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+**DO NOT READ THIS FILE ON GITHUB, GUIDES ARE PUBLISHED ON https://guides.rubyonrails.org.**
+
+Ruby on Rails 5.0 Release Notes
+===============================
+
+Highlights in Rails 5.0:
+
+* Action Cable
+* Rails API
+* Active Record Attributes API
+* Test Runner
+* Exclusive use of `rails` CLI over Rake
+* Sprockets 3
+* Turbolinks 5
+* Ruby 2.2.2+ required
+
+These release notes cover only the major changes. To learn about various bug
+fixes and changes, please refer to the change logs or check out the [list of
+commits](https://github.com/rails/rails/commits/5-0-stable) in the main Rails
+repository on GitHub.
+
+--------------------------------------------------------------------------------
+
+Upgrading to Rails 5.0
+----------------------
+
+If you're upgrading an existing application, it's a great idea to have good test
+coverage before going in. You should also first upgrade to Rails 4.2 in case you
+haven't and make sure your application still runs as expected before attempting
+an update to Rails 5.0. A list of things to watch out for when upgrading is
+available in the
+[Upgrading Ruby on Rails](upgrading_ruby_on_rails.html#upgrading-from-rails-4-2-to-rails-5-0)
+guide.
+
+
+Major Features
+--------------
+
+### Action Cable
+
+Action Cable is a new framework in Rails 5. It seamlessly integrates
+[WebSockets](https://en.wikipedia.org/wiki/WebSocket) with the rest of your
+Rails application.
+
+Action Cable allows for real-time features to be written in Ruby in the
+same style and form as the rest of your Rails application, while still being
+performant and scalable. It's a full-stack offering that provides both a
+client-side JavaScript framework and a server-side Ruby framework. You have
+access to your full domain model written with Active Record or your ORM of
+choice.
+
+See the [Action Cable Overview](action_cable_overview.html) guide for more
+information.
+
+### API Applications
+
+Rails can now be used to create slimmed down API only applications.
+This is useful for creating and serving APIs similar to [Twitter](https://dev.twitter.com) or [GitHub](https://developer.github.com) API,
+that can be used to serve public facing, as well as, for custom applications.
+
+You can generate a new api Rails app using:
+
+```bash
+$ rails new my_api --api
+```
+
+This will do three main things:
+
+- Configure your application to start with a more limited set of middleware
+ than normal. Specifically, it will not include any middleware primarily useful
+ for browser applications (like cookies support) by default.
+- Make `ApplicationController` inherit from `ActionController::API` instead of
+ `ActionController::Base`. As with middleware, this will leave out any Action
+ Controller modules that provide functionalities primarily used by browser
+ applications.
+- Configure the generators to skip generating views, helpers, and assets when
+ you generate a new resource.
+
+The application provides a base for APIs,
+that can then be [configured to pull in functionality](api_app.html) as suitable for the application's needs.
+
+See the [Using Rails for API-only Applications](api_app.html) guide for more
+information.
+
+### Active Record attributes API
+
+Defines an attribute with a type on a model. It will override the type of existing attributes if needed.
+This allows control over how values are converted to and from SQL when assigned to a model.
+It also changes the behavior of values passed to `ActiveRecord::Base.where`, which lets use our domain objects across much of Active Record,
+without having to rely on implementation details or monkey patching.
+
+Some things that you can achieve with this:
+
+- The type detected by Active Record can be overridden.
+- A default can also be provided.
+- Attributes do not need to be backed by a database column.
+
+```ruby
+
+# db/schema.rb
+create_table :store_listings, force: true do |t|
+ t.decimal :price_in_cents
+ t.string :my_string, default: "original default"
+end
+
+# app/models/store_listing.rb
+class StoreListing < ActiveRecord::Base
+end
+
+store_listing = StoreListing.new(price_in_cents: '10.1')
+
+# before
+store_listing.price_in_cents # => BigDecimal.new(10.1)
+StoreListing.new.my_string # => "original default"
+
+class StoreListing < ActiveRecord::Base
+ attribute :price_in_cents, :integer # custom type
+ attribute :my_string, :string, default: "new default" # default value
+ attribute :my_default_proc, :datetime, default: -> { Time.now } # default value
+ attribute :field_without_db_column, :integer, array: true
+end
+
+# after
+store_listing.price_in_cents # => 10
+StoreListing.new.my_string # => "new default"
+StoreListing.new.my_default_proc # => 2015-05-30 11:04:48 -0600
+model = StoreListing.new(field_without_db_column: ["1", "2", "3"])
+model.attributes # => {field_without_db_column: [1, 2, 3]}
+```
+
+**Creating Custom Types:**
+
+You can define your own custom types, as long as they respond
+to the methods defined on the value type. The method `deserialize` or
+`cast` will be called on your type object, with raw input from the
+database or from your controllers. This is useful, for example, when doing custom conversion,
+like Money data.
+
+**Querying:**
+
+When `ActiveRecord::Base.where` is called, it will
+use the type defined by the model class to convert the value to SQL,
+calling `serialize` on your type object.
+
+This gives the objects ability to specify, how to convert values when performing SQL queries.
+
+**Dirty Tracking:**
+
+The type of an attribute is given the opportunity to change how dirty
+tracking is performed.
+
+See its
+[documentation](http://api.rubyonrails.org/v5.0.1/classes/ActiveRecord/Attributes/ClassMethods.html)
+for a detailed write up.
+
+
+### Test Runner
+
+A new test runner has been introduced to enhance the capabilities of running tests from Rails.
+To use this test runner simply type `bin/rails test`.
+
+Test Runner is inspired from `RSpec`, `minitest-reporters`, `maxitest` and others.
+It includes some of these notable advancements:
+
+- Run a single test using line number of test.
+- Run multiple tests pinpointing to line number of tests.
+- Improved failure messages, which also add ease of re-running failed tests.
+- Fail fast using `-f` option, to stop tests immediately on occurrence of failure,
+instead of waiting for the suite to complete.
+- Defer test output until the end of a full test run using the `-d` option.
+- Complete exception backtrace output using `-b` option.
+- Integration with minitest to allow options like `-s` for test seed data,
+`-n` for running specific test by name, `-v` for better verbose output and so forth.
+- Colored test output.
+
+Railties
+--------
+
+Please refer to the [Changelog][railties] for detailed changes.
+
+### Removals
+
+* Removed debugger support, use byebug instead. `debugger` is not supported by
+ Ruby
+ 2.2. ([commit](https://github.com/rails/rails/commit/93559da4826546d07014f8cfa399b64b4a143127))
+
+* Removed deprecated `test:all` and `test:all:db` tasks.
