haml--haml/lib/haml/exec.rb

require 'optparse'
require 'fileutils'
require 'rbconfig'

module Haml
  # This module handles the various Haml executables (`haml`, `sass`, `css2sass`, etc).
  module Exec
    # An abstract class that encapsulates the executable code for all three executables.
    class Generic
      # @param args [Array<String>] The command-line arguments
      def initialize(args)
        @args = args
        @options = {}
      end

      # Parses the command-line arguments and runs the executable.
      # Calls `Kernel#exit` at the end, so it never returns.
      def parse!
        begin
          @opts = OptionParser.new(&method(:set_opts))
          @opts.parse!(@args)

          process_result

          @options
        rescue Exception => e
          raise e if @options[:trace] || e.is_a?(SystemExit)

          $stderr.puts e.message
          exit 1
        end
        exit 0
      end

      # @return [String] A description of the executable
      def to_s
        @opts.to_s
      end

      protected

      # Finds the line of the source template
      # on which an exception was raised.
      #
      # @param exception [Exception] The exception
      # @return [String] The line number
      def get_line(exception)
        # SyntaxErrors have weird line reporting
        # when there's trailing whitespace,
        # which there is for Haml documents.
        return exception.message.scan(/:(\d+)/).first.first if exception.is_a?(::SyntaxError)
        exception.backtrace[0].scan(/:(\d+)/).first.first
      end

      # Tells optparse how to parse the arguments
      # available for all executables.
      #
      # This is meant to be overridden by subclasses
      # so they can add their own options.
      #
      # @param opts [OptionParser]
      def set_opts(opts)
        opts.on('-s', '--stdin', :NONE, 'Read input from standard input instead of an input file') do
          @options[:input] = $stdin
        end

        opts.on('--trace', :NONE, 'Show a full traceback on error') do
          @options[:trace] = true
        end

        if RbConfig::CONFIG['host_os'] =~ /mswin|windows/i
          opts.on('--unix-newlines', 'Use Unix-style newlines in written files.') do
            @options[:unix_newlines] = true
          end
        end

        opts.on_tail("-?", "-h", "--help", "Show this message") do
          puts opts
          exit
        end

        opts.on_tail("-v", "--version", "Print version") do
          puts("Haml/Sass #{::Haml.version[:string]}")
          exit
        end
      end

      # Processes the options set by the command-line arguments.
      # In particular, sets `@options[:input]` and `@options[:output]`
      # to appropriate IO streams.
      #
      # This is meant to be overridden by subclasses
      # so they can run their respective programs.
      def process_result
        input, output = @options[:input], @options[:output]
        args = @args.dup
        input ||=
          begin
            filename = args.shift
            @options[:filename] = filename
            open_file(filename) || $stdin
          end
        output ||= open_file(args.shift, 'w') || $stdout

        @options[:input], @options[:output] = input, output
      end

      private

      def open_file(filename, flag = 'r')
        return if filename.nil?
        flag = 'wb' if @options[:unix_newlines] && flag == 'w'
        File.open(filename, flag)
      end
    end

    # An abstrac class that encapsulates the code
    # specific to the `haml` and `sass` executables.
    class HamlSass < Generic
      # @param args [Array<String>] The command-line arguments
      def initialize(args)
        super
        @options[:for_engine] = {}
      end

      protected

      # Tells optparse how to parse the arguments
      # available for the `haml` and `sass` executables.
      #
      # This is meant to be overridden by subclasses
      # so they can add their own options.
      #
      # @param opts [OptionParser]
      def set_opts(opts)
        opts.banner = <<END
Usage: #{@name.downcase} [options] [INPUT] [OUTPUT]

Description:
  Uses the #{@name} engine to parse the specified template
  and outputs the result to the specified file.

Options:
END

        opts.on('--rails RAILS_DIR', "Install Haml and Sass from the Gem to a Rails project") do |dir|
          original_dir = dir

          dir = File.join(dir, 'vendor', 'plugins')

          unless File.exists?(dir)
            puts "Directory #{dir} doesn't exist"
            exit
          end

          dir = File.join(dir, 'haml')

          if File.exists?(dir)
            print "Directory #{dir} already exists, overwrite [y/N]? "
            exit if gets !~ /y/i
            FileUtils.rm_rf(dir)
          end

          begin
            Dir.mkdir(dir)
          rescue SystemCallError
            puts "Cannot create #{dir}"
            exit
          end

