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diff --git a/guides/source/5_2_release_notes.md b/guides/source/5_2_release_notes.md new file mode 100644 index 0000000000..ab24c7e590 --- /dev/null +++ b/guides/source/5_2_release_notes.md @@ -0,0 +1,861 @@ +**DO NOT READ THIS FILE ON GITHUB, GUIDES ARE PUBLISHED ON http://guides.rubyonrails.org.** + +Ruby on Rails 5.2 Release Notes +=============================== + +Highlights in Rails 5.2: + +* Active Storage +* Redis Cache Store +* HTTP/2 Early Hints +* Credentials +* Content Security Policy + +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/5-2-stable) in the main Rails +repository on GitHub. + +-------------------------------------------------------------------------------- + +Upgrading to Rails 5.2 +---------------------- + +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 5.1 in case you +haven't and make sure your application still runs as expected before attempting +an update to Rails 5.2. 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-5-1-to-rails-5-2) +guide. + +Major Features +-------------- + +### Active Storage + +[Pull Request](https://github.com/rails/rails/pull/30020) + +[Active Storage](https://github.com/rails/rails/tree/5-2-stable/activestorage) +facilitates uploading files to a cloud storage service like +Amazon S3, Google Cloud Storage, or Microsoft Azure Storage and attaching +those files to Active Record objects. It comes with a local disk-based service +for development and testing and supports mirroring files to subordinate +services for backups and migrations. +You can read more about Active Storage in the +[Active Storage Overview](active_storage_overview.html) guide. + +### Redis Cache Store + +[Pull Request](https://github.com/rails/rails/pull/31134) + +Rails 5.2 ships with built-in Redis cache store. +You can read more about this in the +[Caching with Rails: An Overview](caching_with_rails.html#activesupport-cache-rediscachestore) +guide. + +### HTTP/2 Early Hints + +[Pull Request](https://github.com/rails/rails/pull/30744) + +Rails 5.2 supports [HTTP/2 Early Hints](https://tools.ietf.org/html/rfc8297). +To start the server with Early Hints enabled pass `--early-hints` +to `bin/rails server`. + +### Credentials + +[Pull Request](https://github.com/rails/rails/pull/30067) + +Added `config/credentials.yml.enc` file to store production app secrets. +It allows saving any authentication credentials for third-party services +directly in repository encrypted with a key in the `config/master.key` file or +the `RAILS_MASTER_KEY` environment variable. +This will eventually replace `Rails.application.secrets` and the encrypted +secrets introduced in Rails 5.1. +Furthermore, Rails 5.2 +[opens API underlying Credentials](https://github.com/rails/rails/pull/30940), +so you can easily deal with other encrypted configurations, keys, and files. +You can read more about this in the +[Securing Rails Applications](security.html#custom-credentials) +guide. + +### Content Security Policy + +[Pull Request](https://github.com/rails/rails/pull/31162) + +Rails 5.2 ships with a new DSL that allows you to configure a +[Content Security Policy](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy) +for your application. You can configure a global default policy and then +override it on a per-resource basis and even use lambdas to inject per-request +values into the header such as account subdomains in a multi-tenant application. +You can read more about this in the +[Securing Rails Applications](security.html#content-security-policy) +guide. + +Railties +-------- + +Please refer to the [Changelog][railties] for detailed changes. + +### Deprecations + +* Deprecate `capify!` method in generators and templates. + ([Pull Request](https://github.com/rails/rails/pull/29493)) + +* Passing the environment's name as a regular argument to the + `rails dbconsole` and `rails console` commands is deprecated. + The `-e` option should be used instead. + ([Commit](https://github.com/rails/rails/commit/48b249927375465a7102acc71c2dfb8d49af8309)) + +* Deprecate using subclass of `Rails::Application` to start the Rails server. + ([Pull Request](https://github.com/rails/rails/pull/30127)) + +* Deprecate `after_bundle` callback in Rails plugin templates. + ([Pull Request](https://github.com/rails/rails/pull/29446)) + +### Notable changes + +* Added a shared section to `config/database.yml` that will be loaded for + all environments. + ([Pull