1 files changed, 10 insertions, 0 deletions
diff --git a/activemodel/test/cases/errors_test.rb b/activemodel/test/cases/errors_test.rb
index 60b20ab59f..79ccfe0c13 100644
--- a/activemodel/test/cases/errors_test.rb
+++ b/activemodel/test/cases/errors_test.rb
@@ -474,6 +474,16 @@ class ErrorsTest < ActiveModel::TestCase
     assert_equal ["name cannot be blank", "name cannot be nil"], person.errors.to_a
   end
 
+  test "to_h is deprecated" do
+    person = Person.new
+    person.errors.add(:name, "cannot be blank")
+
+    expected_deprecation = "ActiveModel::Errors#to_h is deprecated. Please call #to_hash instead."
+    assert_deprecated(expected_deprecation) do
+      assert_equal({ name: ["cannot be blank"] }, person.errors.to_h)
+    end
+  end
+
   test "to_hash returns the error messages hash" do
     person = Person.new
     person.errors.add(:name, "cannot be blank")