+ ([commit](https://github.com/rails/rails/commit/f663132eef0e5d96bf2a58cec9f7c856db20be7c))
+
+* Removed deprecated `Rails::Rack::LogTailer`.
+ ([commit](https://github.com/rails/rails/commit/c564dcb75c191ab3d21cc6f920998b0d6fbca623))
+
+* Removed deprecated `RAILS_CACHE` constant.
+ ([commit](https://github.com/rails/rails/commit/b7f856ce488ef8f6bf4c12bb549f462cb7671c08))
+
+* Removed deprecated `serve_static_assets` configuration.
+ ([commit](https://github.com/rails/rails/commit/463b5d7581ee16bfaddf34ca349b7d1b5878097c))
+
+* Removed the documentation tasks `doc:app`, `doc:rails`, and `doc:guides`.
+ ([commit](https://github.com/rails/rails/commit/cd7cc5254b090ccbb84dcee4408a5acede25ef2a))
+
+* Removed `Rack::ContentLength` middleware from the default
+ stack. ([Commit](https://github.com/rails/rails/commit/56903585a099ab67a7acfaaef0a02db8fe80c450))
+
+### Deprecations
+
+* Deprecated `config.static_cache_control` in favor of
+ `config.public_file_server.headers`.
+ ([Pull Request](https://github.com/rails/rails/pull/19135))
+
+* Deprecated `config.serve_static_files` in favor of `config.public_file_server.enabled`.
+ ([Pull Request](https://github.com/rails/rails/pull/22173))
+
+* Deprecated the tasks in the `rails` task namespace in favor of the `app` namespace.
+ (e.g. `rails:update` and `rails:template` tasks are renamed to `app:update` and `app:template`.)
+ ([Pull Request](https://github.com/rails/rails/pull/23439))
+
+### Notable changes
+
+* Added Rails test runner `bin/rails test`.
+ ([Pull Request](https://github.com/rails/rails/pull/19216))
+
+* Newly generated applications and plugins get a `README.md` in Markdown.
+ ([commit](https://github.com/rails/rails/commit/89a12c931b1f00b90e74afffcdc2fc21f14ca663),
+ [Pull Request](https://github.com/rails/rails/pull/22068))
+
+* Added `bin/rails restart` task to restart your Rails app by touching `tmp/restart.txt`.
+ ([Pull Request](https://github.com/rails/rails/pull/18965))
+
+* Added `bin/rails initializers` task to print out all defined initializers in
+ the order they are invoked by Rails.
+ ([Pull Request](https://github.com/rails/rails/pull/19323))
+
+* Added `bin/rails dev:cache` to enable or disable caching in development mode.
+ ([Pull Request](https://github.com/rails/rails/pull/20961))
+
+* Added `bin/update` script to update the development environment automatically.
+ ([Pull Request](https://github.com/rails/rails/pull/20972))
+
+* Proxy Rake tasks through `bin/rails`.
+ ([Pull Request](https://github.com/rails/rails/pull/22457),
+ [Pull Request](https://github.com/rails/rails/pull/22288))
+
+* New applications are generated with the evented file system monitor enabled
+ on Linux and macOS. The feature can be opted out by passing
+ `--skip-listen` to the generator.
+ ([commit](https://github.com/rails/rails/commit/de6ad5665d2679944a9ee9407826ba88395a1003),
+ [commit](https://github.com/rails/rails/commit/94dbc48887bf39c241ee2ce1741ee680d773f202))
+
+* Generate applications with an option to log to STDOUT in production
+ using the environment variable `RAILS_LOG_TO_STDOUT`.
+ ([Pull Request](https://github.com/rails/rails/pull/23734))
+
+* Enable HSTS with IncludeSudomains header for new applications.
+ ([Pull Request](https://github.com/rails/rails/pull/23852))
+
+* The application generator writes a new file `config/spring.rb`, which tells
+ Spring to watch additional common files.
+ ([commit](https://github.com/rails/rails/commit/b04d07337fd7bc17e88500e9d6bcd361885a45f8))
+
+* Added `--skip-action-mailer` to skip Action Mailer while generating new app.
+ ([Pull Request](https://github.com/rails/rails/pull/18288))
+
+* Removed `tmp/sessions` directory and the clear rake task associated with it.
+ ([Pull Request](https://github.com/rails/rails/pull/18314))
+
+* Changed `_form.html.erb` generated by scaffold generator to use local variables.
+ ([Pull Request](https://github.com/rails/rails/pull/13434))
+
+* Disabled autoloading of classes in production environment.
+ ([commit](https://github.com/rails/rails/commit/a71350cae0082193ad8c66d65ab62e8bb0b7853b))
+
+Action Pack
+-----------
+
+Please refer to the [Changelog][action-pack] for detailed changes.
+
+### Removals
+
+* Removed `ActionDispatch::Request::Utils.deep_munge`.
+ ([commit](https://github.com/rails/rails/commit/52cf1a71b393486435fab4386a8663b146608996))
+
+* Removed `ActionController::HideActions`.
+ ([Pull Request](https://github.com/rails/rails/pull/18371))
+
+* Removed `respond_to` and `respond_with` placeholder methods, this functionality
+ has been extracted to the
+ [responders](https://github.com/plataformatec/responders) gem.
+ ([commit](https://github.com/rails/rails/commit/afd5e9a7ff0072e482b0b0e8e238d21b070b6280))
+
+* Removed deprecated assertion files.
+ ([commit](https://github.com/rails/rails/commit/92e27d30d8112962ee068f7b14aa7b10daf0c976))
+
+* Removed deprecated usage of string keys in URL helpers.
+ ([commit](https://github.com/rails/rails/commit/34e380764edede47f7ebe0c7671d6f9c9dc7e809))
+
+* Removed deprecated `only_path` option on `*_path` helpers.
+ ([commit](https://github.com/rails/rails/commit/e4e1fd7ade47771067177254cb133564a3422b8a))
+
+* Removed deprecated `NamedRouteCollection#helpers`.
+ ([commit](https://github.com/rails/rails/commit/2cc91c37bc2e32b7a04b2d782fb8f4a69a14503f))
+
+* Removed deprecated support to define routes with `:to` option that doesn't contain `#`.
+ ([commit](https://github.com/rails/rails/commit/1f3b0a8609c00278b9a10076040ac9c90a9cc4a6))
+
+* Removed deprecated `ActionDispatch::Response#to_ary`.
+ ([commit](https://github.com/rails/rails/commit/4b19d5b7bcdf4f11bd1e2e9ed2149a958e338c01))
+
+* Removed deprecated `ActionDispatch::Request#deep_munge`.
