Remove internal without_transaction_enrollment callbacks

I've found the internal `without_transaction_enrollment` callbacks which
have not been newly used over five years, when I tried to work reverting
rails#9068 (rails#36049 (comment)).

I think that we will never make that callbacks public, since the
mechanism of `without_transaction_enrollment` is too implementation
specific, at least before rails#9068, records in a transaction had enrolled
all into the transaction.

That callbacks was introduced at rails#18936 to make `touch_later` rails#19324,
but I think that the internal callbacks is overkill to just make the
`touch_later` only, and invoking the extra callbacks also have a little
overhead even if we haven't used that.

So I think we can remove the internal callbacks for now, until we will
come up with a good use for that callbacks.

activerecord/lib/active_record/touch_later.rb

@@ -3,10 +3,9 @@
 module ActiveRecord
   # = Active Record Touch Later
   module TouchLater # :nodoc:
-    extend ActiveSupport::Concern
-
-    included do
-      before_commit_without_transaction_enrollment :touch_deferred_attributes
+    def before_committed!
+      touch_deferred_attributes if has_defer_touch_attrs? && persisted?
+      super
     end
 
     def touch_later(*names) # :nodoc:
@@ -42,11 +41,9 @@ def surreptitiously_touch(attrs)
       end
 
       def touch_deferred_attributes
-        if has_defer_touch_attrs? && persisted?
-          @_skip_dirty_tracking = true
-          touch(*@_defer_touch_attrs, time: @_touch_time)
-          @_defer_touch_attrs, @_touch_time = nil, nil
-        end
+        @_skip_dirty_tracking = true
+        touch(*@_defer_touch_attrs, time: @_touch_time)
+        @_defer_touch_attrs, @_touch_time = nil, nil
       end
 
       def has_defer_touch_attrs?

activerecord/lib/active_record/transactions.rb

@@ -10,9 +10,6 @@ module Transactions
     included do
       define_callbacks :commit, :rollback,
                        :before_commit,
-                       :before_commit_without_transaction_enrollment,
-                       :commit_without_transaction_enrollment,
-                       :rollback_without_transaction_enrollment,
                        scope: [:kind, :name]
     end
 
@@ -266,21 +263,6 @@ def after_rollback(*args, &block)
         set_callback(:rollback, :after, *args, &block)
       end
 
-      def before_commit_without_transaction_enrollment(*args, &block) # :nodoc:
-        set_options_for_callbacks!(args)
-        set_callback(:before_commit_without_transaction_enrollment, :before, *args, &block)
-      end
-
-      def after_commit_without_transaction_enrollment(*args, &block) # :nodoc:
-        set_options_for_callbacks!(args)
-        set_callback(:commit_without_transaction_enrollment, :after, *args, &block)
-      end
-
-      def after_rollback_without_transaction_enrollment(*args, &block) # :nodoc:
-        set_options_for_callbacks!(args)
-        set_callback(:rollback_without_transaction_enrollment, :after, *args, &block)
-      end
-
       private
         def set_options_for_callbacks!(args, enforced_options = {})
           options = args.extract_options!.merge!(enforced_options)
@@ -323,7 +305,6 @@ def touch(*, **) #:nodoc:
     end
 
     def before_committed! # :nodoc:
-      _run_before_commit_without_transaction_enrollment_callbacks
       _run_before_commit_callbacks
     end
 
@@ -335,7 +316,6 @@ def committed!(should_run_callbacks: true) #:nodoc:
       force_clear_transaction_record_state
       if should_run_callbacks
         @_committed_already_called = true
-        _run_commit_without_transaction_enrollment_callbacks
         _run_commit_callbacks
       end
     ensure
@@ -347,7 +327,6 @@ def committed!(should_run_callbacks: true) #:nodoc:
     def rolledback!(force_restore_state: false, should_run_callbacks: true) #:nodoc:
       if should_run_callbacks
         _run_rollback_callbacks
-        _run_rollback_without_transaction_enrollment_callbacks
       end
     ensure
       restore_transaction_record_state(force_restore_state)

activerecord/test/cases/transaction_callbacks_test.rb

@@ -719,75 +719,6 @@ def test_trigger_on_update_where_row_was_deleted
   end
 end
 
-class TransactionEnrollmentCallbacksTest < ActiveRecord::TestCase
-  class TopicWithoutTransactionalEnrollmentCallbacks < ActiveRecord::Base
-    self.table_name = :topics
-
-    before_commit_without_transaction_enrollment { |r| r.history << :before_commit }
-    after_commit_without_transaction_enrollment { |r| r.history << :after_commit }
-    after_rollback_without_transaction_enrollment { |r| r.history << :rollback }
-
-    def history
-      @history ||= []
-    end
-  end
-
-  def setup
-    @topic = TopicWithoutTransactionalEnrollmentCallbacks.create!
-  end
-
-  def test_commit_does_not_run_transactions_callbacks_without_enrollment
-    @topic.transaction do
-      @topic.content = "foo"
-      @topic.save!
-    end
-    assert_empty @topic.history
-  end
-
-  def test_commit_run_transactions_callbacks_with_explicit_enrollment
-    @topic.transaction do
-      2.times do
-        @topic.content = "foo"
-        @topic.save!
-      end
-      @topic.send(:add_to_transaction)
-    end
-    assert_equal [:before_commit, :after_commit], @topic.history
-  end
-
-  def test_commit_run_transactions_callbacks_with_nested_transactions
-    @topic.transaction do
-      @topic.transaction(requires_new: true) do
-        @topic.content = "foo"
-        @topic.save!
-        @topic.send(:add_to_transaction)
-      end
-    end
-    assert_equal [:before_commit, :after_commit], @topic.history
-  end
-
-  def test_rollback_does_not_run_transactions_callbacks_without_enrollment
-    @topic.transaction do
-      @topic.content = "foo"
-      @topic.save!
-      raise ActiveRecord::Rollback
-    end
-    assert_empty @topic.history
-  end
-
-  def test_rollback_run_transactions_callbacks_with_explicit_enrollment
-    @topic.transaction do
-      2.times do
-        @topic.content = "foo"
-        @topic.save!
-      end
-      @topic.send(:add_to_transaction)
-      raise ActiveRecord::Rollback
-    end
-    assert_equal [:rollback], @topic.history
-  end
-end
-
 class CallbacksOnActionAndConditionTest < ActiveRecord::TestCase
   self.use_transactional_tests = false