pry--pry/lib/pry/commands/reload_code.rb

class Pry
  class Command
    class ReloadCode < Pry::ClassCommand
      match 'reload-code'
      group 'Misc'
      description 'Reload the source file that contains the specified code object.'

      banner <<-'BANNER'
        Reload the source file that contains the specified code object.

        e.g reload-code MyClass#my_method    #=> reload a method
            reload-code MyClass              #=> reload a class
            reload-code my-command           #=> reload a pry command
            reload-code self                 #=> reload the current object
            reload-code                      #=> reload the current file or object
      BANNER

      def process
        if !args.empty?
          reload_object(args.join(" "))
        elsif internal_binding?(target)
          reload_object("self")
        else
          reload_current_file
        end
      end

      private

      def current_file
        file =
          if target.respond_to?(:source_location)
            target.source_location.first
          else
            target.eval("__FILE__")
          end
        File.expand_path file
      end

      def reload_current_file
        raise CommandError, "Current file: #{current_file} cannot be found on disk!" if !File.exist?(current_file)

        load current_file
        output.puts "The current file: #{current_file} was reloaded!"
      end

      def reload_object(identifier)
        code_object = Pry::CodeObject.lookup(identifier, _pry_)
        check_for_reloadability(code_object, identifier)
        load code_object.source_file
        output.puts "#{identifier} was reloaded!"
      end

      def check_for_reloadability(code_object, identifier)
        if !code_object || !code_object.source_file
          raise CommandError, "Cannot locate #{identifier}!"
        elsif !File.exist?(code_object.source_file)
          raise CommandError,
                "Cannot reload #{identifier} as it has no associated file on disk. " \
                "File found was: #{code_object.source_file}"
        end
      end
    end

    Pry::Commands.add_command(Pry::Command::ReloadCode)
    Pry::Commands.alias_command 'reload-method', 'reload-code'
  end
end