          File.open(File.join(dir, 'init.rb'), 'w') do |file|
            file << File.read(File.dirname(__FILE__) + "/../../init.rb")
          end

          puts "Haml plugin added to #{original_dir}"
          exit
        end

        opts.on('-c', '--check', "Just check syntax, don't evaluate.") do
          require 'stringio'
          @options[:check_syntax] = true
          @options[:output] = StringIO.new
        end

        super
      end

      # Processes the options set by the command-line arguments.
      # In particular, sets `@options[:for_engine][:filename]` to the input filename
      # and requires the appropriate file.
      #
      # This is meant to be overridden by subclasses
      # so they can run their respective programs.
      def process_result
        super
        @options[:for_engine][:filename] = @options[:filename] if @options[:filename]
        require File.dirname(__FILE__) + "/../#{@name.downcase}"
      end
    end

    # The `sass` executable.
    class Sass < HamlSass
      # @param args [Array<String>] The command-line arguments
      def initialize(args)
        super
        @name = "Sass"
        @options[:for_engine][:load_paths] = ['.'] + (ENV['SASSPATH'] || '').split(File::PATH_SEPARATOR)
      end

      protected

      # Tells optparse how to parse the arguments.
      #
      # @param opts [OptionParser]
      def set_opts(opts)
        super

        opts.on('--scss',
                'Use the CSS-superset SCSS syntax.') do
          @options[:for_engine][:syntax] = :scss
        end
        opts.on('--watch', 'Watch files or directories for changes.',
                           'The location of the generated CSS can be set using a colon:',
                           '  sass --watch input.sass:output.css',
                           '  sass --watch input-dir:output-dir') do
          @options[:watch] = true
        end
        opts.on('--update', 'Compile files or directories to CSS.',
                            'Locations are set like --watch.') do
          @options[:update] = true
        end
        opts.on('-t', '--style NAME',
                'Output style. Can be nested (default), compact, compressed, or expanded.') do |name|
          @options[:for_engine][:style] = name.to_sym
        end
        opts.on('-g', '--debug-info',
                'Emit extra information in the generated CSS that can be used by the FireSass Firebug plugin.') do
          @options[:for_engine][:debug_info] = true
        end
        opts.on('-l', '--line-numbers', '--line-comments',
                'Emit comments in the generated CSS indicating the corresponding sass line.') do
          @options[:for_engine][:line_numbers] = true
        end
        opts.on('-i', '--interactive',
                'Run an interactive SassScript shell.') do
          @options[:interactive] = true
        end
        opts.on('-I', '--load-path PATH', 'Add a sass import path.') do |path|
          @options[:for_engine][:load_paths] << path
        end
        opts.on('--cache-location PATH', 'The path to put cached Sass files. Defaults to .sass-cache.') do |loc|
          @options[:for_engine][:cache_location] = loc
        end
        opts.on('-C', '--no-cache', "Don't cache to sassc files.") do
          @options[:for_engine][:cache] = false
        end
      end

      # Processes the options set by the command-line arguments,
      # and runs the Sass compiler appropriately.
      def process_result
        if !@options[:update] && !@options[:watch] &&
            @args.first && @args.first.include?(':')
          if @args.size == 1
            @args = @args.first.split(':', 2)
          else
            @options[:update] = true
          end
        end

        return interactive if @options[:interactive]
        return watch_or_update if @options[:watch] || @options[:update]
        super

        begin
          input = @options[:input]
          output = @options[:output]

          @options[:syntax] ||= :scss if input.is_a?(File) && input.path =~ /\.scss$/
          tree =
            if input.is_a?(File) && !@options[:check_syntax]
              ::Sass::Files.tree_for(input.path, @options[:for_engine])
            else
              # We don't need to do any special handling of @options[:check_syntax] here,
              # because the Sass syntax checking happens alongside evaluation
              # and evaluation doesn't actually evaluate any code anyway.
              ::Sass::Engine.new(input.read(), @options[:for_engine]).to_tree
            end

          input.close() if input.is_a?(File)

          output.write(tree.render)
          output.close() if output.is_a? File
        rescue ::Sass::SyntaxError => e
          raise e if @options[:trace]
          raise e.sass_backtrace_str("standard input")
        end
      end

      private

      def interactive
        require 'sass'
        require 'sass/repl'
        ::Sass::Repl.new(@options).run
      end

      def watch_or_update
        require 'sass'
        require 'sass/plugin'
        ::Sass::Plugin.options.merge! @options[:for_engine]
        ::Sass::Plugin.options[:unix_newlines] = @options[:unix_newlines]

        if @args[1] && !@args[0].include?(':')
          flag = @options[:update] ? "--update" : "--watch"
          err =
            if !File.exist?(@args[1])
              "doesn't exist"
            elsif @args[1] =~ /\.css$/
              "is a CSS file"
            end
          raise <<MSG if err
File #{@args[1]} #{err}.
  Did you mean: sass #{flag} #{@args[0]}:#{@args[1]}
MSG
        end

        dirs, files = @args.map {|name| name.split(':', 2)}.
          map {|from, to| [from, to || from.gsub(/\..*?$/, '.css')]}.
          partition {|i, _| File.directory? i}
        ::Sass::Plugin.options[:template_location] = dirs

