Abstract boolean serialization has been using 't' and 'f', with MySQL
overriding that to use 1 and 0.

This has the advantage that SQLite natively recognizes 1 and 0 as true
and false, but does not natively recognize 't' and 'f'.

This change in serialization requires a migration of stored boolean data
for SQLite databases, so it's implemented behind a configuration flag
whose default false value is deprecated. The flag itself can be
deprecated in a future version of Rails.  While loaded models will give
the correct result for boolean columns without migrating old data,
where() clauses will interact incorrectly with old data.

While working in this area, also change the abstract adapter to use
`"TRUE"` and `"FALSE"` as quoted values and `true` and `false` for
unquoted.  These are supported by PostreSQL, and MySQL remains
overriden.

Fix typo in method name

[ci skip]

Default protect from forgery

Since we now default to `protect_from_forgery with: :exception`,
provide a wrapper to `skip_before_action :verify_authenticity_token`
for disabling forgery protection.

Rather than protecting from forgery in the generated
ApplicationController, add it to ActionController::Base by config. This
configuration defaults to false to support older versions which have
removed it from their ApplicationController, but is set to true for
Rails 5.2.

Don't eagerly require Rails' minitest plugin.

By making the Rails minitest behave like a standard minitest plugin
we're much more likely to not break when people use other minitest
plugins. Like minitest-focus and pride.

To do this, we need to behave like minitest: require files up front
and then perform the plugin behavior via the at_exit hook.
This also saves us a fair bit of wrangling with test file loading.

Finally, since the environment and warnings options have to be applied
as early as possible, and since minitest loads plugins at_exit, they
have to be moved to the test command.

* Don't expect the root method.

It's likely this worked because we eagerly loaded the Rails minitest plugin
and that somehow defined a root method on `Rails`.

* Assign a backtrace to failed exceptions.

Otherwise Minitest pukes when attempting to filter the backtrace (which
Rails' backtrace cleaner then removes).

Means the exception message test has to be revised too.

This is likely caused by the rails minitest plugin now being loaded for
these tests and assigning a default backtrace cleaner.

Make sidekiq and resque integration tests work in CI

Since f55ecc6a, the integration test of sidekiq and resque is not working
in CI.
https://travis-ci.org/rails/rails/jobs/251783876

Because f55ecc6a required a password to access redis.
Therefore, handling by passing passwords when connecting to redis.

Use frozen-string-literal in ActiveJob

[ci skip] Updated language on validations.

Update MessageEncryptor example to use dynamic key length

Treat secrets as binary

Load environment file in `dbconsole` command

Prepare AP and AR to be frozen string friendly

Use frozen-string-literal in ActiveSupport

Currently the environment file is not loaded in `dbconsole` command.
Therefore, for example, if use encrypted secrets values in database.yml,
`read_encrypted_secrets` will not be true, so the value can not be
used correctly.

Fixes #29717

Until Rails 5.1.1 secrets was treated as binary inside Rails.
https://github.com/rails/rails/blob/v5.1.1/railties/lib/rails/secrets.rb#L59
https://github.com/rails/rails/blob/v5.1.1/railties/lib/rails/secrets.rb#L63

However, it is treated as String in Rails 5.1.2(changed by 157db872).
https://github.com/rails/rails/blob/v5.1.2/railties/lib/rails/secrets.rb#L104
https://github.com/rails/rails/blob/v5.1.2/railties/lib/rails/secrets.rb#L108

As a result, when upgrading from Rails 5.1.1 to 5.1.2, to write the value
treated as binary using `File.write`, causing an error.

In order to avoid `UndefinedConversionError`, fixed it to treat it as
binary like 5.1.1.
Fixes #29696

Don't allow uuids with orphan curly braces

Skip query cache for in_batches and friends

Don't translate non-database exceptions.

Fix bug with long stream identifiers when using Postgres adapter

Improve the performance of writing attributes

Add `rails secrets:show` command

Do not update `secrets.yml.enc` when secretes do not change

Use `information_schema` to extract `generation_expression` for MariaDB

Fix default `CURRENT_TIMESTAMP` in schema dumping for MariaDB 10.2

Clarify i18n guide for how pluralization rules work by default

It's possible for developers toadd a custom driver and then call it
using `driven_by`. Because we were only skipping `register` for
`:rack_test` that meant any custom driver would attempt to be registered
as well.

The three listed here are special because Rails registers them with
special options. If you're registering your own custom driver then you
don't want to separately register that driver.

Fixes #29688

Update default app files in app_generator_test

The guide misleadingly indicates that the I18n gem will apply the CLDR pluralization rules for each language. This is not the case; only the English algorithm, with support for :zero, :one, and :other, is available by default. Locale-specific pluralization rules require additional configuration and must be supplied by the application (or by another gem).