Running Watir code in rake task - ruby-on-rails

Question

Trying to run some Watir code as a Rake task that is giving me this error:
$ bundle exec rake update_market_rents:market_rents
DL is deprecated, please use Fiddle
(in C:/Users/310046998/sites/testpropinvest)
rake aborted!
LoadError: cannot load such file -- watir-webdriver
C:/Users/310046998/sites/testpropinvest/vendor/bundle/gems/activesupport-4.2.6/lib/active_support/dependencies.rb:274:in `require'
C:/Users/310046998/sites/testpropinvest/vendor/bundle/gems/activesupport-4.2.6/lib/active_support/dependencies.rb:274:in `block in require'
C:/Users/310046998/sites/testpropinvest/vendor/bundle/gems/activesupport-4.2.6/lib/active_support/dependencies.rb:240:in `load_dependency'
C:/Users/310046998/sites/testpropinvest/vendor/bundle/gems/activesupport-4.2.6/lib/active_support/dependencies.rb:274:in `require'
C:/Users/310046998/sites/testpropinvest/lib/tasks/update_market_rents.rake:10:in `block (2 levels) in <top (required)>'
C:/Users/310046998/sites/testpropinvest/vendor/bundle/gems/rake-11.3.0/exe/rake:27:in `<top (required)>'
Tasks: TOP => update_market_rents:market_rents
(See full trace by running task with --trace)
Code:
namespace :update_market_rents do
desc "TODO"
task market_rents: :environment do
#watir code
require 'watir-webdriver'
Selenium::WebDriver::Firefox::Binary.path='C:\Program Files\Mozilla Firefox\firefox.exe'
browser = Watir::Browser.new :ff
#blah blah more code
browser.close
end
end
If I run the Watir code from the command prompt using $ ruby filename.rb, I have no problems. For some reason, when I try to run it via the Rake command I get the above error. I'm struggling to find what's happening given that I see the code work okay alone.
I've tried adding require 'rubygems' but that doesn't work.

Answer 1

If you are on Linux then run:
sudo apt-get install nodejs
On Mac:
brew install node