Create coverage file

 https://github.com/simplecov-ruby/simplecov

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Add gem file:

group :development, :test do

  # Call 'byebug' anywhere in the code to stop execution and get a debugger console

  gem 'byebug', platforms: [:mri, :mingw, :x64_mingw]

  gem 'simplecov', require: false

end

then install bundle install

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Add a spec/spec_helper.rb

require 'simplecov'

RSpec.configure do |config|

  SimpleCov.start 'rails'

end

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