+ ([commit](https://github.com/rails/rails/commit/7676659633057dacd97b8da66e0d9119809b343e))
+
+* Removed deprecated
+ `ActionDispatch::Http::Parameters#symbolized_path_parameters`.
+ ([commit](https://github.com/rails/rails/commit/7fe7973cd8bd119b724d72c5f617cf94c18edf9e))
+
+* Removed deprecated option `use_route` in controller tests.
+ ([commit](https://github.com/rails/rails/commit/e4cfd353a47369dd32198b0e67b8cbb2f9a1c548))
+
+* Removed `assigns` and `assert_template`. Both methods have been extracted
+ into the
+ [rails-controller-testing](https://github.com/rails/rails-controller-testing)
+ gem.
+ ([Pull Request](https://github.com/rails/rails/pull/20138))
+
+### Deprecations
+
+* Deprecated all `*_filter` callbacks in favor of `*_action` callbacks.
+ ([Pull Request](https://github.com/rails/rails/pull/18410))
+
+* Deprecated `*_via_redirect` integration test methods. Use `follow_redirect!`
+ manually after the request call for the same behavior.
+ ([Pull Request](https://github.com/rails/rails/pull/18693))
+
+* Deprecated `AbstractController#skip_action_callback` in favor of individual
+ skip_callback methods.
+ ([Pull Request](https://github.com/rails/rails/pull/19060))
+
+* Deprecated `:nothing` option for `render` method.
+ ([Pull Request](https://github.com/rails/rails/pull/20336))
+
+* Deprecated passing first parameter as `Hash` and default status code for
+ `head` method.
+ ([Pull Request](https://github.com/rails/rails/pull/20407))
+
+* Deprecated using strings or symbols for middleware class names. Use class
+ names instead.
+ ([commit](https://github.com/rails/rails/commit/83b767ce))
+
+* Deprecated accessing mime types via constants (eg. `Mime::HTML`). Use the
+ subscript operator with a symbol instead (eg. `Mime[:html]`).
+ ([Pull Request](https://github.com/rails/rails/pull/21869))
+
+* Deprecated `redirect_to :back` in favor of `redirect_back`, which accepts a
+ required `fallback_location` argument, thus eliminating the possibility of a
+ `RedirectBackError`.
+ ([Pull Request](https://github.com/rails/rails/pull/22506))
+
+* `ActionDispatch::IntegrationTest` and `ActionController::TestCase` deprecate positional arguments in favor of
+ keyword arguments. ([Pull Request](https://github.com/rails/rails/pull/18323))
+
+* Deprecated `:controller` and `:action` path parameters.
+ ([Pull Request](https://github.com/rails/rails/pull/23980))
+
+* Deprecated env method on controller instances.
+ ([commit](https://github.com/rails/rails/commit/05934d24aff62d66fc62621aa38dae6456e276be))
+
+* `ActionDispatch::ParamsParser` is deprecated and was removed from the
+ middleware stack. To configure the parameter parsers use
+ `ActionDispatch::Request.parameter_parsers=`.
+ ([commit](https://github.com/rails/rails/commit/38d2bf5fd1f3e014f2397898d371c339baa627b1),
+ [commit](https://github.com/rails/rails/commit/5ed38014811d4ce6d6f957510b9153938370173b))
+
+### Notable changes
+
+* Added `ActionController::Renderer` to render arbitrary templates
+ outside controller actions.
+ ([Pull Request](https://github.com/rails/rails/pull/18546))
+
+* Migrating to keyword arguments syntax in `ActionController::TestCase` and
+ `ActionDispatch::Integration` HTTP request methods.
+ ([Pull Request](https://github.com/rails/rails/pull/18323))
+
+* Added `http_cache_forever` to Action Controller, so we can cache a response
+ that never gets expired.
+ ([Pull Request](https://github.com/rails/rails/pull/18394))
+
+* Provide friendlier access to request variants.
+ ([Pull Request](https://github.com/rails/rails/pull/18939))
+
+* For actions with no corresponding templates, render `head :no_content`
+ instead of raising an error.
+ ([Pull Request](https://github.com/rails/rails/pull/19377))
+
+* Added the ability to override default form builder for a controller.
+ ([Pull Request](https://github.com/rails/rails/pull/19736))
+
+* Added support for API only apps.
+ `ActionController::API` is added as a replacement of
+ `ActionController::Base` for this kind of applications.
+ ([Pull Request](https://github.com/rails/rails/pull/19832))
+
+* Make `ActionController::Parameters` no longer inherits from
+ `HashWithIndifferentAccess`.
+ ([Pull Request](https://github.com/rails/rails/pull/20868))
+
+* Make it easier to opt in to `config.force_ssl` and `config.ssl_options` by
+ making them less dangerous to try and easier to disable.
+ ([Pull Request](https://github.com/rails/rails/pull/21520))
+
+* Added the ability of returning arbitrary headers to `ActionDispatch::Static`.
+ ([Pull Request](https://github.com/rails/rails/pull/19135))
+
+* Changed the `protect_from_forgery` prepend default to `false`.
+ ([commit](https://github.com/rails/rails/commit/39794037817703575c35a75f1961b01b83791191))
+
+* `ActionController::TestCase` will be moved to its own gem in Rails 5.1. Use
+ `ActionDispatch::IntegrationTest` instead.
+ ([commit](https://github.com/rails/rails/commit/4414c5d1795e815b102571425974a8b1d46d932d))
+
+* Rails generates weak ETags by default.
+ ([Pull Request](https://github.com/rails/rails/pull/17573))
+
+* Controller actions without an explicit `render` call and with no
+ corresponding templates will render `head :no_content` implicitly
+ instead of raising an error.
+ (Pull Request [1](https://github.com/rails/rails/pull/19377),
+ [2](https://github.com/rails/rails/pull/23827))
+
+* Added an option for per-form CSRF tokens.
+ ([Pull Request](https://github.com/rails/rails/pull/22275))
+
+* Added request encoding and response parsing to integration tests.
+ ([Pull Request](https://github.com/rails/rails/pull/21671))
+
+* Add `ActionController#helpers` to get access to the view context
+ at the controller level.
+ ([Pull Request](https://github.com/rails/rails/pull/24866))
+
+* Discarded flash messages get removed before storing into session.
+ ([Pull Request](https://github.com/rails/rails/pull/18721))
+
+* Added support for passing collection of records to `fresh_when` and
+ `stale?`.
