I recently upgraded to Rails 5.1 from v4.3 and am now getting this error when running tests:
An error occurred while loading ./spec/controllers/admin/capacity_charges_controller_spec.rb.Failure/Error: require File.expand_path('../../config/environment', __FILE__)RuntimeError: can't modify frozen ArrayI get it for every test file. The line that triggers the error comes from rails_helper. I've checked rails 5.1 sample repos and there's nothing substantially different about our version.
The full stack trace is:
RuntimeError:can't modify frozen Array# /Users/jeremynagel/.rvm/gems/ruby-2.3.1@Rails4.2_EnergyLink/gems/actionpack-5.1.0/lib/action_dispatch/middleware/stack.rb:74:in `insert'# /Users/jeremynagel/.rvm/gems/ruby-2.3.1@Rails4.2_EnergyLink/gems/actionpack-5.1.0/lib/action_dispatch/middleware/stack.rb:74:in `insert'# /Users/jeremynagel/.rvm/gems/ruby-2.3.1@Rails4.2_EnergyLink/gems/actionpack-5.1.0/lib/action_dispatch/middleware/stack.rb:81:in `insert_after'# /Users/jeremynagel/.rvm/gems/ruby-2.3.1@Rails4.2_EnergyLink/gems/request_store-1.3.2/lib/request_store/railtie.rb:5:in `block in <class:Railtie>'# /Users/jeremynagel/.rvm/gems/ruby-2.3.1@Rails4.2_EnergyLink/gems/railties-5.1.0/lib/rails/initializable.rb:30:in `instance_exec'# /Users/jeremynagel/.rvm/gems/ruby-2.3.1@Rails4.2_EnergyLink/gems/railties-5.1.0/lib/rails/initializable.rb:30:in `run'# /Users/jeremynagel/.rvm/gems/ruby-2.3.1@Rails4.2_EnergyLink/gems/railties-5.1.0/lib/rails/initializable.rb:59:in `block in run_initializers'# /Users/jeremynagel/.rvm/gems/ruby-2.3.1@Rails4.2_EnergyLink/gems/railties-5.1.0/lib/rails/initializable.rb:58:in `run_initializers'# /Users/jeremynagel/.rvm/gems/ruby-2.3.1@Rails4.2_EnergyLink/gems/railties-5.1.0/lib/rails/application.rb:353:in `initialize!'# ./config/environment.rb:5:in `<top (required)>'# /Users/jeremynagel/.rvm/gems/ruby-2.3.1@Rails4.2_EnergyLink/gems/activesupport-5.1.0/lib/active_support/dependencies.rb:292:in `require'# /Users/jeremynagel/.rvm/gems/ruby-2.3.1@Rails4.2_EnergyLink/gems/activesupport-5.1.0/lib/active_support/dependencies.rb:292:in `block in require'# /Users/jeremynagel/.rvm/gems/ruby-2.3.1@Rails4.2_EnergyLink/gems/activesupport-5.1.0/lib/active_support/dependencies.rb:258:in `load_dependency'# /Users/jeremynagel/.rvm/gems/ruby-2.3.1@Rails4.2_EnergyLink/gems/activesupport-5.1.0/lib/active_support/dependencies.rb:292:in `require'# ./spec/rails_helper.rb:12:in `<top (required)>'# /Users/jeremynagel/.rvm/gems/ruby-2.3.1@Rails4.2_EnergyLink/gems/activesupport-5.1.0/lib/active_support/dependencies.rb:292:in `require'# /Users/jeremynagel/.rvm/gems/ruby-2.3.1@Rails4.2_EnergyLink/gems/activesupport-5.1.0/lib/active_support/dependencies.rb:292:in `block in require'# /Users/jeremynagel/.rvm/gems/ruby-2.3.1@Rails4.2_EnergyLink/gems/activesupport-5.1.0/lib/active_support/dependencies.rb:258:in `load_dependency'# /Users/jeremynagel/.rvm/gems/ruby-2.3.1@Rails4.2_EnergyLink/gems/activesupport-5.1.0/lib/active_support/dependencies.rb:292:in `require'# ./spec/controllers/admin/capacity_charges_controller_spec.rb:3:in `<top (required)>'# /Users/jeremynagel/.rvm/gems/ruby-2.3.1@Rails4.2_EnergyLink/gems/activesupport-5.1.0/lib/active_support/dependencies.rb:286:in `load'# /Users/jeremynagel/.rvm/gems/ruby-2.3.1@Rails4.2_EnergyLink/gems/activesupport-5.1.0/lib/active_support/dependencies.rb:286:in `block in load'# /Users/jeremynagel/.rvm/gems/ruby-2.3.1@Rails4.2_EnergyLink/gems/activesupport-5.1.0/lib/active_support/dependencies.rb:258:in `load_dependency'# /Users/jeremynagel/.rvm/gems/ruby-2.3.1@Rails4.2_EnergyLink/gems/activesupport-5.1.0/lib/active_support/dependencies.rb:286:in `load'