        ::Sass::Plugin.on_updating_stylesheet do |_, css|
          if File.exists? css
            puts_action :overwrite, :yellow, css
          else
            puts_action :create, :green, css
          end
        end

        ::Sass::Plugin.on_creating_directory {|dirname| puts_action :directory, :green, dirname}
        ::Sass::Plugin.on_deleting_css {|filename| puts_action :delete, :yellow, filename}
        ::Sass::Plugin.on_compilation_error do |error, _, _|
          raise error unless error.is_a?(::Sass::SyntaxError)
          puts_action :error, :red, "#{error.sass_filename} (Line #{error.sass_line}: #{error.message})"
        end

        if @options[:update]
          ::Sass::Plugin.update_stylesheets(files)
          return
        end

        puts ">>> Sass is watching for changes. Press Ctrl-C to stop."

        ::Sass::Plugin.on_template_modified {|template| puts ">>> Change detected to: #{template}"}
        ::Sass::Plugin.on_template_created {|template| puts ">>> New template detected: #{template}"}
        ::Sass::Plugin.on_template_deleted {|template| puts ">>> Deleted template detected: #{template}"}

        ::Sass::Plugin.watch(files)
      end

      # @private
      COLORS = { :red => 31, :green => 32, :yellow => 33 }

      def puts_action(name, color, arg)
        printf color(color, "%11s %s\n"), name, arg
      end

      def color(color, str)
        raise "[BUG] Unrecognized color #{color}" unless COLORS[color]

        # Almost any real Unix terminal will support color,
        # so we just filter for Windows terms (which don't set TERM)
        # and not-real terminals, which aren't ttys.
        return str if ENV["TERM"].empty? || !STDOUT.tty?
        return "\e[#{COLORS[color]}m#{str}\e[0m"
      end
    end

    # The `haml` executable.
    class Haml < HamlSass
      # @param args [Array<String>] The command-line arguments
      def initialize(args)
        super
        @name = "Haml"
        @options[:requires] = []
        @options[:load_paths] = []
      end

      # Tells optparse how to parse the arguments.
      #
      # @param opts [OptionParser]
      def set_opts(opts)
        super

        opts.on('-t', '--style NAME',
                'Output style. Can be indented (default) or ugly.') do |name|
          @options[:for_engine][:ugly] = true if name.to_sym == :ugly
        end

        opts.on('-f', '--format NAME',
                'Output format. Can be xhtml (default), html4, or html5.') do |name|
          @options[:for_engine][:format] = name.to_sym
        end

        opts.on('-e', '--escape-html',
                'Escape HTML characters (like ampersands and angle brackets) by default.') do
          @options[:for_engine][:escape_html] = true
        end

        opts.on('-q', '--double-quote-attributes',
                'Set attribute wrapper to double-quotes (default is single).') do
          @options[:for_engine][:attr_wrapper] = '"'
        end

        opts.on('-r', '--require FILE', "Same as 'ruby -r'.") do |file|
          @options[:requires] << file
        end

        opts.on('-I', '--load-path PATH', "Same as 'ruby -I'.") do |path|
          @options[:load_paths] << path
        end

        opts.on('--debug', "Print out the precompiled Ruby source.") do
          @options[:debug] = true
        end
      end

      # Processes the options set by the command-line arguments,
      # and runs the Haml compiler appropriately.
      def process_result
        super
        input = @options[:input]
        output = @options[:output]

        template = input.read()
        input.close() if input.is_a? File

        begin
          engine = ::Haml::Engine.new(template, @options[:for_engine])
          if @options[:check_syntax]
            puts "Syntax OK"
            return
          end

          @options[:load_paths].each {|p| $LOAD_PATH << p}
          @options[:requires].each {|f| require f}

          if @options[:debug]
            puts engine.precompiled
            puts '=' * 100
          end

          result = engine.to_html
        rescue Exception => e
          raise e if @options[:trace]

          case e
          when ::Haml::SyntaxError; raise "Syntax error on line #{get_line e}: #{e.message}"
          when ::Haml::Error;       raise "Haml error on line #{get_line e}: #{e.message}"
          else raise "Exception on line #{get_line e}: #{e.message}\n  Use --trace for backtrace."
          end
        end

        output.write(result)
        output.close() if output.is_a? File
      end
    end

    # The `html2haml` executable.
    class HTML2Haml < Generic
      # @param args [Array<String>] The command-line arguments
      def initialize(args)
        super
        @module_opts = {}
      end

      # Tells optparse how to parse the arguments.
      #
      # @param opts [OptionParser]
      def set_opts(opts)
        opts.banner = <<END
Usage: html2haml [options] [INPUT] [OUTPUT]

Description: Transforms an HTML file into corresponding Haml code.