Request](https://github.com/rails/rails/pull/28896)) + +* Add `railtie.rb` to the plugin generator. + ([Pull Request](https://github.com/rails/rails/pull/29576)) + +* Clear screenshot files in `tmp:clear` task. + ([Pull Request](https://github.com/rails/rails/pull/29534)) + +* Skip unused components when running `bin/rails app:update`. + If the initial app generation skipped Action Cable, Active Record etc., + the update task honors those skips too. + ([Pull Request](https://github.com/rails/rails/pull/29645)) + +* Allow passing a custom connection name to the `rails dbconsole` + command when using a 3-level database configuration. + Example: `bin/rails dbconsole -c replica`. + ([Commit](https://github.com/rails/rails/commit/1acd9a6464668d4d54ab30d016829f60b70dbbeb)) + +* Properly expand shortcuts for environment's name running the `console` + and `dbconsole` commands. + ([Commit](https://github.com/rails/rails/commit/3777701f1380f3814bd5313b225586dec64d4104)) + +* Add `bootsnap` to default `Gemfile`. + ([Pull Request](https://github.com/rails/rails/pull/29313)) + +* Support `-` as a platform-agnostic way to run a script from stdin with + `rails runner` + ([Pull Request](https://github.com/rails/rails/pull/26343)) + +* Add `ruby x.x.x` version to `Gemfile` and create `.ruby-version` + root file containing the current Ruby version when new Rails applications + are created. + ([Pull Request](https://github.com/rails/rails/pull/30016)) + +* Add `--skip-action-cable` option to the plugin generator. + ([Pull Request](https://github.com/rails/rails/pull/30164)) + +* Add `git_source` to `Gemfile` for plugin generator. + ([Pull Request](https://github.com/rails/rails/pull/30110)) + +* Skip unused components when running `bin/rails` in Rails plugin. + ([Commit](https://github.com/rails/rails/commit/62499cb6e088c3bc32a9396322c7473a17a28640)) + +* Optimize indentation for generator actions. + ([Pull Request](https://github.com/rails/rails/pull/30166)) + +* Optimize routes indentation. + ([Pull Request](https://github.com/rails/rails/pull/30241)) + +* Add `--skip-yarn` option to the plugin generator. + ([Pull Request](https://github.com/rails/rails/pull/30238)) + +* Support multiple versions arguments for `gem` method of Generators. + ([Pull Request](https://github.com/rails/rails/pull/30323)) + +* Derive `secret_key_base` from the app name in development and test + environments. + ([Pull Request](https://github.com/rails/rails/pull/30067)) + +* Add `mini_magick` to default `Gemfile` as comment. + ([Pull Request](https://github.com/rails/rails/pull/30633)) + +* `rails new` and `rails plugin new` get `Active Storage` by default. + Add ability to skip `Active Storage` with `--skip-active-storage` + and do so automatically when `--skip-active-record` is used. + ([Pull Request](https://github.com/rails/rails/pull/30101)) + +Action Cable +------------ + +Please refer to the [Changelog][action-cable] for detailed changes. + +### Removals + +* Removed deprecated evented redis adapter. + ([Commit](https://github.com/rails/rails/commit/48766e32d31651606b9f68a16015ad05c3b0de2c)) + +### Notable changes + +* Add support for `host`, `port`, `db` and `password` options in cable.yml + ([Pull Request](https://github.com/rails/rails/pull/29528)) + +* Hash long stream identifiers when using PostgreSQL adapter. + ([Pull Request](https://github.com/rails/rails/pull/29297)) + +Action Pack +----------- + +Please refer to the [Changelog][action-pack] for detailed changes. + +### Removals + +* Remove deprecated `ActionController::ParamsParser::ParseError`. + ([Commit](https://github.com/rails/rails/commit/e16c765ac6dcff068ff2e5554d69ff345c003de1)) + +### Deprecations + +* Deprecate `#success?`, `#missing?` and `#error?` aliases of + `ActionDispatch::TestResponse`. + ([Pull Request](https://github.com/rails/rails/pull/30104)) + +### Notable changes + +* Add support for recyclable cache keys with fragment caching. + ([Pull Request](https://github.com/rails/rails/pull/29092)) + +* Change the cache key format for fragments to make it easier to debug key + churn. + ([Pull Request](https://github.com/rails/rails/pull/29092)) + +* AEAD encrypted cookies and sessions with GCM. + ([Pull Request](https://github.com/rails/rails/pull/28132)) + +* Protect from forgery by default. + ([Pull Request](https://github.com/rails/rails/pull/29742)) + +* Enforce signed/encrypted cookie expiry server side. + ([Pull Request](https://github.com/rails/rails/pull/30121)) + +* Cookies `:expires` option supports `ActiveSupport::Duration` object. + ([Pull Request](https://github.com/rails/rails/pull/30121)) + +* Use Capybara registered `:puma` server config. + ([Pull Request](https://github.com/rails/rails/pull/30638)) + +* Simplify cookies middleware with key rotation support. + ([Pull Request](https://github.com/rails/rails/pull/29716)) + +* Add ability to enable Early Hints for HTTP/2. + ([Pull Request](https://github.com/rails/rails/pull/30744)) + +* Add headless chrome support to System Tests. + ([Pull Request](https://github.com/rails/rails/pull/30876)) + +* Add `:allow_other_host` option to `redirect_back` method. + ([Pull Request](https://github.com/rails/rails/pull/30850)) + +* Make `assert_recognizes` to traverse mounted engines. + ([Pull Request](https://github.com/rails/rails/pull/22435)) + +* Add DSL for configuring Content-Security-Policy header. + ([Pull Request](https://github.com/rails/rails/pull/31162), + [Commit](https://github.com/rails/rails/commit/619b1b6353a65e1635d10b8f8c6630723a5a6f1a), + [Commit](https://github.com/rails/rails/commit/4ec8bf68ff92f35e79232fbd605012ce1f4e1e6e)) + +* Register most popular audio/video/font mime types supported by modern + browsers. + ([Pull Request](https://github.com/rails/rails/pull/31251)) + +* Changed the default system test screenshot output from `inline` to `simple`. + ([Commit](https://github.com/rails/rails/commit/9d6e288ee96d6241f864dbf90211c37b14a57632)) + +* Add headless firefox support to System Tests. + ([Pull Request](https://github.com/rails/rails/pull/31365)) + +* Add secure `X-Download-Options` and `X-Permitted-Cross-Domain-Policies` to + default headers set. + ([Commit](https://github.com/rails/rails/commit/5d7b70f4336d42eabfc403e9f6efceb88b3eff44)) + +* Changed the system tests to set Puma as default server only when the + user haven't specified manually another server. + ([Pull Request](https://github.com/rails/rails/pull/31384)) + +* Add `Referrer-Policy` header to default headers set. + ([Commit](https://github.com/rails/rails/commit/428939be9f954d39b0c41bc53d85d0d106b9d1a1)) + +* Matches behavior of `Hash#each` in `ActionController::Parameters#each`. + ([Pull Request](https://github.com/rails/rails/pull/27790)) + +* Add support for automatic nonce generation for Rails UJS. + ([Commit](https://github.com/rails/rails/commit/b2f0a8945956cd92dec71ec4e44715d764990a49)) + +* Update the default HSTS max-age value to 31536000 seconds (1 year) + to meet the minimum max-age requirement for https://hstspreload.org/. + ([Commit](https://github.com/rails/rails/commit/30b5f469a1d30c60d1fb0605e84c50568ff7ed37)) + +* Add alias method `to_hash` to `to_h` for `cookies`. + Add alias method `to_h` to `to_hash` for `session`. + ([Commit](https://github.com/rails/rails/commit/50a62499e41dfffc2903d468e8b47acebaf9b500)) + +Action View +----------- + +Please refer to the [Changelog][action-view] for detailed changes. + +### Removals + +* Remove deprecated Erubis ERB handler. + ([Commit](https://github.com/rails/rails/commit/7de7f12fd140a60134defe7dc55b5a20b2372d06)) + +### Deprecations + +* Deprecate `image_alt` helper which used to add default alt text to + the images generated by `image_tag`. + ([Pull Request](https://github.com/rails/rails/pull/30213)) + +### Notable changes + +* Add `:json` type to `auto_discovery_link_tag` to support + [JSON Feeds](https://jsonfeed.org/version/1). + ([Pull Request](https://github.com/rails/rails/pull/29158)) + +* Add `srcset` option to `image_tag` helper. + ([Pull Request](https://github.com/rails/rails/pull/29349)) + +* Fix issues with `field_error_proc` wrapping `optgroup` and + select divider `option`. + ([Pull Request](https://github.com/rails/rails/pull/31088)) + +* Change `form_with` to generates ids by default. + ([Commit](https://github.com/rails/rails/commit/260d6f112a0ffdbe03e6f5051504cb441c1e94cd)) + +* Add `preload_link_tag` helper. + ([Pull Request](https://github.com/rails/rails/pull/31251)) + +* Allow the use of callable objects as group methods for grouped selects. + ([Pull Request](https://github.com/rails/rails/pull/31578)) + +Action Mailer +------------- + +Please refer to the [Changelog][action-mailer] for detailed changes. + +### Notable changes + +* Allow Action Mailer classes to configure their delivery job. + ([Pull Request](https://github.com/rails/rails/pull/29457)) + +* Add `assert_enqueued_email_with` test helper. + ([Pull Request](https://github.com/rails/rails/pull/30695)) + +Active Record +------------- + +Please refer to the [Changelog][active-record] for detailed changes. + +### Removals + +* Remove deprecated `#migration_keys`. + ([Pull Request](https://github.com/rails/rails/pull/30337)) + +* Remove deprecated support to `quoted_id` when typecasting + an Active Record object. + ([Commit](https://github.com/rails/rails/commit/82472b3922bda2f337a79cef961b4760d04f9689)) + +* Remove deprecated argument `default` from `index_name_exists?