1 files changed, 29 insertions, 3 deletions
diff --git a/activemodel/test/cases/errors_test.rb b/activemodel/test/cases/errors_test.rb
index 605ad64e4d..e6ba06301d 100644
--- a/activemodel/test/cases/errors_test.rb
+++ b/activemodel/test/cases/errors_test.rb
@@ -1,4 +1,5 @@
 require "cases/helper"
+require "yaml"
 
 class ErrorsTest < ActiveModel::TestCase
   class Person
@@ -30,7 +31,7 @@ class ErrorsTest < ActiveModel::TestCase
   def test_delete
     errors = ActiveModel::Errors.new(self)
     errors[:foo] << "omg"
-    errors.delete(:foo)
+    errors.delete("foo")
     assert_empty errors[:foo]
   end
 
@@ -38,6 +39,7 @@ class ErrorsTest < ActiveModel::TestCase
     errors = ActiveModel::Errors.new(self)
     errors[:foo] << "omg"
     assert_includes errors, :foo, "errors should include :foo"
+    assert_includes errors, "foo", "errors should include 'foo' as :foo"
   end
 
   def test_dup
@@ -52,6 +54,7 @@ class ErrorsTest < ActiveModel::TestCase
     errors = ActiveModel::Errors.new(self)
     errors[:foo] << "omg"
     assert_equal true, errors.has_key?(:foo), "errors should have key :foo"
+    assert_equal true, errors.has_key?("foo"), "errors should have key 'foo' as :foo"
   end
 
   def test_has_no_key
@@ -63,6 +66,7 @@ class ErrorsTest < ActiveModel::TestCase
     errors = ActiveModel::Errors.new(self)
     errors[:foo] << "omg"
     assert_equal true, errors.key?(:foo), "errors should have key :foo"
+    assert_equal true, errors.key?("foo"), "errors should have key 'foo' as :foo"
   end
 
   def test_no_key
@@ -150,10 +154,11 @@ class ErrorsTest < ActiveModel::TestCase
     assert_equal ["cannot be blank"], person.errors[:name]
   end
 
-  test "added? detects if a specific error was added to the object" do
+  test "added? detects indifferent if a specific error was added to the object" do
     person = Person.new
     person.errors.add(:name, "cannot be blank")
     assert person.errors.added?(:name, "cannot be blank")
+    assert person.errors.added?("name", "cannot be blank")
   end
 
   test "added? handles symbol message" do
@@ -241,7 +246,7 @@ class ErrorsTest < ActiveModel::TestCase
     assert_equal ["name cannot be blank", "name cannot be nil"], person.errors.full_messages
   end
 
-  test "full_messages_for contains all the error messages for the given attribute" do
+  test "full_messages_for contains all the error messages for the given attribute indifferent" do
     person = Person.new
     person.errors.add(:name, "cannot be blank")
     person.errors.add(:name, "cannot be nil")
@@ -253,6 +258,7 @@ class ErrorsTest < ActiveModel::TestCase
     person.errors.add(:name, "cannot be blank")
     person.errors.add(:email, "cannot be blank")
     assert_equal ["name cannot be blank"], person.errors.full_messages_for(:name)
+    assert_equal ["name cannot be blank"], person.errors.full_messages_for("name")
   end
 
   test "full_messages_for returns an empty list in case there are no errors for the given attribute" do
@@ -360,4 +366,24 @@ class ErrorsTest < ActiveModel::TestCase
     assert_equal errors.messages, serialized.messages
     assert_equal errors.details, serialized.details
   end
+
+  test "errors are backward compatible with the Rails 4.2 format" do
+    yaml = <<-CODE.strip_heredoc
+    --- !ruby/object:ActiveModel::Errors
+    base: &1 !ruby/object:ErrorsTest::Person
+      errors: !ruby/object:ActiveModel::Errors
+        base: *1
+        messages: {}
+    messages: {}
+    CODE
+
+    errors = YAML.load(yaml)
+    errors.add(:name, :invalid)
+    assert_equal({ name: ["is invalid"] }, errors.messages)
+    assert_equal({ name: [{ error: :invalid }] }, errors.details)
+
+    errors.clear
+    assert_equal({}, errors.messages)
+    assert_equal({}, errors.details)
+  end
 end