LoadError when using bundle exec to run a script in Ruby 3 (using rvm)

Question

The following Ruby script gives me a LoadError when it requires the activesupport gem, but everything else is showing me that it's installed. I get the same error whether I run it through bundle exec or rvm do.

$ cat Gemfile | grep activesupport
gem 'activesupport'

$ bundle show activesupport
/Users/2b-software-mac/.rvm/gems/ruby-3.1.2/gems/activesupport-7.0.6

$ bundle exec ruby my_ruby_script.rb
Can I find the gem?
#<Bundler::StubSpecification name=activesupport version=7.0.6 platform=ruby>
Can I require the gem?
my_ruby_script.rb:4:in `require': cannot load such file -- activesupport (LoadError)
    from my_ruby_script.rb:4:in `<main>'

Script

puts 'Can I find the gem?'
puts Gem::Specification.find_all{ |g| g.name.include? 'activesupport' }
puts 'Can I require the gem?'
require 'activesupport'

Versions

• rvm 1.29.12
• ruby 3.1.2p20
• gem 3.3.7
• bundle 2.3.7
• macOS 13.5.2 (M2)

Answer 1

The gem has to be loaded like this (note the underscore):

require "active_support"

Read about Stand-Alone Active Support in the Rails Guides.