Anyway to reload the modified gem files in the REPL

Question

While trying to build a Ruby gem (using Bundler), I tend to test the code using the REPL provided by Bundler - accessible via bundle console.

Is there any way to reload the entire project in it? I end up loading individual (changed) files again to test the new change.

Can you try [something similar here](http://stackoverflow.com/questions/10271676/reset-irb-console) ? — AnkitG, Mar 29 '14 at 14:26
Jikku were you able to solve this i'm trying to do the exact same thing. — acrogenesis, May 15 '15 at 02:07
No it didn't, got busy with few other pressing things that I just managed control the annoyance for some time. Seems, I need to learn about how exactly Ruby loads files to figure this out. — Jikku Jose, May 15 '15 at 02:09
You can try [something like this](http://stackoverflow.com/a/23677820/1949195)? — Marcos Tapajós, Jun 26 '15 at 01:01

AmitA · Answer 1 · 2015-09-11T23:09:23.530

The following hack works for a relatively simple gem of mine and Ruby 2.2.2. I'll be curious to see if it works for you. It makes the following assumptions:

You have the conventional folder structure: a file called lib/my_gem_name.rb and a folder lib/my_gem_name/ with any files / folder structure underneath.
All the classes you want to reload are nested within your top module MyGemName.

It will probably not work if in one of the files under lib/my_gem_name/ you monkey-patch classes outside of your MyGemName namespace.

If you're good with the assumptions above, put the following code inside the module definition in lib/my_gem_name.rb and give it a try:

module MyGemName

  def self.reload!
    Reloader.new(self).reload
  end

  class Reloader
    def initialize(top)
      @top = top
    end

    def reload
      cleanup
      load_all
    end

    private

    # @return [Array<String>] array of all files that were loaded to memory
    # under the lib/my_gem_name folder. 
    # This code makes assumption #1 above.  
    def loaded_files
      $LOADED_FEATURES.select{|x| x.starts_with?(__FILE__.chomp('.rb'))}
    end

    # @return [Array<Module>] Recursively find all modules and classes 
    # under the MyGemName namespace.
    # This code makes assumption number #2 above.
    def all_project_objects(current = @top)
      return [] unless current.is_a?(Module) and current.to_s.split('::').first == @top.to_s
      [current] + current.constants.flat_map{|x| all_project_objects(current.const_get(x))}
    end

    # @return [Hash] of the format {Module => true} containing all modules 
    #   and classes under the MyGemName namespace
    def all_project_objects_lookup
      @_all_project_objects_lookup ||= Hash[all_project_objects.map{|x| [x, true]}]
    end

    # Recursively removes all constant entries of modules and classes under
    # the MyGemName namespace
    def cleanup(parent = Object, current = @top)
      return unless all_project_objects_lookup[current]
      current.constants.each {|const| cleanup current, current.const_get(const)}
      parent.send(:remove_const, current.to_s.split('::').last.to_sym)
    end

    # Re-load all files that were previously reloaded
    def load_all
      loaded_files.each{|x| load x}
      true
    end
  end
end

If you don't want this functionality to be available in production, consider monkey-patching this in the bin/console script, but make sure to change the line $LOADED_FEATURES.select{|x| x.starts_with?(__FILE__.chomp('.rb'))} to something that will return a list of relevant loaded files given the new location of the code.

If you have a standard gem structure, this should work: $LOADED_FEATURES.select{|x| x.starts_with?(File.expand_path('../../lib/my_gem_name'))} (make sure to put your monkey patching code before the IRB.start or Pry.start)

Anyway to reload the modified gem files in the REPL

1 Answers1