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.

10 files changed, 77 insertions, 101 deletions

diff --git a/railties/lib/rails/all.rb b/railties/lib/rails/all.rb
index f5dccd2381..b4a9c4e65f 100644
--- a/railties/lib/rails/all.rb
+++ b/railties/lib/rails/all.rb
@@ -13,8 +13,6 @@ require "rails"
   rails/test_unit/railtie
   sprockets/railtie
 ).each do |railtie|
-  begin
-    require railtie
-  rescue LoadError
-  end
+  require railtie
+rescue LoadError
 end
diff --git a/railties/lib/rails/command/behavior.rb b/railties/lib/rails/command/behavior.rb
index 718e2d9ab2..7f32b04cf1 100644
--- a/railties/lib/rails/command/behavior.rb
+++ b/railties/lib/rails/command/behavior.rb
@@ -56,12 +56,10 @@ module Rails
           def lookup!
             $LOAD_PATH.each do |base|
               Dir[File.join(base, *file_lookup_paths)].each do |path|
-                begin
-                  path = path.sub("#{base}/", "")
-                  require path
-                rescue Exception
-                  # No problem
-                end
+                path = path.sub("#{base}/", "")
+                require path
+              rescue Exception
+                # No problem
               end
             end
           end
diff --git a/railties/test/application/configuration_test.rb b/railties/test/application/configuration_test.rb
index 9fff764eca..886fb0f843 100644
--- a/railties/test/application/configuration_test.rb
+++ b/railties/test/application/configuration_test.rb
@@ -1493,14 +1493,12 @@ module ApplicationTests
     end
 
     test "config.session_store with :active_record_store with activerecord-session_store gem" do
-      begin
-        make_basic_app do |application|
-          ActionDispatch::Session::ActiveRecordStore = Class.new(ActionDispatch::Session::CookieStore)
-          application.config.session_store :active_record_store
-        end
-      ensure
-        ActionDispatch::Session.send :remove_const, :ActiveRecordStore
+      make_basic_app do |application|
+        ActionDispatch::Session::ActiveRecordStore = Class.new(ActionDispatch::Session::CookieStore)
+        application.config.session_store :active_record_store
       end
+    ensure
+      ActionDispatch::Session.send :remove_const, :ActiveRecordStore
     end
 
     test "config.session_store with :active_record_store without activerecord-session_store gem" do
diff --git a/railties/test/application/initializers/frameworks_test.rb b/railties/test/application/initializers/frameworks_test.rb
index 1530ea82d6..3cd4b8fe33 100644
--- a/railties/test/application/initializers/frameworks_test.rb
+++ b/railties/test/application/initializers/frameworks_test.rb
@@ -230,35 +230,31 @@ module ApplicationTests
     end
 
     test "active record establish_connection uses Rails.env if DATABASE_URL is not set" do
-      begin
-        require "#{app_path}/config/environment"
-        orig_database_url = ENV.delete("DATABASE_URL")
-        orig_rails_env, Rails.env = Rails.env, "development"
-        ActiveRecord::Base.establish_connection
-        assert ActiveRecord::Base.connection
-        assert_match(/#{ActiveRecord::Base.configurations[Rails.env]['database']}/, ActiveRecord::Base.connection_config[:database])
-      ensure
-        ActiveRecord::Base.remove_connection
-        ENV["DATABASE_URL"] = orig_database_url if orig_database_url
-        Rails.env = orig_rails_env if orig_rails_env
-      end
+      require "#{app_path}/config/environment"
+      orig_database_url = ENV.delete("DATABASE_URL")
+      orig_rails_env, Rails.env = Rails.env, "development"
+      ActiveRecord::Base.establish_connection
+      assert ActiveRecord::Base.connection
+      assert_match(/#{ActiveRecord::Base.configurations[Rails.env]['database']}/, ActiveRecord::Base.connection_config[:database])
+    ensure
+      ActiveRecord::Base.remove_connection
+      ENV["DATABASE_URL"] = orig_database_url if orig_database_url
+      Rails.env = orig_rails_env if orig_rails_env
     end
 
