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Co-authored-by: Phil Pirozhkov <[email protected]>

lib/rubocop/cop/rails/private_transaction_option.rb

@@ -25,7 +25,7 @@ module Rails
       #   ActiveRecord::Base.transaction(requires_new: true)
       #
       class PrivateTransactionOption < Base
-        MSG = 'Do not use `ActiveRecord::Base.transaction(joinable: _)`.'
+        MSG = 'Use a negated `requires_new` option instead of the internal `joinable`.'
         RESTRICT_ON_SEND = %i[transaction].freeze
 
         # @!method match_transaction_with_joinable(node)

spec/rubocop/cop/rails/private_transaction_option_spec.rb

@@ -3,14 +3,26 @@
 RSpec.describe RuboCop::Cop::Rails::PrivateTransactionOption, :config do
   it 'registers an offense when using `joinable: false`' do
     expect_offense(<<~RUBY)
-      ActiveRecord::Base.transaction(requires_new: true, joinable: false)
-                                                         ^^^^^^^^^^^^^^^ Do not use `ActiveRecord::Base.transaction(joinable: _)`.
+      ActiveRecord::Base.transaction(requires_new: true, joinable: false) do
+                                                         ^^^^^^^^^^^^^^^ Use a negated `requires_new` option instead of the internal `joinable`.
+        # ...
+      end
     RUBY
   end
 
+  it 'registers an offense when using `joinable: false`' do
+    expect_offense(<<~RUBY)
+      account.transaction(requires_new: true, joinable: false) do
+                                              ^^^^^^^^^^^^^^^ Use a negated `requires_new` option instead of the internal `joinable`.
+        # ...
+      end
+    RUBY
+  end
   it 'does not register an offense when using only `requires_new: true`' do
     expect_no_offenses(<<~RUBY)
-      ActiveRecord::Base.transaction(requires_new: true)
+      ActiveRecord::Base.transaction(requires_new: true) do
+        # ...
+      end
     RUBY
   end
 end