+ ([Pull Request](https://github.com/rails/rails/pull/18374))
+
+* `ActionController::Live` became an `ActiveSupport::Concern`. That
+ means it can't be just included in other modules without extending
+ them with `ActiveSupport::Concern` or `ActionController::Live`
+ won't take effect in production. Some people may be using another
+ module to include some special `Warden`/`Devise` authentication
+ failure handling code as well since the middleware can't catch a
+ `:warden` thrown by a spawned thread which is the case when using
+ `ActionController::Live`.
+ ([More details in this issue](https://github.com/rails/rails/issues/25581))
+
+* Introduce `Response#strong_etag=` and `#weak_etag=` and analogous
+ options for `fresh_when` and `stale?`.
+ ([Pull Request](https://github.com/rails/rails/pull/24387))
+
+Action View
+-------------
+
+Please refer to the [Changelog][action-view] for detailed changes.
+
+### Removals
+
+* Removed deprecated `AbstractController::Base::parent_prefixes`.
+ ([commit](https://github.com/rails/rails/commit/34bcbcf35701ca44be559ff391535c0dd865c333))
+
+* Removed `ActionView::Helpers::RecordTagHelper`, this functionality
+ has been extracted to the
+ [record_tag_helper](https://github.com/rails/record_tag_helper) gem.
+ ([Pull Request](https://github.com/rails/rails/pull/18411))
+
+* Removed `:rescue_format` option for `translate` helper since it's no longer
+ supported by I18n.
+ ([Pull Request](https://github.com/rails/rails/pull/20019))
+
+### Notable Changes
+
+* Changed the default template handler from `ERB` to `Raw`.
+ ([commit](https://github.com/rails/rails/commit/4be859f0fdf7b3059a28d03c279f03f5938efc80))
+
+* Collection rendering can cache and fetches multiple partials at once.
+ ([Pull Request](https://github.com/rails/rails/pull/18948),
+ [commit](https://github.com/rails/rails/commit/e93f0f0f133717f9b06b1eaefd3442bd0ff43985))
+
+* Added wildcard matching to explicit dependencies.
+ ([Pull Request](https://github.com/rails/rails/pull/20904))
+
+* Make `disable_with` the default behavior for submit tags. Disables the
+ button on submit to prevent double submits.
+ ([Pull Request](https://github.com/rails/rails/pull/21135))
+
+* Partial template name no longer has to be a valid Ruby identifier.
+ ([commit](https://github.com/rails/rails/commit/da9038e))
+
+* The `datetime_tag` helper now generates an input tag with the type of
+ `datetime-local`.
+ ([Pull Request](https://github.com/rails/rails/pull/25469))
+
+* Allow blocks while rendering with the `render partial:` helper.
+ ([Pull Request](https://github.com/rails/rails/pull/17974))
+
+Action Mailer
+-------------
+
+Please refer to the [Changelog][action-mailer] for detailed changes.
+
+### Removals
+
+* Removed deprecated `*_path` helpers in email views.
+ ([commit](https://github.com/rails/rails/commit/d282125a18c1697a9b5bb775628a2db239142ac7))
+
+* Removed deprecated `deliver` and `deliver!` methods.
+ ([commit](https://github.com/rails/rails/commit/755dcd0691f74079c24196135f89b917062b0715))
+
+### Notable changes
+
+* Template lookup now respects default locale and I18n fallbacks.
+ ([commit](https://github.com/rails/rails/commit/ecb1981b))
+
+* Added `_mailer` suffix to mailers created via generator, following the same
+ naming convention used in controllers and jobs.
+ ([Pull Request](https://github.com/rails/rails/pull/18074))
+
+* Added `assert_enqueued_emails` and `assert_no_enqueued_emails`.
+ ([Pull Request](https://github.com/rails/rails/pull/18403))
+
+* Added `config.action_mailer.deliver_later_queue_name` configuration to set
+ the mailer queue name.
+ ([Pull Request](https://github.com/rails/rails/pull/18587))
+
+* Added support for fragment caching in Action Mailer views.
+ Added new config option `config.action_mailer.perform_caching` to determine
+ whether your templates should perform caching or not.
+ ([Pull Request](https://github.com/rails/rails/pull/22825))
+
+
+Active Record
+-------------
+
+Please refer to the [Changelog][active-record] for detailed changes.
+
+### Removals
+
+* Removed deprecated behavior allowing nested arrays to be passed as query
+ values. ([Pull Request](https://github.com/rails/rails/pull/17919))
+
+* Removed deprecated `ActiveRecord::Tasks::DatabaseTasks#load_schema`. This
+ method was replaced by `ActiveRecord::Tasks::DatabaseTasks#load_schema_for`.
+ ([commit](https://github.com/rails/rails/commit/ad783136d747f73329350b9bb5a5e17c8f8800da))
+
+* Removed deprecated `serialized_attributes`.
+ ([commit](https://github.com/rails/rails/commit/82043ab53cb186d59b1b3be06122861758f814b2))
+
+* Removed deprecated automatic counter caches on `has_many :through`.
+ ([commit](https://github.com/rails/rails/commit/87c8ce340c6c83342df988df247e9035393ed7a0))
+
+* Removed deprecated `sanitize_sql_hash_for_conditions`.
+ ([commit](https://github.com/rails/rails/commit/3a59dd212315ebb9bae8338b98af259ac00bbef3))
+
+* Removed deprecated `Reflection#source_macro`.
+ ([commit](https://github.com/rails/rails/commit/ede8c199a85cfbb6457d5630ec1e285e5ec49313))
+
+* Removed deprecated `symbolized_base_class` and `symbolized_sti_name`.
+ ([commit](https://github.com/rails/rails/commit/9013e28e52eba3a6ffcede26f85df48d264b8951))
+
+* Removed deprecated `ActiveRecord::Base.disable_implicit_join_references=`.
+ ([commit](https://github.com/rails/rails/commit/0fbd1fc888ffb8cbe1191193bf86933110693dfc))
+
+* Removed deprecated access to connection specification using a string accessor.
+ ([commit](https://github.com/rails/rails/commit/efdc20f36ccc37afbb2705eb9acca76dd8aabd4f))
+
+* Removed deprecated support to preload instance-dependent associations.
+ ([commit](https://github.com/rails/rails/commit/4ed97979d14c5e92eb212b1a629da0a214084078))
+
+* Removed deprecated support for PostgreSQL ranges with exclusive lower bounds.
+ ([commit](https://github.com/rails/rails/commit/a076256d63f64d194b8f634890527a5ed2651115))
+
+* Removed deprecation when modifying a relation with cached Arel.
+ This raises an `ImmutableRelation` error instead.