Options:
END

        opts.on('-e', '--erb', 'Parse ERb tags.') do
          @module_opts[:erb] = true
        end

        opts.on('--no-erb', "Don't parse ERb tags.") do
          @options[:no_erb] = true
        end

        opts.on('-r', '--rhtml', 'Deprecated; same as --erb.') do
          @module_opts[:erb] = true
        end

        opts.on('--no-rhtml', "Deprecated; same as --no-erb.") do
          @options[:no_erb] = true
        end

        opts.on('-x', '--xhtml', 'Parse the input using the more strict XHTML parser.') do
          @module_opts[:xhtml] = true
        end

        super
      end

      # Processes the options set by the command-line arguments,
      # and runs the HTML compiler appropriately.
      def process_result
        super

        require 'haml/html'

        input = @options[:input]
        output = @options[:output]

        @module_opts[:erb] ||= input.respond_to?(:path) && input.path =~ /\.(rhtml|erb)$/
        @module_opts[:erb] &&= @options[:no_erb] != false

        output.write(::Haml::HTML.new(input, @module_opts).render)
      rescue ::Haml::Error => e
        raise "#{e.is_a?(::Haml::SyntaxError) ? "Syntax error" : "Error"} on line " +
          "#{get_line e}: #{e.message}"
      rescue LoadError => err
        dep = err.message.scan(/^no such file to load -- (.*)/)[0]
        raise err if @options[:trace] || dep.nil? || dep.empty?
        $stderr.puts "Required dependency #{dep} not found!\n  Use --trace for backtrace."
        exit 1
      end
    end

    # The `sass-convert` executable.
    class SassConvert < Generic
      # @param args [Array<String>] The command-line arguments
      def initialize(args)
        super
        @options[:for_tree] = {}
        @options[:for_engine] = {}
      end

      # Tells optparse how to parse the arguments.
      #
      # @param opts [OptionParser]
      def set_opts(opts)
        opts.banner = <<END
Usage: sass-convert [options] [INPUT] [OUTPUT]

Description:
  Converts between CSS, Sass, and SCSS files.
  E.g. converts from SCSS to Sass,
  or converts from CSS to SCSS (adding appropriate nesting).

Options:
END

        opts.on('-F', '--from FORMAT',
          'The format to convert from. Can be css, scss, sass, or sass2.',
          'sass2 is the same as sass, but updates more old syntax to new.',
          'By default, this is inferred from the input filename.',
          'If there is none, defaults to css.') do |name|
          @options[:from] = name.downcase.to_sym
        end

        opts.on('-T', '--to FORMAT',
          'The format to convert to. Can be scss or sass.',
          'By default, this is inferred from the output filename.',
          'If there is none, defaults to sass.') do |name|
          @options[:to] = name.downcase.to_sym
        end

        opts.on('-i', '--in-place',
          'Convert a file to its own syntax.',
          'This can be used to update some deprecated syntax.') do
          @options[:in_place] = true
        end

        opts.on('--old', 'Output the old-style ":prop val" property syntax.',
                         'Only meaningful when generating Sass.') do
          @options[:for_tree][:old] = true
        end

        opts.on('-C', '--no-cache', "Don't cache to sassc files.") do
          @options[:for_engine][:cache] = false
        end

        super
      end

      # Processes the options set by the command-line arguments,
      # and runs the CSS compiler appropriately.
      def process_result
        require 'sass'
        super

        input = @options[:input]
        output = @options[:output]
        output = input if @options[:in_place]

        if input.is_a?(File)
          @options[:from] ||=
            case input.path
            when /\.scss$/; :scss
            when /\.sass$/; :sass
            when /\.css$/; :css
            end
        elsif @options[:in_place]
          raise "Error: the --in-place option requires a filename."
        end

        if output.is_a?(File)
          @options[:to] ||=
            case output.path
            when /\.scss$/; :scss
            when /\.sass$/; :sass
            end
        end

        if @options[:from] == :sass2
          @options[:from] = :sass
          @options[:for_engine][:sass2] = true
        end

        @options[:from] ||= :css
        @options[:to] ||= :sass
        @options[:for_engine][:syntax] = @options[:from]

        out =
          if @options[:from] == :css
            require 'sass/css'
            ::Sass::CSS.new(input.read, @options[:for_tree]).render(@options[:to])
          else
            if input.is_a?(File)
              ::Sass::Files.tree_for(input.path, @options[:for_engine])
            else
              ::Sass::Engine.new(input.read, @options[:for_engine]).to_tree
            end.send("to_#{@options[:to]}", @options[:for_tree])
          end

        output = File.open(input.path, 'w') if @options[:in_place]
        output.write(out)
      rescue ::Sass::SyntaxError => e
        raise e if @options[:trace]
        raise "Syntax error on line #{get_line e}: #{e.message}\n  Use --trace for backtrace"
      end
    end
  end
end