file

# File railties/lib/rails_generator/commands.rb, line 177
        def file(relative_source, relative_destination, file_options = {}, &block)
          # Determine full paths for source and destination files.
          source              = source_path(relative_source)
          destination         = destination_path(relative_destination)
          destination_exists  = File.exists?(destination)

          # If source and destination are identical then we're done.
          if destination_exists and identical?(source, destination, &block)
            return logger.identical(relative_destination) 
          end

          # Check for and resolve file collisions.
          if destination_exists

            # Make a choice whether to overwrite the file.  :force and
            # :skip already have their mind made up, but give :ask a shot.
            choice = case (file_options[:collision] || options[:collision]).to_sym #|| :ask
              when :ask   then force_file_collision?(relative_destination)
              when :force then :force
              when :skip  then :skip
              else raise "Invalid collision option: #{options[:collision].inspect}"
            end

            # Take action based on our choice.  Bail out if we chose to
            # skip the file; otherwise, log our transgression and continue.
            case choice
              when :force then logger.force(relative_destination)
              when :skip  then return(logger.skip(relative_destination))
              else raise "Invalid collision choice: #{choice}.inspect"
            end

          # File doesn't exist so log its unbesmirched creation.
          else
            logger.create relative_destination
          end

          # If we're pretending, back off now.
          return if options[:pretend]

          # Write destination file with optional shebang.  Yield for content
          # if block given so templaters may render the source file.  If a
          # shebang is requested, replace the existing shebang or insert a
          # new one.
          File.open(destination, 'wb') do |df|
            File.open(source, 'rb') do |sf|
              if block_given?
                df.write(yield(sf))
              else
                if file_options[:shebang]
                  df.puts("#!#{file_options[:shebang]}")
                  if line = sf.gets
                    df.puts(line) if line !~ /^#!/
                  end
                end
                df.write(sf.read)
              end
            end
          end

          # Optionally change permissions.
          if file_options[:chmod]
            FileUtils.chmod(file_options[:chmod], destination)
          end
          
          # Optionally add file to subversion
          system("svn add #{destination}") if options[:svn]
        end