`. + ([Commit](https://github.com/rails/rails/commit/8f5b34df81175e30f68879479243fbce966122d7)) + +* Remove deprecated support to passing a class to `:class_name` + on associations. + ([Commit](https://github.com/rails/rails/commit/e65aff70696be52b46ebe57207ebd8bb2cfcdbb6)) + +* Remove deprecated methods `initialize_schema_migrations_table` and + `initialize_internal_metadata_table`. + ([Commit](https://github.com/rails/rails/commit/c9660b5777707658c414b430753029cd9bc39934)) + +* Remove deprecated method `supports_migrations?`. + ([Commit](https://github.com/rails/rails/commit/9438c144b1893f2a59ec0924afe4d46bd8d5ffdd)) + +* Remove deprecated method `supports_primary_key?`. + ([Commit](https://github.com/rails/rails/commit/c56ff22fc6e97df4656ddc22909d9bf8b0c2cbb1)) + +* Remove deprecated method + `ActiveRecord::Migrator.schema_migrations_table_name`. + ([Commit](https://github.com/rails/rails/commit/7df6e3f3cbdea9a0460ddbab445c81fbb1cfd012)) + +* Remove deprecated argument `name` from `#indexes`. + ([Commit](https://github.com/rails/rails/commit/d6b779ecebe57f6629352c34bfd6c442ac8fba0e)) + +* Remove deprecated arguments from `#verify!`. + ([Commit](https://github.com/rails/rails/commit/9c6ee1bed0292fc32c23dc1c68951ae64fc510be)) + +* Remove deprecated configuration `.error_on_ignored_order_or_limit`. + ([Commit](https://github.com/rails/rails/commit/e1066f450d1a99c9a0b4d786b202e2ca82a4c3b3)) + +* Remove deprecated method `#scope_chain`. + ([Commit](https://github.com/rails/rails/commit/ef7784752c5c5efbe23f62d2bbcc62d4fd8aacab)) + +* Remove deprecated method `#sanitize_conditions`. + ([Commit](https://github.com/rails/rails/commit/8f5413b896099f80ef46a97819fe47a820417bc2)) + +### Deprecations + +* Deprecate `supports_statement_cache?`. + ([Pull Request](https://github.com/rails/rails/pull/28938)) + +* Deprecate passing arguments and block at the same time to + `count` and `sum` in `ActiveRecord::Calculations`. + ([Pull Request](https://github.com/rails/rails/pull/29262)) + +* Deprecate delegating to `arel` in `Relation`. + ([Pull Request](https://github.com/rails/rails/pull/29619)) + +* Deprecate `set_state` method in `TransactionState`. + ([Commit](https://github.com/rails/rails/commit/608ebccf8f6314c945444b400a37c2d07f21b253)) + +* Deprecate `expand_hash_conditions_for_aggregates` without replacement. + ([Commit](https://github.com/rails/rails/commit/7ae26885d96daee3809d0bd50b1a440c2f5ffb69)) + +### Notable changes + +* When calling the dynamic fixture accessor method with no arguments, it now + returns all fixtures of this type. Previously this method always returned + an empty array. + ([Pull Request](https://github.com/rails/rails/pull/28692)) + +* Fix inconsistency with changed attributes when overriding + Active Record attribute reader. + ([Pull Request](https://github.com/rails/rails/pull/28661)) + +* Support Descending Indexes for MySQL. + ([Pull Request](https://github.com/rails/rails/pull/28773)) + +* Fix `bin/rails db:forward` first migration. + ([Commit](https://github.com/rails/rails/commit/b77d2aa0c336492ba33cbfade4964ba0eda3ef84)) + +* Raise error `UnknownMigrationVersionError` on the movement of migrations + when the current migration does not exist. + ([Commit](https://github.com/rails/rails/commit/bb9d6eb094f29bb94ef1f26aa44f145f17b973fe)) + +* Respect `SchemaDumper.ignore_tables` in rake tasks for + databases structure dump. + ([Pull Request](https://github.com/rails/rails/pull/29077)) + +* Add `ActiveRecord::Base#cache_version` to support recyclable cache keys via + the new versioned entries in `ActiveSupport::Cache`. This also means that + `ActiveRecord::Base#cache_key` will now return a stable key that + does not include a timestamp any more. + ([Pull Request](https://github.com/rails/rails/pull/29092)) + +* Prevent creation of bind param if casted value is nil. + ([Pull Request](https://github.com/rails/rails/pull/29282)) + +* Use bulk INSERT to insert fixtures for better performance. + ([Pull