     test "active record establish_connection uses DATABASE_URL even if Rails.env is set" do
-      begin
-        require "#{app_path}/config/environment"
-        orig_database_url = ENV.delete("DATABASE_URL")
-        orig_rails_env, Rails.env = Rails.env, "development"
-        database_url_db_name = "db/database_url_db.sqlite3"
-        ENV["DATABASE_URL"] = "sqlite3:#{database_url_db_name}"
-        ActiveRecord::Base.establish_connection
-        assert ActiveRecord::Base.connection
-        assert_match(/#{database_url_db_name}/, ActiveRecord::Base.connection_config[:database])
-      ensure
-        ActiveRecord::Base.remove_connection
-        ENV["DATABASE_URL"] = orig_database_url if orig_database_url
-        Rails.env = orig_rails_env if orig_rails_env
-      end
+      require "#{app_path}/config/environment"
+      orig_database_url = ENV.delete("DATABASE_URL")
+      orig_rails_env, Rails.env = Rails.env, "development"
+      database_url_db_name = "db/database_url_db.sqlite3"
+      ENV["DATABASE_URL"] = "sqlite3:#{database_url_db_name}"
+      ActiveRecord::Base.establish_connection
+      assert ActiveRecord::Base.connection
+      assert_match(/#{database_url_db_name}/, ActiveRecord::Base.connection_config[:database])
+    ensure
+      ActiveRecord::Base.remove_connection
+      ENV["DATABASE_URL"] = orig_database_url if orig_database_url
+      Rails.env = orig_rails_env if orig_rails_env
     end
 
     test "connections checked out during initialization are returned to the pool" do
diff --git a/railties/test/application/rake/dbs_test.rb b/railties/test/application/rake/dbs_test.rb
index 039987ac8c..84ac2f057e 100644
--- a/railties/test/application/rake/dbs_test.rb
+++ b/railties/test/application/rake/dbs_test.rb
@@ -321,13 +321,12 @@ module ApplicationTests
       end
 
       test "db:setup loads schema and seeds database" do
-        begin
-          @old_rails_env = ENV["RAILS_ENV"]
-          @old_rack_env = ENV["RACK_ENV"]
-          ENV.delete "RAILS_ENV"
-          ENV.delete "RACK_ENV"
+        @old_rails_env = ENV["RAILS_ENV"]
+        @old_rack_env = ENV["RACK_ENV"]
+        ENV.delete "RAILS_ENV"
+        ENV.delete "RACK_ENV"
 
-          app_file "db/schema.rb", <<-RUBY
+        app_file "db/schema.rb", <<-RUBY
             ActiveRecord::Schema.define(version: "1") do
               create_table :users do |t|
                 t.string :name
@@ -335,16 +334,15 @@ module ApplicationTests
             end
           RUBY
 
-          app_file "db/seeds.rb", <<-RUBY
-            puts ActiveRecord::Base.connection_config[:database]
-          RUBY
+        app_file "db/seeds.rb", <<-RUBY
+          puts ActiveRecord::Base.connection_config[:database]
+        RUBY
 
-          database_path = rails("db:setup")
-          assert_equal "development.sqlite3", File.basename(database_path.strip)
-        ensure
-          ENV["RAILS_ENV"] = @old_rails_env
-          ENV["RACK_ENV"] = @old_rack_env
-        end
+        database_path = rails("db:setup")
+        assert_equal "development.sqlite3", File.basename(database_path.strip)
+      ensure
+        ENV["RAILS_ENV"] = @old_rails_env
+        ENV["RACK_ENV"] = @old_rack_env
       end
 
       test "db:setup sets ar_internal_metadata" do
diff --git a/railties/test/commands/dbconsole_test.rb b/railties/test/commands/dbconsole_test.rb
index 5e3eca6585..ce048ac527 100644
--- a/railties/test/commands/dbconsole_test.rb
+++ b/railties/test/commands/dbconsole_test.rb
@@ -308,11 +308,9 @@ class Rails::DBConsoleTest < ActiveSupport::TestCase
     def capture_abort
       @aborted = false
       @output = capture(:stderr) do
-        begin
-          yield
-        rescue SystemExit
-          @aborted = true
-        end
+        yield
+      rescue SystemExit
+        @aborted = true
       end
     end
 
diff --git a/railties/test/commands/routes_test.rb b/railties/test/commands/routes_test.rb
index 693e532c5b..9efab27b38 100644
--- a/railties/test/commands/routes_test.rb
+++ b/railties/test/commands/routes_test.rb
@@ -161,19 +161,18 @@ class Rails::Command::RoutesTest < ActiveSupport::TestCase
   end
 
   test "rails routes with expanded option" do
-    begin
-      previous_console_winsize = IO.console.winsize
-      IO.console.winsize = [0, 27]
+    previous_console_winsize = IO.console.winsize
+    IO.console.winsize = [0, 27]
 