+ ([commit](https://github.com/rails/rails/commit/3ae98181433dda1b5e19910e107494762512a86c))
+
+* Removed `ActiveRecord::Serialization::XmlSerializer` from core. This feature
+ has been extracted into the
+ [activemodel-serializers-xml](https://github.com/rails/activemodel-serializers-xml)
+ gem. ([Pull Request](https://github.com/rails/rails/pull/21161))
+
+* Removed support for the legacy `mysql` database adapter from core. Most users should
+ be able to use `mysql2`. It will be converted to a separate gem when we find someone
+ to maintain it. ([Pull Request 1](https://github.com/rails/rails/pull/22642),
+ [Pull Request 2](https://github.com/rails/rails/pull/22715))
+
+* Removed support for the `protected_attributes` gem.
+ ([commit](https://github.com/rails/rails/commit/f4fbc0301021f13ae05c8e941c8efc4ae351fdf9))
+
+* Removed support for PostgreSQL versions below 9.1.
+ ([Pull Request](https://github.com/rails/rails/pull/23434))
+
+* Removed support for `activerecord-deprecated_finders` gem.
+ ([commit](https://github.com/rails/rails/commit/78dab2a8569408658542e462a957ea5a35aa4679))
+
+* Removed `ActiveRecord::ConnectionAdapters::Column::TRUE_VALUES` constant.
+ ([commit](https://github.com/rails/rails/commit/a502703c3d2151d4d3b421b29fefdac5ad05df61))
+
+### Deprecations
+
+* Deprecated passing a class as a value in a query. Users should pass strings
+ instead. ([Pull Request](https://github.com/rails/rails/pull/17916))
+
+* Deprecated returning `false` as a way to halt Active Record callback
+ chains. The recommended way is to
+ `throw(:abort)`. ([Pull Request](https://github.com/rails/rails/pull/17227))
+
+* Deprecated `ActiveRecord::Base.errors_in_transactional_callbacks=`.
+ ([commit](https://github.com/rails/rails/commit/07d3d402341e81ada0214f2cb2be1da69eadfe72))
+
+* Deprecated `Relation#uniq` use `Relation#distinct` instead.
+ ([commit](https://github.com/rails/rails/commit/adfab2dcf4003ca564d78d4425566dd2d9cd8b4f))
+
+* Deprecated the PostgreSQL `:point` type in favor of a new one which will return
+ `Point` objects instead of an `Array`
+ ([Pull Request](https://github.com/rails/rails/pull/20448))
+
+* Deprecated force association reload by passing a truthy argument to
+ association method.
+ ([Pull Request](https://github.com/rails/rails/pull/20888))
+
+* Deprecated the keys for association `restrict_dependent_destroy` errors in favor
+ of new key names.
+ ([Pull Request](https://github.com/rails/rails/pull/20668))
+
+* Synchronize behavior of `#tables`.
+ ([Pull Request](https://github.com/rails/rails/pull/21601))
+
+* Deprecated `SchemaCache#tables`, `SchemaCache#table_exists?` and
+ `SchemaCache#clear_table_cache!` in favor of their new data source
+ counterparts.
+ ([Pull Request](https://github.com/rails/rails/pull/21715))
+
+* Deprecated `connection.tables` on the SQLite3 and MySQL adapters.
+ ([Pull Request](https://github.com/rails/rails/pull/21601))
+
+* Deprecated passing arguments to `#tables` - the `#tables` method of some
+ adapters (mysql2, sqlite3) would return both tables and views while others
+ (postgresql) just return tables. To make their behavior consistent,
+ `#tables` will return only tables in the future.
+ ([Pull Request](https://github.com/rails/rails/pull/21601))
+
+* Deprecated `table_exists?` - The `#table_exists?` method would check both
+ tables and views. To make their behavior consistent with `#tables`,
+ `#table_exists?` will check only tables in the future.
+ ([Pull Request](https://github.com/rails/rails/pull/21601))
+
+* Deprecate sending the `offset` argument to `find_nth`. Please use the
+ `offset` method on relation instead.
+ ([Pull Request](https://github.com/rails/rails/pull/22053))
+
+* Deprecated `{insert|update|delete}_sql` in `DatabaseStatements`.
+ Use the `{insert|update|delete}` public methods instead.
+ ([Pull Request](https://github.com/rails/rails/pull/23086))
+
+* Deprecated `use_transactional_fixtures` in favor of
+ `use_transactional_tests` for more clarity.
+ ([Pull Request](https://github.com/rails/rails/pull/19282))
+
+* Deprecated passing a column to `ActiveRecord::Connection#quote`.
+ ([commit](https://github.com/rails/rails/commit/7bb620869725ad6de603f6a5393ee17df13aa96c))
+
+* Added an option `end` to `find_in_batches` that complements the `start`
+ parameter to specify where to stop batch processing.
+ ([Pull Request](https://github.com/rails/rails/pull/12257))
+
+
+### Notable changes
+
+* Added a `foreign_key` option to `references` while creating the table.
+ ([commit](https://github.com/rails/rails/commit/99a6f9e60ea55924b44f894a16f8de0162cf2702))
+
+* New attributes
+ API. ([commit](https://github.com/rails/rails/commit/8c752c7ac739d5a86d4136ab1e9d0142c4041e58))
+
+* Added `:_prefix`/`:_suffix` option to `enum` definition.
+ ([Pull Request](https://github.com/rails/rails/pull/19813),
+ [Pull Request](https://github.com/rails/rails/pull/20999))
+
+* Added `#cache_key` to `ActiveRecord::Relation`.
+ ([Pull Request](https://github.com/rails/rails/pull/20884))
+
+* Changed the default `null` value for `timestamps` to `false`.
+ ([commit](https://github.com/rails/rails/commit/a939506f297b667291480f26fa32a373a18ae06a))
+
+* Added `ActiveRecord::SecureToken` in order to encapsulate generation of
+ unique tokens for attributes in a model using `SecureRandom`.
+ ([Pull Request](https://github.com/rails/rails/pull/18217))
+
+* Added `:if_exists` option for `drop_table`.
+ ([Pull Request](https://github.com/rails/rails/pull/18597))
+
+* Added `ActiveRecord::Base#accessed_fields`, which can be used to quickly
+ discover which fields were read from a model when you are looking to only
+ select the data you need from the database.
+ ([commit](https://github.com/rails/rails/commit/be9b68038e83a617eb38c26147659162e4ac3d2c))
+
+* Added the `#or` method on `ActiveRecord::Relation`, allowing use of the OR
+ operator to combine WHERE or HAVING clauses.
