Get rid of deprecated code

app/views/devise/_links.erb

@@ -1,3 +0,0 @@
-<% ActiveSupport::Deprecation.warn "Rendering partials devise/_links.erb is deprecated" \
-  "please use devise/shared/_links.erb instead."%>
-<%= render "shared/links" %>

lib/devise.rb

@@ -227,18 +227,6 @@ module Devise
   mattr_accessor :clean_up_csrf_token_on_authentication
   @@clean_up_csrf_token_on_authentication = true
 
-  def self.encryptor=(value)
-    warn "\n[DEVISE] To select a encryption which isn't bcrypt, you should use devise-encryptable gem.\n"
-  end
-
-  def self.use_salt_as_remember_token=(value)
-    warn "\n[DEVISE] Devise.use_salt_as_remember_token is deprecated and has no effect. Please remove it.\n"
-  end
-
-  def self.apply_schema=(value)
-    warn "\n[DEVISE] Devise.apply_schema is deprecated and has no effect. Please remove it.\n"
-  end
-
   # PRIVATE CONFIGURATION
 
   # Store scopes mappings.

lib/devise/mailers/helpers.rb

@@ -35,12 +35,6 @@ module Devise
           :template_name => action
         }.merge(opts)
 
-        if resource.respond_to?(:headers_for)
-          ActiveSupport::Deprecation.warn "Calling headers_for in the model is no longer supported. " <<
-            "Please customize your mailer instead."
-          headers.merge!(resource.headers_for(action))
-        end
-
         @email = headers[:to]
         headers
       end

lib/devise/models.rb

@@ -56,15 +56,9 @@ module Devise
       klass.devise_modules.each do |mod|
         constant = const_get(mod.to_s.classify)
 
-        if constant.respond_to?(:required_fields)
         constant.required_fields(klass).each do |field|
           failed_attributes << field unless instance.respond_to?(field)
         end
-        else
-          ActiveSupport::Deprecation.warn "The module #{mod} doesn't implement self.required_fields(klass). " \
-            "Devise uses required_fields to warn developers of any missing fields in their models. " \
-            "Please implement #{mod}.required_fields(klass) that returns an array of symbols with the required fields."
-        end
       end
 
       if failed_attributes.any?

lib/devise/rails/routes.rb

@@ -222,14 +222,6 @@ module ActionDispatch::Routing
         routes  = mapping.used_routes
 
         devise_scope mapping.name do
-          if block_given?
-            ActiveSupport::Deprecation.warn "Passing a block to devise_for is deprecated. " \
-              "Please remove the block from devise_for (only the block, the call to " \
-              "devise_for must still exist) and call devise_scope :#{mapping.name} do ... end " \
-              "with the block instead", caller
-            yield
-          end
-
           with_devise_exclusive_scope mapping.fullpath, mapping.name, options do
             routes.each { |mod| send("devise_#{mod}", mapping, mapping.controllers) }
           end

lib/devise/strategies/authenticatable.rb

@@ -26,20 +26,8 @@ module Devise
       # In case the resource can't be validated, it will fail with the given
       # unauthenticated_message.
       def validate(resource, &block)
-        unless resource
-          ActiveSupport::Deprecation.warn "an empty resource was given to #{self.class.name}#validate. " \
-            "Please ensure the resource is not nil", caller
-        end
-
         result = resource && resource.valid_for_authentication?(&block)
 
-        case result
-        when Symbol, String
-          ActiveSupport::Deprecation.warn "valid_for_authentication? should return a boolean value"
-          fail!(result)
-          return false
-        end
-
         if result
           decorate(resource)
           true

test/models_test.rb

@@ -141,23 +141,4 @@ class CheckFieldsTest < ActiveSupport::TestCase
       Devise::Models.check_fields!(Magician)
     end
   end
-
-  test "doesn't raise a NoMethodError exception when the module doesn't have a required_field(klass) class method" do
-    driver = Class.new do
-      extend Devise::Models
-
-      def self.before_validation(instance)
-      end
-
-      attr_accessor :encrypted_password, :email
-
-      devise :database_authenticatable
-    end
-
-    swap_module_method_existence Devise::Models::DatabaseAuthenticatable, :required_fields do
-      assert_deprecated do
-        Devise::Models.check_fields!(driver)
-      end
-    end
-  end
 end

test/support/helpers.rb

@@ -67,25 +67,4 @@ class ActiveSupport::TestCase
       end
     end
   end
-
-  def swap_module_method_existence(klass, method)
-    klass.module_eval %Q[
-      class << self
-        alias #{method}_referenced #{method}
-        undef #{method}
-      end
-    ]
-
-    begin
-      yield if block_given?
-    ensure
-
-      klass.module_eval %Q[
-        class << self
-          alias #{method} #{method}_referenced
-          undef #{method}_referenced
-        end
-      ]
-    end
-  end
 end