Disable code coverage by default

We can activate it on demand:

  COVERAGE=1 bundle exec rspec

We often run specs in chunks but simplecov needs all tests to be run.

spec/coverage_helper.rb

@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-unless !!ENV['CI']
+if ENV["COVERAGE"]
   require 'simplecov'
 
   SimpleCov.minimum_coverage 54

spec/spec_helper.rb

@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-unless ENV['CI']
+if ENV["COVERAGE"]
   require 'simplecov'
   SimpleCov.start 'rails'
 end