[Fix rubocop#658] Fix a false positive for `Rails/TransactionExitStat…

…ement`

Fixes rubocop#658.

This PR fixes a false positive for `Rails/TransactionExitStatement`
when `raise` is used in `loop` in transactions.

changelog/fix_a_false_positive_for_rails_transaction_exit_statement.md

@@ -0,0 +1 @@
+* [#658](https://github.com/rubocop/rubocop-rails/issues/658): Fix a false positive for `Rails/TransactionExitStatement` when `raise` is used in `loop` in transactions. ([@koic][])

lib/rubocop/cop/rails/transaction_exit_statement.rb

@@ -59,18 +59,26 @@ def on_send(node)
           return unless parent&.block_type?
 
           exit_statements(parent.body).each do |statement_node|
-            statement = if statement_node.return_type?
-                          'return'
-                        elsif statement_node.break_type?
-                          'break'
-                        else
-                          statement_node.method_name
-                        end
+            next unless statement_node.ancestors.find(&:block_type?).method?(:transaction)
+
+            statement = statement(statement_node)
             message = format(MSG, statement: statement)
 
             add_offense(statement_node, message: message)
           end
         end
+
+        private
+
+        def statement(statement_node)
+          if statement_node.return_type?
+            'return'
+          elsif statement_node.break_type?
+            'break'
+          else
+            statement_node.method_name
+          end
+        end
       end
     end
   end

spec/rubocop/cop/rails/transaction_exit_statement_spec.rb

@@ -43,4 +43,14 @@
       end
     RUBY
   end
+
+  it 'does not register an offense when `raise` is used in `loop` in transactions' do
+    expect_no_offenses(<<~RUBY)
+      ApplicationRecord.transaction do
+        loop do
+          break if condition
+        end
+      end
+    RUBY
+  end
 end