Remove unused TOCGenerator (#23986)

app/lib/toc_generator.rb

@@ -1,69 +0,0 @@
-# frozen_string_literal: true
-
-class TOCGenerator
-  TARGET_ELEMENTS = %w(h1 h2 h3 h4 h5 h6).freeze
-  LISTED_ELEMENTS = %w(h2 h3).freeze
-
-  class Section
-    attr_accessor :depth, :title, :children, :anchor
-
-    def initialize(depth, title, anchor)
-      @depth    = depth
-      @title    = title
-      @children = []
-      @anchor   = anchor
-    end
-
-    delegate :<<, to: :children
-  end
-
-  def initialize(source_html)
-    @source_html = source_html
-    @processed   = false
-    @target_html = ''
-    @headers     = []
-    @slugs       = Hash.new { |h, k| h[k] = 0 }
-  end
-
-  def html
-    parse_and_transform unless @processed
-    @target_html
-  end
-
-  def toc
-    parse_and_transform unless @processed
-    @headers
-  end
-
-  private
-
-  def parse_and_transform
-    return if @source_html.blank?
-
-    parsed_html = Nokogiri::HTML.fragment(@source_html)
-
-    parsed_html.traverse do |node|
-      next unless TARGET_ELEMENTS.include?(node.name)
-
-      anchor = node['id'] || node.text.parameterize.presence || 'sec'
-      @slugs[anchor] += 1
-      anchor = "#{anchor}-#{@slugs[anchor]}" if @slugs[anchor] > 1
-
-      node['id'] = anchor
-
-      next unless LISTED_ELEMENTS.include?(node.name)
-
-      depth          = node.name[1..-1]
-      latest_section = @headers.last
-
-      if latest_section.nil? || latest_section.depth >= depth
-        @headers << Section.new(depth, node.text, anchor)
-      else
-        latest_section << Section.new(depth, node.text, anchor)
-      end
-    end
-
-    @target_html = parsed_html.to_s
-    @processed   = true
-  end
-end