Convert less to sass

README.md

Convert .less files to .scss

To run:

cd root-directory-of-project/
ruby less-to-sass.rb

# or
ruby less-to-sass.rb <file-glob-to-convert>

Warning: This will delete the .less files it converts and replace them with .scss equivalents

Things this script doesn't do:

1. Convert mixins with when-directives
2. Simply removes quotes on ~"unescaped" strings
3. Convert class-like mixins .foo { } .bar { .foo(); }
4. Some more minor bugs

less-to-sass.rb

#!/usr/bin/env ruby

file_pattern = ARGV[0] || "**/*.less"

puts "Converting #{file_pattern} in current directory"

def convert_file(file)
  contents = open(file).read
  contents = convert_string_tildes contents
  contents = convert_string_interpolations contents
  contents = convert_variables contents
  contents = convert_mixins contents
  contents = convert_media_queries contents
  write_sass file, contents
end

def convert_variables(less)
  less.gsub /@((?!media|include|import|font-face|-moz-keyframes|-webkit-keyframes|keyframes|-o-keyframes)[a-zA-Z_]*)/, '$\1'
end

def convert_mixins(less)
  less.gsub(/^(\s*)\.([^(;]+\([^)]*\)\W*\{)/, '\1@mixin \2')
    .gsub(/^(\s*)[.#]([^(;{]*\(.*\)\W*;)/, '\1@include \2')
end

def convert_media_queries(less)
  less.gsub(/@media \$([^{]*)/, '@include media-\1')
end

def convert_string_interpolations(less)
  less.gsub(/\@\{([^}]*)\}/, '#{@\1}')
end

def convert_string_tildes(less)
  less.gsub(/~"([^"]*)"/, '\1')
end

def write_sass(file_name, sass)
  File.open(file_name.gsub(/\.less$/, '.scss'), 'w') do |f|
    f.write sass
    puts "Wrote #{file_name}"
  end

  File.delete file_name
end

files = Dir.glob(file_pattern)

files.each do |file|
  convert_file file
end