in jekyll/plugins/toc_generator.rb [39:49]
def populate_prev_next(site, toc)
hash = Hash.new
site.pages.each { |p| hash[p.path] = p }
missing_titles = Set.new
do_populate_prev_next(hash, toc, missing_titles)
missing_titles.each do |x|
puts "Page is missing titles for next/prev navigation: #{x}"
end
raise "Site has missing #{missing_titles.count} missing titles" if not missing_titles.empty?
end