refactors user model validations

app/models/user.rb

@@ -139,21 +139,21 @@ class User < ActiveRecord::Base
     presence: true,
     uniqueness: { case_sensitive: false }
 
-  validate :namespace_uniq, if: ->(user) { user.username_changed? }
+  validate :namespace_uniq, if: :username_changed?
   validate :avatar_type, if: ->(user) { user.avatar.present? && user.avatar_changed? }
-  validate :unique_email, if: ->(user) { user.email_changed? }
-  validate :owns_notification_email, if: ->(user) { user.notification_email_changed? }
-  validate :owns_public_email, if: ->(user) { user.public_email_changed? }
+  validate :unique_email, if: :email_changed?
+  validate :owns_notification_email, if: :notification_email_changed?
+  validate :owns_public_email, if: :public_email_changed?
   validate :signup_domain_valid?, on: :create, if: ->(user) { !user.created_by_id }
   validates :avatar, file_size: { maximum: 200.kilobytes.to_i }
 
   before_validation :sanitize_attrs
-  before_validation :set_notification_email, if: ->(user) { user.email_changed? }
-  before_validation :set_public_email, if: ->(user) { user.public_email_changed? }
+  before_validation :set_notification_email, if: :email_changed?
+  before_validation :set_public_email, if: :public_email_changed?
 
-  after_update :update_emails_with_primary_email, if: ->(user) { user.email_changed? }
+  after_update :update_emails_with_primary_email, if: :email_changed?
   before_save :ensure_authentication_token, :ensure_incoming_email_token
-  before_save :ensure_user_rights_and_limits, if: ->(user) { user.external_changed? }
+  before_save :ensure_user_rights_and_limits, if: :external_changed?
   after_save :ensure_namespace_correct
   after_initialize :set_projects_limit
   after_destroy :post_destroy_hook
@@ -1038,7 +1038,7 @@ class User < ActiveRecord::Base
       self.can_create_group = false
       self.projects_limit   = 0
     else
-      self.can_create_group = true
+      self.can_create_group = gitlab_config.default_can_create_group
       self.projects_limit = current_application_settings.default_projects_limit
     end
   end

spec/models/user_spec.rb

@@ -462,6 +462,8 @@ describe User, models: true do
       end
 
       it 'ensures correct rights and limits for user' do
+        stub_config_setting(default_can_create_group: true)
+
         expect { user.update_attributes(external: false) }.to change { user.can_create_group }.to(true)
           .and change { user.projects_limit }.to(current_application_settings.default_projects_limit)
       end