Rails uninitialized constant Bundler (NameError)

Question

I\'m getting the following error when running any rails commands like rails s or rails c, it\'s also preventing my heroku app from starting (same e

Answer 1

These commands from the bundler FAQ did the trick:

#remove project-specific settings
rm -rf .bundle/

# remove project-specific cached gems and repos
rm -rf vendor/cache/

# remove the saved resolve of the Gemfile
rm -rf Gemfile.lock

and then rebundling with bundle install

edit: heroku deploy was also failing to start up because it starts the server with bin/rails s and my binstubs were all wonky. to fix this: BUNDLE INSTALL --BINSTUBS, again from bundler docs

Answer 2

I just removed the lock using rm -rf Gemfile.lock within my project directory's root folder, and re-ran bundle install and everything works perfect now.

Answer 3

I have problems like you, subscribe my case.

config/applicataion.rb:

require_relative 'boot'

require 'rails/all'

# Require the gems listed in Gemfile, including any gems
# you've limited to :test, :development, or :production.
Bundler.require(*Rails.groups)

module AppName
  class Application < Rails::Application
    config.load_defaults 5.2
  end
end

where require_relative 'boot' is very important, such as config/boot.rb:

ENV['BUNDLE_GEMFILE'] ||= File.expand_path('../Gemfile', __dir__)

require 'bundler/setup' # Set up gems listed in the Gemfile.

has including bundler library into application.