Merge pull request #25873 from schuetzm/warn_about_dirty_lock

Deprecate locking of dirty records

1 files changed, 10 insertions, 1 deletions

diff --git a/activerecord/lib/active_record/locking/pessimistic.rb b/activerecord/lib/active_record/locking/pessimistic.rb
index e73cb4fc12..263e2a5f7f 100644
--- a/activerecord/lib/active_record/locking/pessimistic.rb
+++ b/activerecord/lib/active_record/locking/pessimistic.rb
@@ -59,7 +59,16 @@ module ActiveRecord
       # or pass true for "FOR UPDATE" (the default, an exclusive row lock). Returns
       # the locked record.
       def lock!(lock = true)
-        reload(lock: lock) if persisted?
+        if persisted?
+          if changed?
+            ActiveSupport::Deprecation.warn(<<-MSG.squish)
+              Locking a record with unpersisted changes is deprecated and will raise an
+              exception in Rails 5.2. Use `save` to persist the changes, or `reload` to
+              discard them explicitly.
+            MSG
+          end
+          reload(lock: lock)
+        end
         self
       end