4 files changed, 25 insertions, 3 deletions
diff --git a/actionmailer/test/abstract_unit.rb b/actionmailer/test/abstract_unit.rb
index ae91903c95..706249a2f6 100644
--- a/actionmailer/test/abstract_unit.rb
+++ b/actionmailer/test/abstract_unit.rb
@@ -11,7 +11,6 @@ end
 require 'active_support/testing/autorun'
 require 'action_mailer'
 require 'action_mailer/test_case'
-require 'mail'
 
 # Emulate AV railtie
 require 'action_view'
diff --git a/actionmailer/test/delivery_methods_test.rb b/actionmailer/test/delivery_methods_test.rb
index 2e4e019bf7..78507ce7dc 100644
--- a/actionmailer/test/delivery_methods_test.rb
+++ b/actionmailer/test/delivery_methods_test.rb
@@ -1,5 +1,4 @@
 require 'abstract_unit'
-require 'mail'
 
 class MyCustomDelivery
 end
diff --git a/actionmailer/test/message_delivery_test.rb b/actionmailer/test/message_delivery_test.rb
index e4dd269494..862ce26187 100644
--- a/actionmailer/test/message_delivery_test.rb
+++ b/actionmailer/test/message_delivery_test.rb
@@ -2,7 +2,6 @@ require 'abstract_unit'
 require 'active_job'
 require 'minitest/mock'
 require 'mailers/delayed_mailer'
-require 'active_support/core_ext/numeric/time'
 
 class MessageDeliveryTest < ActiveSupport::TestCase
   include ActiveJob::TestHelper
@@ -10,6 +9,8 @@ class MessageDeliveryTest < ActiveSupport::TestCase
   setup do
     @previous_logger = ActiveJob::Base.logger
     @previous_delivery_method = ActionMailer::Base.delivery_method
+    @previous_deliver_later_queue_name = ActionMailer::Base.deliver_later_queue_name
+    ActionMailer::Base.deliver_later_queue_name = :test_queue
     ActionMailer::Base.delivery_method = :test
     ActiveJob::Base.logger = Logger.new(nil)
     @mail = DelayedMailer.test_message(1, 2, 3)
@@ -21,6 +22,7 @@ class MessageDeliveryTest < ActiveSupport::TestCase
   teardown do
     ActiveJob::Base.logger = @previous_logger
     ActionMailer::Base.delivery_method = @previous_delivery_method
+    ActionMailer::Base.deliver_later_queue_name = @previous_deliver_later_queue_name
   end
 
   test 'should have a message' do
@@ -81,4 +83,15 @@ class MessageDeliveryTest < ActiveSupport::TestCase
     end
   end
 
+  test 'should enqueue the job on the correct queue' do
+    assert_performed_with(job: ActionMailer::DeliveryJob, args: ['DelayedMailer', 'test_message', 'deliver_now', 1, 2, 3], queue: "test_queue") do
+      @mail.deliver_later
+    end
+  end
+
+  test 'can override the queue when enqueuing mail' do
+    assert_performed_with(job: ActionMailer::DeliveryJob, args: ['DelayedMailer', 'test_message', 'deliver_now', 1, 2, 3], queue: "another_queue") do
+      @mail.deliver_later(queue: :another_queue)
+    end
+  end
 end
diff --git a/actionmailer/test/test_helper_test.rb b/actionmailer/test/test_helper_test.rb
index 089933e245..0a4bc75d3e 100644
--- a/actionmailer/test/test_helper_test.rb
+++ b/actionmailer/test/test_helper_test.rb
@@ -112,6 +112,17 @@ class TestHelperMailerTest < ActionMailer::TestCase
     assert_match(/1 .* but 2/, error.message)
   end
 
+  def test_assert_emails_message
+    TestHelperMailer.test.deliver_now
+    error = assert_raise ActiveSupport::TestCase::Assertion do
+      assert_emails 2 do
+        TestHelperMailer.test.deliver_now
+      end
+    end
+    assert_match "Expected: 2", error.message
+    assert_match "Actual: 1", error.message
+  end
+
   def test_assert_no_emails_failure
     error = assert_raise ActiveSupport::TestCase::Assertion do
       assert_no_emails do