7 files changed, 12 insertions, 19 deletions
diff --git a/actionmailer/actionmailer.gemspec b/actionmailer/actionmailer.gemspec
index e75dae6cf9..5eadd01407 100644
--- a/actionmailer/actionmailer.gemspec
+++ b/actionmailer/actionmailer.gemspec
@@ -1,4 +1,4 @@
-version = File.read(File.expand_path("../../RAILS_VERSION", __FILE__)).strip
+version = File.read(File.expand_path("../RAILS_VERSION", __dir__)).strip
 
 Gem::Specification.new do |s|
   s.platform    = Gem::Platform::RUBY
diff --git a/actionmailer/lib/action_mailer/base.rb b/actionmailer/lib/action_mailer/base.rb
index 6849f5c0f9..7133670b65 100644
--- a/actionmailer/lib/action_mailer/base.rb
+++ b/actionmailer/lib/action_mailer/base.rb
@@ -459,8 +459,7 @@ module ActionMailer
 
     helper ActionMailer::MailHelper
 
-    class_attribute :default_params
-    self.default_params = {
+    class_attribute :default_params, default: {
       mime_version: "1.0",
       charset:      "UTF-8",
       content_type: "text/plain",
diff --git a/actionmailer/lib/action_mailer/delivery_methods.rb b/actionmailer/lib/action_mailer/delivery_methods.rb
index bcc4ef03cf..afdc28aa2a 100644
--- a/actionmailer/lib/action_mailer/delivery_methods.rb
+++ b/actionmailer/lib/action_mailer/delivery_methods.rb
@@ -7,8 +7,6 @@ module ActionMailer
     extend ActiveSupport::Concern
 
     included do
-      class_attribute :delivery_methods, :delivery_method
-
       # Do not make this inheritable, because we always want it to propagate
       cattr_accessor :raise_delivery_errors
       self.raise_delivery_errors = true
@@ -19,8 +17,8 @@ module ActionMailer
       cattr_accessor :deliver_later_queue_name
       self.deliver_later_queue_name = :mailers
 
-      self.delivery_methods = {}.freeze
-      self.delivery_method  = :smtp
+      class_attribute :delivery_methods, default: {}.freeze
+      class_attribute :delivery_method, default: :smtp
 
       add_delivery_method :smtp, Mail::SMTP,
         address:              "localhost",
diff --git a/actionmailer/lib/rails/generators/mailer/mailer_generator.rb b/actionmailer/lib/rails/generators/mailer/mailer_generator.rb
index 99fe4544f1..bc21b07109 100644
--- a/actionmailer/lib/rails/generators/mailer/mailer_generator.rb
+++ b/actionmailer/lib/rails/generators/mailer/mailer_generator.rb
@@ -1,7 +1,7 @@
 module Rails
   module Generators
     class MailerGenerator < NamedBase
-      source_root File.expand_path("../templates", __FILE__)
+      source_root File.expand_path("templates", __dir__)
 
       argument :actions, type: :array, default: [], banner: "method method"
 
diff --git a/actionmailer/test/abstract_unit.rb b/actionmailer/test/abstract_unit.rb
index a646cbd581..dbfdb07e6e 100644
--- a/actionmailer/test/abstract_unit.rb
+++ b/actionmailer/test/abstract_unit.rb
@@ -9,7 +9,7 @@ end
 
 module Rails
   def self.root
-    File.expand_path("../", File.dirname(__FILE__))
+    File.expand_path("..", __dir__)
   end
 end
 
@@ -28,7 +28,7 @@ ActiveSupport::Deprecation.debug = true
 # Disable available locale checks to avoid warnings running the test suite.
 I18n.enforce_available_locales = false
 
-FIXTURE_LOAD_PATH = File.expand_path("fixtures", File.dirname(__FILE__))
+FIXTURE_LOAD_PATH = File.expand_path("fixtures", __dir__)
 ActionMailer::Base.view_paths = FIXTURE_LOAD_PATH
 
 class ActiveSupport::TestCase
diff --git a/actionmailer/test/caching_test.rb b/actionmailer/test/caching_test.rb
index cff49c8894..e76466439e 100644
--- a/actionmailer/test/caching_test.rb
+++ b/actionmailer/test/caching_test.rb
@@ -5,7 +5,7 @@ require "mailers/caching_mailer"
 
 CACHE_DIR = "test_cache"
 # Don't change '/../temp/' cavalierly or you might hose something you don't want hosed
-FILE_STORE_PATH = File.join(File.dirname(__FILE__), "/../temp/", CACHE_DIR)
+FILE_STORE_PATH = File.join(__dir__, "/../temp/", CACHE_DIR)
 
 class FragmentCachingMailer < ActionMailer::Base
   abstract!
@@ -21,10 +21,6 @@ class BaseCachingTest < ActiveSupport::TestCase
     @mailer.perform_caching = true
     @mailer.cache_store = @store
   end
-
-  def test_fragment_cache_key
-    assert_equal "views/what a key", @mailer.fragment_cache_key("what a key")
-  end
 end
 
 class FragmentCachingTest < BaseCachingTest
@@ -126,7 +122,7 @@ class FunctionalFragmentCachingTest < BaseCachingTest
 
     assert_match expected_body, email.body.encoded
     assert_match expected_body,
-      @store.read("views/caching/#{template_digest("caching_mailer/fragment_cache")}")
+      @store.read("views/caching_mailer/fragment_cache:#{template_digest("caching_mailer/fragment_cache")}/caching")
   end
 
   def test_fragment_caching_in_partials
@@ -135,7 +131,7 @@ class FunctionalFragmentCachingTest < BaseCachingTest
     assert_match(expected_body, email.body.encoded)
 
     assert_match(expected_body,
-      @store.read("views/caching/#{template_digest("caching_mailer/_partial")}"))
+      @store.read("views/caching_mailer/_partial:#{template_digest("caching_mailer/_partial")}/caching"))
   end
 
   def test_skip_fragment_cache_digesting
@@ -185,7 +181,7 @@ class FunctionalFragmentCachingTest < BaseCachingTest
     end
 
     assert_equal "caching_mailer", payload[:mailer]
-    assert_equal "views/caching/#{template_digest("caching_mailer/fragment_cache")}", payload[:key]
+    assert_equal [ :views, "caching_mailer/fragment_cache:#{template_digest("caching_mailer/fragment_cache")}", :caching ], payload[:key]
   ensure
     @mailer.enable_fragment_cache_logging = true
   end
diff --git a/actionmailer/test/log_subscriber_test.rb b/actionmailer/test/log_subscriber_test.rb
index 7969782e07..799c6144d7 100644
--- a/actionmailer/test/log_subscriber_test.rb
+++ b/actionmailer/test/log_subscriber_test.rb
@@ -36,7 +36,7 @@ class AMLogSubscriberTest < ActionMailer::TestCase
   end
 
   def test_receive_is_notified
-    fixture = File.read(File.dirname(__FILE__) + "/fixtures/raw_email")
+    fixture = File.read(File.expand_path("fixtures/raw_email", __dir__))
     TestMailer.receive(fixture)
     wait
     assert_equal(1, @logger.logged(:info).size)