Bang methods of `AR::QueryMethods` are used only internally.
We only use `left_outer_joins!`, so we can remove this alias.

Move `require "models/post"` before `require "models/comment"`

use `descendants` to get class that inherited `ActiveJob::Base`

Remove unnecessary `query_scope`

change `Class#descendants` to public API [ci skip]

`Class#descendants` has already been displayed in Rails guide,
so I think that may be displayed in doc.
http://guides.rubyonrails.org/active_support_core_extensions.html#descendants

`subclasses` get only child classes.
Therefore, if create a job common parent class as `ApplicationJob`,
inherited class does not get properly.

rename test method to avoid overriding

Remove unnecessary `count` method for collection proxy

make `fixture_file_upload` work in integration tests

Currently, `fixture_file_upload` does not work in integration test.
Because, `TestProcess` module has been include in `Session` class, but
`fixture_path` can not get from `Session` class.

Modify to include `TestProcess` in `IntegrationTest` class in order to get
correct value of `fixture_path`.

Simply use its own method because `CollectionProxy` inherits `Relation`.

Update ActiveRecord callback guide for exceptions [ci skip]

07d3d402 changed how exceptions are handled in after_commit
and after_destroy callbacks.  This commit updates the 5.0
release notes and the  ActiveRecord callback guide to reflect
the new behavior.

[ci skip]

Allow download of email attachments in the Mailer Preview template.

Remove blank else branch

Extract duplicated `create` and `create!` definition for association

Fix broken heredoc indentation caused by rubocop auto-correct

This removes the following warning.

```
./test/dispatch/routing_test.rb:3696: warning: method redefined; discarding old test_namespaced_roots
./test/dispatch/routing_test.rb:1632: warning: previous definition of test_namespaced_roots was here
```

All indentation was normalized by rubocop auto-correct at 80e66cc4.
But heredocs was still kept absolute position. This commit aligns
heredocs indentation for consistency.

add Active Job bug report templates to guide [ci skip]

Follow up to #26362

to address BasicsTest#test_readonly_attributes failure #26368

It reproduces only when both of these conditions are satisfied:

- Other test files `autosave_association_test.rb` or `where_test.rb`
  which executes `require "models/comment"` then `require "models/post"`
- When `autosave_association_test.rb` or `where_test.rb` executed before `base_test.rb`

fix class name typo in bug report templates for Active Job

Improve Getting Started [ci skip]

Added bug report templates for Active Job

Grammar fix

As demonstrated in #25880 the to_time method converts the utc time
instance to a local time instance which is an expensive operation.
Since to_datetime involves similar expensive operations we should
also cache it to speed up comparison with lots of values.

fix document for radio_button [ci skip]