-      app_file "config/routes.rb", <<-RUBY
+    app_file "config/routes.rb", <<-RUBY
         Rails.application.routes.draw do
           get '/cart', to: 'cart#show'
         end
       RUBY
 
-      output = run_routes_command(["--expanded"])
+    output = run_routes_command(["--expanded"])
 
-      assert_equal <<~MESSAGE, output
+    assert_equal <<~MESSAGE, output
         --[ Route 1 ]--------------
         Prefix            | cart
         Verb              | GET
@@ -205,9 +204,8 @@ class Rails::Command::RoutesTest < ActiveSupport::TestCase
         URI               | /rails/active_storage/direct_uploads(.:format)
         Controller#Action | active_storage/direct_uploads#create
       MESSAGE
-    ensure
-      IO.console.winsize = previous_console_winsize
-    end
+  ensure
+    IO.console.winsize = previous_console_winsize
   end
 
   private
diff --git a/railties/test/generators/helper_generator_test.rb b/railties/test/generators/helper_generator_test.rb
index 5d6b6f8f67..192839799e 100644
--- a/railties/test/generators/helper_generator_test.rb
+++ b/railties/test/generators/helper_generator_test.rb
@@ -30,12 +30,10 @@ class HelperGeneratorTest < Rails::Generators::TestCase
     require "#{destination_root}/app/helpers/products_helper"
 
     assert_nothing_raised do
-      begin
-        run_generator ["admin::products"]
-      ensure
-        # cleanup
-        Object.send(:remove_const, :ProductsHelper)
-      end
+      run_generator ["admin::products"]
+    ensure
+      # cleanup
+      Object.send(:remove_const, :ProductsHelper)
     end
   end
 
diff --git a/railties/test/railties/railtie_test.rb b/railties/test/railties/railtie_test.rb
index 7c3d1e3759..b9725ca0ad 100644
--- a/railties/test/railties/railtie_test.rb
+++ b/railties/test/railties/railtie_test.rb
@@ -25,12 +25,10 @@ module RailtiesTest
     end
 
     test "Railtie provides railtie_name" do
-      begin
-        class ::FooBarBaz < Rails::Railtie ; end
-        assert_equal "foo_bar_baz", FooBarBaz.railtie_name
-      ensure
-        Object.send(:remove_const, :"FooBarBaz")
-      end
+      class ::FooBarBaz < Rails::Railtie ; end
+      assert_equal "foo_bar_baz", FooBarBaz.railtie_name
+    ensure
+      Object.send(:remove_const, :"FooBarBaz")
     end
 
     test "railtie_name can be set manually" do
@@ -203,14 +201,12 @@ module RailtiesTest
     end
 
     test "we can change our environment if we want to" do
-      begin
-        original_env = Rails.env
-        Rails.env = "foo"
-        assert_equal("foo", Rails.env)
-      ensure
-        Rails.env = original_env
-        assert_equal(original_env, Rails.env)
-      end
+      original_env = Rails.env
+      Rails.env = "foo"
+      assert_equal("foo", Rails.env)
+    ensure
+      Rails.env = original_env
+      assert_equal(original_env, Rails.env)
     end
   end
 end
diff --git a/railties/test/secrets_test.rb b/railties/test/secrets_test.rb
index 06877bc76a..133d851819 100644
--- a/railties/test/secrets_test.rb
+++ b/railties/test/secrets_test.rb
@@ -35,15 +35,13 @@ class Rails::SecretsTest < ActiveSupport::TestCase
 
   test "reading with ENV variable" do
     run_secrets_generator do
-      begin
-        old_key = ENV["RAILS_MASTER_KEY"]
-        ENV["RAILS_MASTER_KEY"] = IO.binread("config/secrets.yml.key").strip
-        FileUtils.rm("config/secrets.yml.key")
-
-        assert_match "# production:\n#   external_api_key:", Rails::Secrets.read
-      ensure
-        ENV["RAILS_MASTER_KEY"] = old_key
-      end
+      old_key = ENV["RAILS_MASTER_KEY"]
+      ENV["RAILS_MASTER_KEY"] = IO.binread("config/secrets.yml.key").strip
+      FileUtils.rm("config/secrets.yml.key")
+
+      assert_match "# production:\n#   external_api_key:", Rails::Secrets.read
+    ensure
+      ENV["RAILS_MASTER_KEY"] = old_key
     end
   end