wip

app/mailers/devise/mailer.rb

@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-if defined?(ActionMailer)
+if Object.const_defined?(Devise.parent_mailer)
   class Devise::Mailer < Devise.parent_mailer.constantize
     include Devise::Mailers::Helpers
 

test/mailers/confirmation_instructions_test.rb

@@ -102,10 +102,13 @@ class ConfirmationInstructionsTest < ActionMailer::TestCase
 
   test 'renders a scoped if scoped_views is set in the mailer class' do
     begin
+      # Devise.send(:remove_const, :Mailer) if defined?(Devise::Mailer)
+      # load "#{Devise::Engine.root}/app/mailers/devise/mailer.rb"
       Devise::Mailer.scoped_views = true
       assert_equal user.email, mail.body.decoded
     ensure
       Devise::Mailer.send :remove_instance_variable, :@scoped_views
+      # Devise.send(:remove_const, :Mailer) if defined?(Devise::Mailer)
     end
   end
 

test/mailers/mailer_test.rb

@@ -4,6 +4,8 @@ require "test_helper"
 
 class MailerTest < ActionMailer::TestCase
   test "pass given block to #mail call" do
+    # Devise.send(:remove_const, :Mailer) if defined?(Devise::Mailer)
+    # load "#{Devise::Engine.root}/app/mailers/devise/mailer.rb"
     class TestMailer < Devise::Mailer
       def confirmation_instructions(record, token, opts = {})
         @token = token
@@ -17,4 +19,35 @@ class MailerTest < ActionMailer::TestCase
 
     assert mail.content_transfer_encoding, "7bit"
   end
+
+  # test 'correctly uses ActionMailer::Base as default parent_mailer' do
+  #   Devise.send(:remove_const, :Mailer) if defined?(Devise::Mailer)
+  #   load "#{Devise::Engine.root}/app/mailers/devise/mailer.rb"
+  #   assert Devise::Mailer.superclass == ActionMailer::Base
+  # end
+
+  # test 'correctly inherits from Devise.parent_mailer' do
+  #   class ::TestParentMailer; end
+  #   swap Devise, parent_mailer: 'TestParentMailer' do
+  #     Devise.send(:remove_const, :Mailer) if defined?(Devise::Mailer)
+  #     load "#{Devise::Engine.root}/app/mailers/devise/mailer.rb"
+  #     assert Devise::Mailer.superclass == TestParentMailer
+  #   end
+  # end
+
+  # test 'do not define Devise::Mailer when Devise.parent_mailer class is not defined' do
+  #   swap Devise, parent_mailer: 'NotDefinedParentMailer' do
+  #     Devise.send(:remove_const, :Mailer) if defined?(Devise::Mailer)
+  #     load "#{Devise::Engine.root}/app/mailers/devise/mailer.rb"
+  #     refute defined?(Devise::Mailer)
+  #   end
+  # end
+
+  # test 'defines Devise::Mailer when Devise.parent_mailer class is defined' do
+  #   swap Devise, parent_mailer: 'DefinedParentMailer' do
+  #     Devise.send(:remove_const, :Mailer) if defined?(Devise::Mailer)
+  #     load "#{Devise::Engine.root}/app/mailers/devise/mailer.rb"
+  #     assert defined?(Devise::Mailer)
+  #   end
+  # end
 end