. `block_table:with_title`).
  Input and output examples are paired — for every input example there should be an output example with the same identifier.
  When you <<run-tests, run tests>>, the input example is converted using the tested backend (or templates) and its actual output is compared with the expected output example.
  
  
negative.code:   task.libs << 'test'
  end
  
  DocTest::GeneratorTask.new(:generate) do |task|
    task.output_suite = DocTest::HTML::ExamplesSuite.new(examples_path: 'test/examples/shiny')
    task.renderer_opts[:template_dirs] = 'data/templates'
    #
    # add extra input examples (optional)
    task.examples_path.unshift 'test/examples/asciidoc'
  end
  
  # When no task specified, run test.
  