2 files changed, 12 insertions, 18 deletions
diff --git a/activerecord/test/cases/base_test.rb b/activerecord/test/cases/base_test.rb
index 8644f2f496..e4445698dc 100644
--- a/activerecord/test/cases/base_test.rb
+++ b/activerecord/test/cases/base_test.rb
@@ -23,6 +23,8 @@ require 'models/edge'
 require 'models/joke'
 require 'models/bulb'
 require 'models/bird'
+require 'models/car'
+require 'models/bulb'
 require 'rexml/document'
 require 'active_support/core_ext/exception'
 
@@ -1442,6 +1444,16 @@ class BasicsTest < ActiveRecord::TestCase
     assert_equal "developers/#{dev.id}-#{dev.updated_at.utc.to_s(:nsec)}", dev.cache_key
   end
 
+  def test_cache_key_changes_when_child_touched
+    car = Car.create
+    Bulb.create(car: car)
+
+    key = car.cache_key
+    car.bulb.touch
+    car.reload
+    assert_not_equal key, car.cache_key
+  end
+
   def test_cache_key_format_for_existing_record_with_nil_updated_at
     dev = Developer.first
     dev.update_columns(updated_at: nil)
diff --git a/activerecord/test/cases/cache_key_test.rb b/activerecord/test/cases/cache_key_test.rb
deleted file mode 100644
index e52bbd3d30..0000000000
--- a/activerecord/test/cases/cache_key_test.rb
+++ /dev/null
@@ -1,18 +0,0 @@
-require "cases/helper"
-require "models/invoice"
-require "models/line_item"
-
-class CacheKeyTest < ActiveRecord::TestCase
-  def setup
-    @invoice = Invoice.create
-    LineItem.create(invoice: @invoice)
-    @invoice.reload
-  end
-
-  def test_cache_key_changes_when_child_touched
-    key = @invoice.cache_key
-    @invoice.line_items[0].touch
-    @invoice.reload
-    assert_not_equal key, @invoice.cache_key
-  end
-end