3 files changed, 9 insertions, 6 deletions
diff --git a/activemodel/test/cases/attribute_assignment_test.rb b/activemodel/test/cases/attribute_assignment_test.rb
index 5ecf0a69c4..448f8587fd 100644
--- a/activemodel/test/cases/attribute_assignment_test.rb
+++ b/activemodel/test/cases/attribute_assignment_test.rb
@@ -18,10 +18,7 @@ class AttributeAssignmentTest < ActiveModel::TestCase
       raise ErrorFromAttributeWriter
     end
 
-    # TODO Change this to private once we've dropped Ruby 2.2 support.
-    # Workaround for Ruby 2.2 "private attribute?" warning.
-    protected
-
+    private
       attr_writer :metadata
   end
 
diff --git a/activemodel/test/cases/errors_test.rb b/activemodel/test/cases/errors_test.rb
index fe351f922d..cb6a8c43d5 100644
--- a/activemodel/test/cases/errors_test.rb
+++ b/activemodel/test/cases/errors_test.rb
@@ -1,7 +1,6 @@
 # frozen_string_literal: true
 
 require "cases/helper"
-require "active_support/core_ext/string/strip"
 require "yaml"
 
 class ErrorsTest < ActiveModel::TestCase
@@ -406,7 +405,7 @@ class ErrorsTest < ActiveModel::TestCase
   end
 
   test "errors are backward compatible with the Rails 4.2 format" do
-    yaml = <<-CODE.strip_heredoc
+    yaml = <<~CODE
     --- !ruby/object:ActiveModel::Errors
     base: &1 !ruby/object:ErrorsTest::Person
       errors: !ruby/object:ActiveModel::Errors
diff --git a/activemodel/test/cases/serialization_test.rb b/activemodel/test/cases/serialization_test.rb
index 9002982e7f..6826d2bbd1 100644
--- a/activemodel/test/cases/serialization_test.rb
+++ b/activemodel/test/cases/serialization_test.rb
@@ -174,4 +174,11 @@ class SerializationTest < ActiveModel::TestCase
                            { "name" => "Sue", "email" => "sue@example.com", "gender" => "female" }] }
     assert_equal expected, @user.serializable_hash(include: [{ address: { only: "street" } }, :friends])
   end
+
+  def test_all_includes_with_options
+    expected = { "email" => "david@example.com", "gender" => "male", "name" => "David",
+                "address" => { "street" => "123 Lane" },
+                "friends" => [{ "name" => "Joe" }, { "name" => "Sue" }] }
+    assert_equal expected, @user.serializable_hash(include: [address: { only: "street" }, friends: { only: "name" }])
+  end
 end