Use of ParameterFilter no longer forces `request.filtered_parameters' class to be Hash

nodoc AC::Connection::WebSocket

Fix `Relation#exists?` queries with query cache

Prevent extra `scope` construction in `find_target`

Refactor #insert_fixtures to use Arel

Deprecate an `capify!` method in generators and templates

CI against JRuby 9.1.12.0

Fix examples for `AC::Parameters#to_query` [ci skip]

Without `permit`, `AC::Parameters#to_query` raise
`AC::UnfilteredParameters`.

```ruby
params = ActionController::Parameters.new({
  name: "David",
  nationality: "Danish"
})

params.to_query
# => ActionController::UnfilteredParameters: unable to convert unpermitted parameters to hash
```

http://jruby.org/2017/06/15/jruby-9-1-12-0.html

Add a test case for #28754

Remove debug print

Because constructing `scope` is a little expensive.

The `capify` command has been removed by Capistrano 3 and became to
`cap install`.
Therefore, the `capify!` method has no meaning in Capistrano 3.
I think that should deprecate.

Ref: https://github.com/capistrano/capistrano/commit/492793916acf32ffe1604daec6fd4892c8935018

This debug print was added in 87f5e5e2 for finding the regression caused
by d314646c and the regression has already been fixed in 969339bd.

A part for JSON was splitted from #28416 as #29273 and #29273 has
already been merged.

Closes #28754.
Closes #27588.

[Ryuta Kamizono & Bradley Priest]

Fixes FIXME: rb-inotify 0.99 has been released

[ci skip] Update fedora SQLite3 package name

Remove unused defined association

Remove FK together with column in MySQL

Unlike with other databses, MySQL doesn't let you remove the column
if there's a FK on this column.

For better developer experience we want to remove the FK together with
the column.

Raise on create for singular association when parent is unpersisted

Fix `create_table` with query from relation

Don't require 'unscope' to be the same on both sides of an 'or' relation

Use nullable `id` column instead of a primary key

Users should never publicly be interacting with an instance of this.  The instance that comes along with an `AC::Connection::Base` instance (the only thing a user should be working with) is [itself intended to be private](https://github.com/tjschuck/rails/blob/master/actioncable/lib/action_cable/connection/base.rb#L137-L140).

[ci skip]

Remove references to deprecared raise_runtime_errors from documentation, which is always enabled now. Ref: https://github.com/rails/sprockets-rails/commit/655b93bffc6f51b96a7cc097f9010942693bfaae and https://github.com/rails/rails/pull/24070 . Fixes #29483 [ci skip] (#29484)

Add the `<app_root>/test` dir to the `$LOAD_PATH` as a string:

- [Rails <= 5.0](https://github.com/rails/rails/blob/5-0-stable/railties/lib/rails/commands/test.rb#L6) used to add the `<app_root>/test` as a string; this behaviour changed in rails 5.1, it's appending a `Pathname` object

Log subscriber - avoid rescuing certain exceptions

Document setting the delivery_job for ActionMailer [ci skip]

`id` column in `subscribers` was added as a primary key for ignorable in
INSERT. But it caused `NotNullViolation` for oracle-enhanced adapter.

https://github.com/rsim/oracle-enhanced/issues/1357

I changed the column to nullable to address the issue.

[ActiveModel] Improve the performance of mass assignments

Don't map id to primary key in raw_write_attribute