Enable `Style/RedundantBegin` cop to avoid newly adding redundant begin block

Currently we sometimes find a redundant begin block in code review
(e.g. https://github.com/rails/rails/pull/33604#discussion_r209784205).

I'd like to enable `Style/RedundantBegin` cop to avoid that, since
rescue/else/ensure are allowed inside do/end blocks in Ruby 2.5
(https://bugs.ruby-lang.org/issues/12906), so we'd probably meets with
that situation than before.

1 files changed, 13 insertions, 15 deletions

diff --git a/activerecord/test/cases/habtm_destroy_order_test.rb b/activerecord/test/cases/habtm_destroy_order_test.rb
index b15e1b48c4..9dbd339fe7 100644
--- a/activerecord/test/cases/habtm_destroy_order_test.rb
+++ b/activerecord/test/cases/habtm_destroy_order_test.rb
@@ -30,23 +30,21 @@ class HabtmDestroyOrderTest < ActiveRecord::TestCase
 
   test "not destroying a student with lessons leaves student<=>lesson association intact" do
     # test a normal before_destroy doesn't destroy the habtm joins
-    begin
-      sicp = Lesson.new(name: "SICP")
-      ben = Student.new(name: "Ben Bitdiddle")
-      # add a before destroy to student
-      Student.class_eval do
-        before_destroy do
-          raise ActiveRecord::Rollback unless lessons.empty?
-        end
+    sicp = Lesson.new(name: "SICP")
+    ben = Student.new(name: "Ben Bitdiddle")
+    # add a before destroy to student
+    Student.class_eval do
+      before_destroy do
+        raise ActiveRecord::Rollback unless lessons.empty?
       end
-      ben.lessons << sicp
-      ben.save!
-      ben.destroy
-      assert_not_empty ben.reload.lessons
-    ensure
-      # get rid of it so Student is still like it was
-      Student.reset_callbacks(:destroy)
     end
+    ben.lessons << sicp
+    ben.save!
+    ben.destroy
+    assert_not_empty ben.reload.lessons
+  ensure
+    # get rid of it so Student is still like it was
+    Student.reset_callbacks(:destroy)
   end
 
   test "not destroying a lesson with students leaves student<=>lesson association intact" do