Merge pull request #31525 from yahonda/5-1-stable_backport_31520

Handle `FrozenError` if it is available to 5-1-stable

activerecord/test/cases/aggregations_test.rb

@@ -25,7 +25,7 @@ def test_change_single_value_object
 
   def test_immutable_value_objects
     customers(:david).balance = Money.new(100)
-    assert_raise(RuntimeError) { customers(:david).balance.instance_eval { @amount = 20 } }
+    assert_raise(frozen_error_class) { customers(:david).balance.instance_eval { @amount = 20 } }
   end
 
   def test_inferred_mapping

activerecord/test/cases/test_case.rb

@@ -63,6 +63,10 @@ def has_column?(model, column_name)
       model.reset_column_information
       model.column_names.include?(column_name.to_s)
     end
+
+    def frozen_error_class
+      Object.const_defined?(:FrozenError) ? FrozenError : RuntimeError
+    end
   end
 
   class PostgreSQLTestCase < TestCase

activerecord/test/cases/transactions_test.rb

@@ -510,11 +510,12 @@ def test_rollback_when_commit_raises
   def test_rollback_when_saving_a_frozen_record
     topic = Topic.new(:title => 'test')
     topic.freeze
-    e = assert_raise(RuntimeError) { topic.save }
-    assert_match(/frozen/i, e.message) # Not good enough, but we can't do much
-                                       # about it since there is no specific error
-                                       # for frozen objects.
-    assert !topic.persisted?, 'not persisted'
+    e = assert_raise(frozen_error_class) { topic.save }
+    # Not good enough, but we can't do much
+    # about it since there is no specific error
+    # for frozen objects.
+    assert_match(/frozen/i, e.message)
+    assert !topic.persisted?, "not persisted"
     assert_nil topic.id
     assert topic.frozen?, 'not frozen'
   end

activesupport/test/abstract_unit.rb

@@ -36,4 +36,8 @@ def jruby_skip(message = '')
 
 class ActiveSupport::TestCase
   include ActiveSupport::Testing::MethodCallAssertions
+
+  def frozen_error_class
+    Object.const_defined?(:FrozenError) ? FrozenError : RuntimeError
+  end
 end

activesupport/test/core_ext/hash_ext_test.rb

@@ -998,7 +998,7 @@ def test_except_with_original_frozen
     original.freeze
     assert_nothing_raised { original.except(:a) }
 
-    assert_raise(RuntimeError) { original.except!(:a) }
+    assert_raise(frozen_error_class) { original.except!(:a) }
   end
 
   def test_except_does_not_delete_values_in_original

railties/test/application/middleware_test.rb

@@ -216,7 +216,7 @@ def app
 
     test "can't change middleware after it's built" do
       boot!
-      assert_raise RuntimeError do
+      assert_raise frozen_error_class do
         app.config.middleware.use Rack::Config
       end
     end

railties/test/isolation/abstract_unit.rb

@@ -321,6 +321,10 @@ class ActiveSupport::TestCase
   include ActiveSupport::Testing::Stream
 
   self.test_order = :sorted
+
+  def frozen_error_class
+    Object.const_defined?(:FrozenError) ? FrozenError : RuntimeError
+  end
 end
 
 # Create a scope and build a fixture rails app