resolves asciidoctor#82 restructure configuration keys

- move asciidoc keys to Hash under asciidoc key
- use old keys if new keys aren't specified
- add warning if old structure is detected

lib/jekyll-asciidoc.rb

@@ -24,34 +24,48 @@ class AsciiDocConverter < Converter
       highlighter_suffix %(\n)
 
       def initialize(config)
-        @setup = false
-        (@config = config)['asciidoc'] ||= 'asciidoctor'
-        asciidoc_ext = (config['asciidoc_ext'] ||= 'asciidoc,adoc,ad')
-        asciidoc_ext_re = (config['asciidoc_ext_re'] = /^\.(?:#{asciidoc_ext.tr ',', '|'})$/ix)
-        config['asciidoc_page_attribute_prefix'] ||= 'page'
-        unless (asciidoctor_config = (config['asciidoctor'] ||= {})).frozen?
+        if String === (asciidoc_config = (config['asciidoc'] ||= {}))
+          ::Jekyll.logger.warn 'jekyll-asciidoc: The AsciiDoc config should be defined using a Hash (under the `asciidoc` key) instead of discrete entries.'
+          asciidoc_config = config['asciidoc'] = { 'processor' => asciidoc_config }
+        end
+        unless asciidoc_config.frozen?
+          asciidoc_config['processor'] ||= 'asciidoctor'
+          old_asciidoc_ext = config.delete('asciidoc_ext')
+          asciidoc_ext = (asciidoc_config['ext'] ||= (old_asciidoc_ext || 'asciidoc,adoc,ad'))
+          asciidoc_ext_re = (asciidoc_config['ext_re'] = /^\.(?:#{asciidoc_ext.tr ',', '|'})$/ix)
+          old_page_attr_prefix_def = config.key?('asciidoc_page_attribute_prefix')
+          old_page_attr_prefix_val = config.delete('asciidoc_page_attribute_prefix')
+          asciidoc_config['page_attribute_prefix'] ||= (old_page_attr_prefix_def ? old_page_attr_prefix_val : 'page')
+          asciidoc_config['require_front_matter_header'] = false unless asciidoc_config.key?('require_front_matter_header')
+
+          asciidoctor_config = (config['asciidoctor'] ||= {})
           asciidoctor_config.replace(::Hash[asciidoctor_config.map {|key, val| [key.to_sym, val] }])
           asciidoctor_config[:safe] ||= 'safe'
-          (asciidoctor_config[:attributes] ||= []).tap do |attributes|
-            attributes.unshift('notitle', 'idprefix', 'idseparator=-', 'linkattrs')
-            attributes.concat(IMPLICIT_ATTRIBUTES)
+          (asciidoctor_config[:attributes] ||= []).tap do |attrs|
+            attrs.unshift('notitle', 'idprefix', 'idseparator=-', 'linkattrs')
+            attrs.concat(IMPLICIT_ATTRIBUTES)
           end
-          if ::Jekyll::MIN_VERSION_3 && !config['asciidoc_require_front_matter']
+
+          if ::Jekyll::MIN_VERSION_3 && !asciidoc_config['require_front_matter']
             if (del_method = ::Jekyll::Utils.method(:has_yaml_header?))
               unless (new_method = ::Jekyll::AsciiDoc::Utils.method(:has_front_matter?)).respond_to?(:curry)
                 new_method = new_method.to_proc # Ruby < 2.2
               end
               del_method.owner.define_singleton_method(del_method.name, new_method.curry[del_method][asciidoc_ext_re])
             end
           end
+
+          asciidoc_config.freeze
           asciidoctor_config.freeze
         end
+        @setup = false
+        @config = config
       end
 
       def setup
         return self if @setup
         @setup = true
-        case @config['asciidoc']
+        case (processor = @config['asciidoc']['processor'])
         when 'asciidoctor'
           begin
             require 'asciidoctor' unless defined? ::Asciidoctor::VERSION
@@ -61,15 +75,15 @@ def setup
             raise ::FatalException.new('Missing dependency: asciidoctor')
           end
         else
-          STDERR.puts %(Invalid AsciiDoc processor: #{@config['asciidoc']})
+          STDERR.puts %(Invalid AsciiDoc processor: #{processor})
           STDERR.puts '  Valid options are [ asciidoctor ]'
-          raise ::FatalException.new(%(Invalid AsciiDoc processor: #{@config['asciidoc']}))
+          raise ::FatalException.new(%(Invalid AsciiDoc processor: #{processor}))
         end
         self
       end
 
       def matches(ext)
-        ext =~ @config['asciidoc_ext_re']
+        ext =~ @config['asciidoc']['ext_re']
       end
 
       def output_ext(ext)
@@ -82,11 +96,11 @@ def convert(content)
         if (standalone = content.start_with?(STANDALONE_HEADER))
           content = content[STANDALONE_HEADER.length..-1]
         end
-        case @config['asciidoc']
+        case (processor = @config['asciidoc']['processor'])
         when 'asciidoctor'
           ::Asciidoctor.convert(content, @config['asciidoctor'].merge(header_footer: standalone))
         else
-          warn 'Unknown AsciiDoc converter. Passing through unparsed content.'
+          warn %(Unknown AsciiDoc processor: #{processor}. Passing through unparsed content.)
           content
         end
       end
@@ -95,12 +109,12 @@ def load_header(content)
         setup
         # NOTE merely an optimization; if this doesn't match, the header still gets isolated by the processor
         header = content.split(HEADER_BOUNDARY_RE, 2)[0]
-        case @config['asciidoc']
+        case (processor = @config['asciidoc']['processor'])
         when 'asciidoctor'
           # NOTE return a document even if header is empty because attributes may be inherited from config
           ::Asciidoctor.load(header, @config['asciidoctor'].merge(parse_header_only: true))
         else
-          warn 'Unknown AsciiDoc converter. Cannot load document header.'
+          warn %(Unknown AsciiDoc processor: #{processor}. Cannot load document header.)
         end
       end
     end
@@ -122,7 +136,7 @@ def generate(site)
         @converter = (::Jekyll::MIN_VERSION_3 ?
             site.find_converter_instance(::Jekyll::Converters::AsciiDocConverter) :
             site.getConverterImpl(::Jekyll::Converters::AsciiDocConverter)).setup
-        unless (@page_attr_prefix = site.config['asciidoc_page_attribute_prefix']).empty?
+        unless (@page_attr_prefix = site.config['asciidoc']['page_attribute_prefix']).empty?
           @page_attr_prefix = %(#{@page_attr_prefix.chomp '-'}-)
         end