+ ([commit](https://github.com/rails/rails/commit/b0b37942d729b6bdcd2e3178eda7fa1de203b3d0))
+
+* Added `ActiveRecord::Base.suppress` to prevent the receiver from being saved
+ during the given block.
+ ([Pull Request](https://github.com/rails/rails/pull/18910))
+
+* `belongs_to` will now trigger a validation error by default if the
+ association is not present. You can turn this off on a per-association basis
+ with `optional: true`. Also deprecate `required` option in favor of `optional`
+ for `belongs_to`.
+ ([Pull Request](https://github.com/rails/rails/pull/18937))
+
+* Added `config.active_record.dump_schemas` to configure the behavior of
+ `db:structure:dump`.
+ ([Pull Request](https://github.com/rails/rails/pull/19347))
+
+* Added `config.active_record.warn_on_records_fetched_greater_than` option.
+ ([Pull Request](https://github.com/rails/rails/pull/18846))
+
+* Added a native JSON data type support in MySQL.
+ ([Pull Request](https://github.com/rails/rails/pull/21110))
+
+* Added support for dropping indexes concurrently in PostgreSQL.
+ ([Pull Request](https://github.com/rails/rails/pull/21317))
+
+* Added `#views` and `#view_exists?` methods on connection adapters.
+ ([Pull Request](https://github.com/rails/rails/pull/21609))
+
+* Added `ActiveRecord::Base.ignored_columns` to make some columns
+ invisible from Active Record.
+ ([Pull Request](https://github.com/rails/rails/pull/21720))
+
+* Added `connection.data_sources` and `connection.data_source_exists?`.
+ These methods determine what relations can be used to back Active Record
+ models (usually tables and views).
+ ([Pull Request](https://github.com/rails/rails/pull/21715))
+
+* Allow fixtures files to set the model class in the YAML file itself.
+ ([Pull Request](https://github.com/rails/rails/pull/20574))
+
+* Added ability to default to `uuid` as primary key when generating database
+ migrations. ([Pull Request](https://github.com/rails/rails/pull/21762))
+
+* Added `ActiveRecord::Relation#left_joins` and
+ `ActiveRecord::Relation#left_outer_joins`.
+ ([Pull Request](https://github.com/rails/rails/pull/12071))
+
+* Added `after_{create,update,delete}_commit` callbacks.
+ ([Pull Request](https://github.com/rails/rails/pull/22516))
+
+* Version the API presented to migration classes, so we can change parameter
+ defaults without breaking existing migrations, or forcing them to be
+ rewritten through a deprecation cycle.
+ ([Pull Request](https://github.com/rails/rails/pull/21538))
+
+* `ApplicationRecord` is a new superclass for all app models, analogous to app
+ controllers subclassing `ApplicationController` instead of
+ `ActionController::Base`. This gives apps a single spot to configure app-wide
+ model behavior.
+ ([Pull Request](https://github.com/rails/rails/pull/22567))
+
+* Added ActiveRecord `#second_to_last` and `#third_to_last` methods.
+ ([Pull Request](https://github.com/rails/rails/pull/23583))
+
+* Added ability to annotate database objects (tables, columns, indexes)
+ with comments stored in database metadata for PostgreSQL & MySQL.
+ ([Pull Request](https://github.com/rails/rails/pull/22911))
+
+* Added prepared statements support to `mysql2` adapter, for mysql2 0.4.4+,
+ Previously this was only supported on the deprecated `mysql` legacy adapter.
+ To enable, set `prepared_statements: true` in `config/database.yml`.
+ ([Pull Request](https://github.com/rails/rails/pull/23461))
+
+* Added ability to call `ActionRecord::Relation#update` on relation objects
+ which will run validations on callbacks on all objects in the relation.
+ ([Pull Request](https://github.com/rails/rails/pull/11898))
+
+* Added `:touch` option to the `save` method so that records can be saved without
+ updating timestamps.
+ ([Pull Request](https://github.com/rails/rails/pull/18225))
+
+* Added expression indexes and operator classes support for PostgreSQL.
+ ([commit](https://github.com/rails/rails/commit/edc2b7718725016e988089b5fb6d6fb9d6e16882))
+
+* Added `:index_errors` option to add indexes to errors of nested attributes.
+ ([Pull Request](https://github.com/rails/rails/pull/19686))
+
+* Added support for bidirectional destroy dependencies.
+ ([Pull Request](https://github.com/rails/rails/pull/18548))
+
+* Added support for `after_commit` callbacks in transactional tests.
+ ([Pull Request](https://github.com/rails/rails/pull/18458))
+
+* Added `foreign_key_exists?` method to see if a foreign key exists on a table
+ or not.
+ ([Pull Request](https://github.com/rails/rails/pull/18662))
+
+* Added `:time` option to `touch` method to touch records with different time
+ than the current time.
+ ([Pull Request](https://github.com/rails/rails/pull/18956))
+
+* Change transaction callbacks to not swallow errors.
+ Before this change any errors raised inside a transaction callback
+ were getting rescued and printed in the logs, unless you used
+ the (newly deprecated) `raise_in_transactional_callbacks = true` option.
+
+ Now these errors are not rescued anymore and just bubble up, matching the
+ behavior of other callbacks.
+ ([commit](https://github.com/rails/rails/commit/07d3d402341e81ada0214f2cb2be1da69eadfe72))
+
+Active Model
+------------
+
+Please refer to the [Changelog][active-model] for detailed changes.
+
+### Removals
+
+* Removed deprecated `ActiveModel::Dirty#reset_#{attribute}` and
+ `ActiveModel::Dirty#reset_changes`.
+ ([Pull Request](https://github.com/rails/rails/commit/37175a24bd508e2983247ec5d011d57df836c743))
+
+* Removed XML serialization. This feature has been extracted into the
+ [activemodel-serializers-xml](https://github.com/rails/activemodel-serializers-xml) gem.
+ ([Pull Request](https://github.com/rails/rails/pull/21161))
+
+* Removed `ActionController::ModelNaming` module.
+ ([Pull Request](https://github.com/rails/rails/pull/18194))
+
+### Deprecations
+
+* Deprecated returning `false` as a way to halt Active Model and
+ `ActiveModel::Validations` callback chains. The recommended way is to
+ `throw(:abort)`. ([Pull Request](https://github.com/rails/rails/pull/17227))
+
+* Deprecated `ActiveModel::Errors#get`, `ActiveModel::Errors#set` and
+ `ActiveModel::Errors#[]=` methods that have inconsistent behavior.
+ ([Pull Request](https://github.com/rails/rails/pull/18634))
+
+* Deprecated the `:tokenizer` option for `validates_length_of`, in favor of
+ plain Ruby.
