Devise Params + RSpec + Shoulda Matcher

controller.rb

class Users::RegistrationsController < Devise::RegistrationsController
  before_action :configure_permitted_parameters

  def configure_permitted_parameters
    devise_parameter_sanitizer.for(:sign_in) { |u| u.permit(:email, info_attributes: [:name]) }
  end
end

test.rb

require 'rails_helper'
RSpec.describe Users::RegistrationsController do
  before { request.env["devise.mapping"] = Devise.mappings[:user] }

  describe 'POST #create' do
    it { should permit(:name, :email).for(:create) }
  end
end

Test output:

Randomized with seed 10217
F

Failures:

  1) Users::RegistrationsController POST #create should (for POST #create) restrict parameters to :name and :email
     Failure/Error: it { should permit(:name, :email).for(:create) }

       Expected POST #create to restrict parameters to :name and :email,
       but it did not restrict any parameters.
     # ./spec/controllers/users/registrations_controller_spec.rb:6:in `block (3 levels) in <top (required)>'

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1 example, 1 failure