With the middleman v4 upgrade it is now required that filenames have fully qualified file extensions. For the most part, this means they need .html added after the filename before the rest of the extensions. This gist will help with the renaming process.

Insert .html to file names

path_to_project = "" # FILL ME IN

# Step 1: get a list of all the extensions you use

require 'set'
extensions = Set.new []

Dir.glob(path_to_project).each do |file|
  parts = file.split('.')
  extensions.merge(parts[1.. parts.length])
end

extensions.each do |extension|
  puts extension
end

# Step 2: convert the extensions you want converted

extensions_to_convert = [] # FILL ME IN

Dir.glob(path_to_project).each do |file|
  parts = file.split('.')
  should_convert_extension? = (parts & extensions_to_convert).any?
  already_converted? = parts.include? 'html'
  next unless should_convert_extension? and not already_converted?
  new_name = parts[0] + '.html.' + parts[1..parts.length].join('.')

  # verify file conversion
  puts "#{file} > #{new_name}"

  # uncomment to make actual changes
  # File.rename(file, new_name)
end