+ ([Pull Request](https://github.com/rails/rails/pull/19585))
+
+* Deprecated `ActiveModel::Errors#add_on_empty` and `ActiveModel::Errors#add_on_blank`
+ with no replacement.
+ ([Pull Request](https://github.com/rails/rails/pull/18996))
+
+### Notable changes
+
+* Added `ActiveModel::Errors#details` to determine what validator has failed.
+ ([Pull Request](https://github.com/rails/rails/pull/18322))
+
+* Extracted `ActiveRecord::AttributeAssignment` to `ActiveModel::AttributeAssignment`
+ allowing to use it for any object as an includable module.
+ ([Pull Request](https://github.com/rails/rails/pull/10776))
+
+* Added `ActiveModel::Dirty#[attr_name]_previously_changed?` and
+ `ActiveModel::Dirty#[attr_name]_previous_change` to improve access
+ to recorded changes after the model has been saved.
+ ([Pull Request](https://github.com/rails/rails/pull/19847))
+
+* Validate multiple contexts on `valid?` and `invalid?` at once.
+ ([Pull Request](https://github.com/rails/rails/pull/21069))
+
+* Change `validates_acceptance_of` to accept `true` as default value
+ apart from `1`.
+ ([Pull Request](https://github.com/rails/rails/pull/18439))
+
+Active Job
+-----------
+
+Please refer to the [Changelog][active-job] for detailed changes.
+
+### Notable changes
+
+* `ActiveJob::Base.deserialize` delegates to the job class. This allows jobs
+ to attach arbitrary metadata when they get serialized and read it back when
+ they get performed.
+ ([Pull Request](https://github.com/rails/rails/pull/18260))
+
+* Add ability to configure the queue adapter on a per job basis without
+ affecting each other.
+ ([Pull Request](https://github.com/rails/rails/pull/16992))
+
+* A generated job now inherits from `app/jobs/application_job.rb` by default.
+ ([Pull Request](https://github.com/rails/rails/pull/19034))
+
+* Allow `DelayedJob`, `Sidekiq`, `qu`, `que`, and `queue_classic` to report
+ the job id back to `ActiveJob::Base` as `provider_job_id`.
+ ([Pull Request](https://github.com/rails/rails/pull/20064),
+ [Pull Request](https://github.com/rails/rails/pull/20056),
+ [commit](https://github.com/rails/rails/commit/68e3279163d06e6b04e043f91c9470e9259bbbe0))
+
+* Implement a simple `AsyncJob` processor and associated `AsyncAdapter` that
+ queue jobs to a `concurrent-ruby` thread pool.
+ ([Pull Request](https://github.com/rails/rails/pull/21257))
+
+* Change the default adapter from inline to async. It's a better default as
+ tests will then not mistakenly come to rely on behavior happening
+ synchronously.
+ ([commit](https://github.com/rails/rails/commit/625baa69d14881ac49ba2e5c7d9cac4b222d7022))
+
+Active Support
+--------------
+
+Please refer to the [Changelog][active-support] for detailed changes.
+
+### Removals
+
+* Removed deprecated `ActiveSupport::JSON::Encoding::CircularReferenceError`.
+ ([commit](https://github.com/rails/rails/commit/d6e06ea8275cdc3f126f926ed9b5349fde374b10))
+
+* Removed deprecated methods `ActiveSupport::JSON::Encoding.encode_big_decimal_as_string=`
+ and `ActiveSupport::JSON::Encoding.encode_big_decimal_as_string`.
+ ([commit](https://github.com/rails/rails/commit/c8019c0611791b2716c6bed48ef8dcb177b7869c))
+
+* Removed deprecated `ActiveSupport::SafeBuffer#prepend`.
+ ([commit](https://github.com/rails/rails/commit/e1c8b9f688c56aaedac9466a4343df955b4a67ec))
+
+* Removed deprecated methods from `Kernel`. `silence_stderr`, `silence_stream`,
+ `capture` and `quietly`.
+ ([commit](https://github.com/rails/rails/commit/481e49c64f790e46f4aff3ed539ed227d2eb46cb))
+
+* Removed deprecated `active_support/core_ext/big_decimal/yaml_conversions`
+ file.
+ ([commit](https://github.com/rails/rails/commit/98ea19925d6db642731741c3b91bd085fac92241))
+
+* Removed deprecated methods `ActiveSupport::Cache::Store.instrument` and
+ `ActiveSupport::Cache::Store.instrument=`.
+ ([commit](https://github.com/rails/rails/commit/a3ce6ca30ed0e77496c63781af596b149687b6d7))
+
+* Removed deprecated `Class#superclass_delegating_accessor`.
+ Use `Class#class_attribute` instead.
+ ([Pull Request](https://github.com/rails/rails/pull/16938))
+
+* Removed deprecated `ThreadSafe::Cache`. Use `Concurrent::Map` instead.
+ ([Pull Request](https://github.com/rails/rails/pull/21679))
+
+* Removed `Object#itself` as it is implemented in Ruby 2.2.
+ ([Pull Request](https://github.com/rails/rails/pull/18244))
+
+### Deprecations
+
+* Deprecated `MissingSourceFile` in favor of `LoadError`.
+ ([commit](https://github.com/rails/rails/commit/734d97d2))
+
+* Deprecated `alias_method_chain` in favour of `Module#prepend` introduced in
+ Ruby 2.0.
+ ([Pull Request](https://github.com/rails/rails/pull/19434))
+
+* Deprecated `ActiveSupport::Concurrency::Latch` in favor of
+ `Concurrent::CountDownLatch` from concurrent-ruby.
+ ([Pull Request](https://github.com/rails/rails/pull/20866))
+
+* Deprecated `:prefix` option of `number_to_human_size` with no replacement.
+ ([Pull Request](https://github.com/rails/rails/pull/21191))
+
+* Deprecated `Module#qualified_const_` in favour of the builtin
+ `Module#const_` methods.
+ ([Pull Request](https://github.com/rails/rails/pull/17845))
+
+* Deprecated passing string to define callback.
+ ([Pull Request](https://github.com/rails/rails/pull/22598))
+
+* Deprecated `ActiveSupport::Cache::Store#namespaced_key`,
+ `ActiveSupport::Cache::MemCachedStore#escape_key`, and
+ `ActiveSupport::Cache::FileStore#key_file_path`.
+ Use `normalize_key` instead.
+ ([Pull Request](https://github.com/rails/rails/pull/22215),
+ [commit](https://github.com/rails/rails/commit/a8f773b0))
+
+* Deprecated `ActiveSupport::Cache::LocaleCache#set_cache_value` in favor of `write_cache_value`.
