Use bare config accessors

Replace Spree::Config and Spree::Auth::Config[:foo] with the bare accessors.
Both dispatch to the same preferred_foo body; the bare form skips
has_preference!'s array scan and matches the form used by Solidus
core and most of this codebase.

A store that overrides preferred_foo on a configuration class no
longer affects these reads. Nothing in this workspace does that.

Author: jarednorman

README.md

@@ -36,7 +36,7 @@ To enable Devise's Confirmable module, which will send the user an email with a
 * Add this line to an initializer in your Rails project (typically `config/initializers/spree.rb`):
 
 ```ruby
-Spree::Auth::Config[:confirmable] = true
+Spree::Auth::Config.confirmable = true
 ```
 
 * Add a Devise initializer to your Rails project (typically `config/initializers/devise.rb`):

app/models/spree/user.rb

@@ -7,7 +7,7 @@ class User < Spree::Base
 
     devise :database_authenticatable, :registerable, :recoverable,
       :rememberable, :trackable, :validatable, :encryptable
-    devise :confirmable if Spree::Auth::Config[:confirmable]
+    devise :confirmable if Spree::Auth::Config.confirmable
 
     after_destroy :scramble_email_and_password
     after_discard :scramble_email_and_password

config/routes.rb

@@ -28,7 +28,7 @@
       post "/password/recover", to: "user_passwords#create", as: :reset_password
       get "/password/change", to: "user_passwords#edit", as: :edit_password
       put "/password/change", to: "user_passwords#update", as: :update_password
-      get "/confirm", to: "user_confirmations#show", as: :confirmation if Spree::Auth::Config[:confirmable]
+      get "/confirm", to: "user_confirmations#show", as: :confirmation if Spree::Auth::Config.confirmable
     end
 
     get "/checkout/registration", to: "checkout#registration", as: :checkout_registration

lib/controllers/frontend/spree/users_controller.rb

@@ -38,7 +38,7 @@ def update
 
       if params[:user][:password].present?
         # this logic needed b/c devise wants to log us out after password changes
-        if Spree::Auth::Config[:signout_after_password_change]
+        if Spree::Auth::Config.signout_after_password_change
           redirect_url = spree.login_url
         else
           bypass_sign_in(@user)

lib/generators/solidus/auth/install/templates/config/initializers/devise.rb.erb

@@ -1,4 +1,4 @@
 # frozen_string_literal: true
 
 Devise.secret_key = '<%= SecureRandom.hex(64) %>'
-Devise.email_regexp = Spree::Config[:default_email_regexp]
+Devise.email_regexp = Spree::Config.default_email_regexp

lib/patches/frontend/controllers/solidus_auth_devise/checkout_controller_patch.rb

@@ -50,7 +50,7 @@ def check_registration
     end
 
     def registration_required?
-      Spree::Auth::Config[:registration_step] &&
+      Spree::Auth::Config.registration_step &&
         !already_registered?
     end
 
@@ -60,7 +60,7 @@ def already_registered?
 
     def guest_authenticated?
       current_order&.email.present? &&
-        Spree::Config[:allow_guest_checkout]
+        Spree::Config.allow_guest_checkout
     end
 
     # Overrides the equivalent method defined in Spree::Core.  This variation of the method will ensure that users

lib/views/frontend/spree/checkout/registration.html.erb

@@ -4,7 +4,7 @@
   <div id="account" class="columns alpha eight">
     <%= render template: 'spree/user_sessions/new' %>
   </div>
-  <% if Spree::Config[:allow_guest_checkout] %>
+  <% if Spree::Config.allow_guest_checkout %>
     <div id="guest_checkout" data-hook class="columns omega eight">
       <h6><%= t('spree.guest_user_account') %></h6>
       <% if flash[:registration_error] %>