1 files changed, 87 insertions, 0 deletions
diff --git a/jni/ruby/lib/rdoc/markup/to_table_of_contents.rb b/jni/ruby/lib/rdoc/markup/to_table_of_contents.rb
new file mode 100644
index 0000000..2e0f98c
--- /dev/null
+++ b/jni/ruby/lib/rdoc/markup/to_table_of_contents.rb
@@ -0,0 +1,87 @@
+##
+# Extracts just the RDoc::Markup::Heading elements from a
+# RDoc::Markup::Document to help build a table of contents
+
+class RDoc::Markup::ToTableOfContents < RDoc::Markup::Formatter
+
+  @to_toc = nil
+
+  ##
+  # Singleton for table-of-contents generation
+
+  def self.to_toc
+    @to_toc ||= new
+  end
+
+  ##
+  # Output accumulator
+
+  attr_reader :res
+
+  ##
+  # Omits headings with a level less than the given level.
+
+  attr_accessor :omit_headings_below
+
+  def initialize # :nodoc:
+    super nil
+
+    @omit_headings_below = nil
+  end
+
+  ##
+  # Adds +document+ to the output, using its heading cutoff if present
+
+  def accept_document document
+    @omit_headings_below = document.omit_headings_below
+
+    super
+  end
+
+  ##
+  # Adds +heading+ to the table of contents
+
+  def accept_heading heading
+    @res << heading unless suppressed? heading
+  end
+
+  ##
+  # Returns the table of contents
+
+  def end_accepting
+    @res
+  end
+
+  ##
+  # Prepares the visitor for text generation
+
+  def start_accepting
+    @omit_headings_below = nil
+    @res = []
+  end
+
+  ##
+  # Returns true if +heading+ is below the display threshold
+
+  def suppressed? heading
+    return false unless @omit_headings_below
+
+    heading.level > @omit_headings_below
+  end
+
+  # :stopdoc:
+  alias accept_block_quote     ignore
+  alias accept_raw             ignore
+  alias accept_rule            ignore
+  alias accept_blank_line      ignore
+  alias accept_paragraph       ignore
+  alias accept_verbatim        ignore
+  alias accept_list_end        ignore
+  alias accept_list_item_start ignore
+  alias accept_list_item_end   ignore
+  alias accept_list_end_bullet ignore
+  alias accept_list_start      ignore
+  # :startdoc:
+
+end
+