+ ([Pull Request](https://github.com/rails/rails/pull/22215))
+
+* Deprecated passing arguments to `assert_nothing_raised`.
+ ([Pull Request](https://github.com/rails/rails/pull/23789))
+
+* Deprecated `Module.local_constants` in favor of `Module.constants(false)`.
+ ([Pull Request](https://github.com/rails/rails/pull/23936))
+
+
+### Notable changes
+
+* Added `#verified` and `#valid_message?` methods to
+ `ActiveSupport::MessageVerifier`.
+ ([Pull Request](https://github.com/rails/rails/pull/17727))
+
+* Changed the way in which callback chains can be halted. The preferred method
+ to halt a callback chain from now on is to explicitly `throw(:abort)`.
+ ([Pull Request](https://github.com/rails/rails/pull/17227))
+
+* New config option
+ `config.active_support.halt_callback_chains_on_return_false` to specify
+ whether ActiveRecord, ActiveModel, and ActiveModel::Validations callback
+ chains can be halted by returning `false` in a 'before' callback.
+ ([Pull Request](https://github.com/rails/rails/pull/17227))
+
+* Changed the default test order from `:sorted` to `:random`.
+ ([commit](https://github.com/rails/rails/commit/5f777e4b5ee2e3e8e6fd0e2a208ec2a4d25a960d))
+
+* Added `#on_weekend?`, `#on_weekday?`, `#next_weekday`, `#prev_weekday` methods to `Date`,
+ `Time`, and `DateTime`.
+ ([Pull Request](https://github.com/rails/rails/pull/18335),
+ [Pull Request](https://github.com/rails/rails/pull/23687))
+
+* Added `same_time` option to `#next_week` and `#prev_week` for `Date`, `Time`,
+ and `DateTime`.
+ ([Pull Request](https://github.com/rails/rails/pull/18335))
+
+* Added `#prev_day` and `#next_day` counterparts to `#yesterday` and
+ `#tomorrow` for `Date`, `Time`, and `DateTime`.
+ ([Pull Request](https://github.com/rails/rails/pull/18335))
+
+* Added `SecureRandom.base58` for generation of random base58 strings.
+ ([commit](https://github.com/rails/rails/commit/b1093977110f18ae0cafe56c3d99fc22a7d54d1b))
+
+* Added `file_fixture` to `ActiveSupport::TestCase`.
+ It provides a simple mechanism to access sample files in your test cases.
+ ([Pull Request](https://github.com/rails/rails/pull/18658))
+
+* Added `#without` on `Enumerable` and `Array` to return a copy of an
+ enumerable without the specified elements.
+ ([Pull Request](https://github.com/rails/rails/pull/19157))
+
+* Added `ActiveSupport::ArrayInquirer` and `Array#inquiry`.
+ ([Pull Request](https://github.com/rails/rails/pull/18939))
+
+* Added `ActiveSupport::TimeZone#strptime` to allow parsing times as if
+ from a given timezone.
+ ([commit](https://github.com/rails/rails/commit/a5e507fa0b8180c3d97458a9b86c195e9857d8f6))
+
+* Added `Integer#positive?` and `Integer#negative?` query methods
+ in the vein of `Integer#zero?`.
+ ([commit](https://github.com/rails/rails/commit/e54277a45da3c86fecdfa930663d7692fd083daa))
+
+* Added a bang version to `ActiveSupport::OrderedOptions` get methods which will raise
+ an `KeyError` if the value is `.blank?`.
+ ([Pull Request](https://github.com/rails/rails/pull/20208))
+
+* Added `Time.days_in_year` to return the number of days in the given year, or the
+ current year if no argument is provided.
+ ([commit](https://github.com/rails/rails/commit/2f4f4d2cf1e4c5a442459fc250daf66186d110fa))
+
+* Added an evented file watcher to asynchronously detect changes in the
+ application source code, routes, locales, etc.
+ ([Pull Request](https://github.com/rails/rails/pull/22254))
+
+* Added thread_m/cattr_accessor/reader/writer suite of methods for declaring
+ class and module variables that live per-thread.
+ ([Pull Request](https://github.com/rails/rails/pull/22630))
+
+* Added `Array#second_to_last` and `Array#third_to_last` methods.
+ ([Pull Request](https://github.com/rails/rails/pull/23583))
+
+* Publish `ActiveSupport::Executor` and `ActiveSupport::Reloader` APIs to allow
+ components and libraries to manage, and participate in, the execution of
+ application code, and the application reloading process.
+ ([Pull Request](https://github.com/rails/rails/pull/23807))
+
+* `ActiveSupport::Duration` now supports ISO8601 formatting and parsing.
+ ([Pull Request](https://github.com/rails/rails/pull/16917))
+
+* `ActiveSupport::JSON.decode` now supports parsing ISO8601 local times when
+ `parse_json_times` is enabled.
+ ([Pull Request](https://github.com/rails/rails/pull/23011))
+
+* `ActiveSupport::JSON.decode` now return `Date` objects for date strings.
+ ([Pull Request](https://github.com/rails/rails/pull/23011))
+
+* Added ability to `TaggedLogging` to allow loggers to be instantiated multiple
+ times so that they don't share tags with each other.
+ ([Pull Request](https://github.com/rails/rails/pull/9065))
+
+Credits
+-------
+
+See the
+[full list of contributors to Rails](http://contributors.rubyonrails.org/) for
+the many people who spent many hours making Rails, the stable and robust
+framework it is. Kudos to all of them.
+
+[railties]: https://github.com/rails/rails/blob/5-0-stable/railties/CHANGELOG.md
+[action-pack]: https://github.com/rails/rails/blob/5-0-stable/actionpack/CHANGELOG.md
+[action-view]: https://github.com/rails/rails/blob/5-0-stable/actionview/CHANGELOG.md
+[action-mailer]: https://github.com/rails/rails/blob/5-0-stable/actionmailer/CHANGELOG.md
+[action-cable]: https://github.com/rails/rails/blob/5-0-stable/actioncable/CHANGELOG.md
+[active-record]: https://github.com/rails/rails/blob/5-0-stable/activerecord/CHANGELOG.md
+[active-model]: https://github.com/rails/rails/blob/5-0-stable/activemodel/CHANGELOG.md
+[active-support]: https://github.com/rails/rails/blob/5-0-stable/activesupport/CHANGELOG.md
+[active-job]: https://github.com/rails/rails/blob/5-0-stable/activejob/CHANGELOG.md