Request](https://github.com/rails/rails/pull/29504)) + +* Merging two relations representing nested joins no longer transforms + the joins of the merged relation into LEFT OUTER JOIN. + ([Pull Request](https://github.com/rails/rails/pull/27063)) + +* Fix transactions to apply state to child transactions. + Previously, if you had a nested transaction and the outer transaction was + rolledback, the record from the inner transaction would still be marked + as persisted. It was fixed by applying the state of the parent + transaction to the child transaction when the parent transaction is + rolledback. This will correctly mark records from the inner transaction + as not persisted. + ([Commit](https://github.com/rails/rails/commit/0237da287eb4c507d10a0c6d94150093acc52b03)) + +* Fix eager loading/preloading association with scope including joins. + ([Pull Request](https://github.com/rails/rails/pull/29413)) + +* Prevent errors raised by `sql.active_record` notification subscribers + from being converted into `ActiveRecord::StatementInvalid` exceptions. + ([Pull Request](https://github.com/rails/rails/pull/29692)) + +* Skip query caching when working with batches of records + (`find_each`, `find_in_batches`, `in_batches`). + ([Commit](https://github.com/rails/rails/commit/b83852e6eed5789b23b13bac40228e87e8822b4d)) + +* Change sqlite3 boolean serialization to use 1 and 0. + SQLite natively recognizes 1 and 0 as true and false, but does not natively + recognize 't' and 'f' as was previously serialized. + ([Pull Request](https://github.com/rails/rails/pull/29699)) + +* Values constructed using multi-parameter assignment will now use the + post-type-cast value for rendering in single-field form inputs. + ([Commit](https://github.com/rails/rails/commit/1519e976b224871c7f7dd476351930d5d0d7faf6)) + +* `ApplicationRecord` is no longer generated when generating models. If you + need to generate it, it can be created with `rails g application_record`. + ([Pull Request](https://github.com/rails/rails/pull/29916)) + +* `Relation#or` now accepts two relations who have different values for + `references` only, as `references` can be implicitly called by `where`. + ([Commit](https://github.com/rails/rails/commit/ea6139101ccaf8be03b536b1293a9f36bc12f2f7)) + +* When using `Relation#or`, extract the common conditions and + put them before the OR condition. + ([Pull Request](https://github.com/rails/rails/pull/29950)) + +* Add `binary` fixture helper method. + ([Pull Request](https://github.com/rails/rails/pull/30073)) + +* Automatically guess the inverse associations for STI. + ([Pull Request](https://github.com/rails/rails/pull/23425)) + +* Add new error class `LockWaitTimeout` which will be raised + when lock wait timeout exceeded. + ([Pull Request](https://github.com/rails/rails/pull/30360)) + +* Update payload names for `sql.active_record` instrumentation to be + more descriptive. + ([Pull Request](https://github.com/rails/rails/pull/30619)) + +* Use given algorithm while removing index from database. + ([Pull Request](https://github.com/rails/rails/pull/24199)) + +* Passing a `Set` to `Relation#where` now behaves the same as passing + an array. + ([Commit](https://github.com/rails/rails/commit/9cf7e3494f5bd34f1382c1ff4ea3d811a4972ae2)) + +* PostgreSQL `tsrange` now preserves subsecond precision. + ([Pull Request](https://github.com/rails/rails/pull/30725)) + +* Raises when calling `lock!` in a dirty record. + ([Commit](https://github.com/rails/rails/commit/63cf15877bae859ff7b4ebaf05186f3ca79c1863)) + +* Fixed a bug where column orders for an index weren't written to + `db/schema.rb` when using the sqlite adapter. + ([Pull Request](https://github.com/rails/rails/pull/30970)) + +* Fix `bin/rails db:migrate` with specified `VERSION`. + `bin/rails db:migrate` with empty VERSION behaves as without `VERSION`. + Check a format of `VERSION`: Allow a migration version number + or name of a migration file. Raise error if format of `VERSION` is invalid. + Raise error if target migration doesn't exist. + ([Pull Request](https://github.com/rails/rails/pull/30714)) + +* Add new error class `StatementTimeout` which will be raised + when statement timeout exceeded. + ([Pull Request](https://github.com/rails/rails/pull/31129)) + +* `update_all` will now pass its values to `Type#cast` before passing them to + `Type#serialize`. This means that `update_all(foo: 'true')` will properly + persist a boolean. + ([Commit](https://github.com/rails/rails/commit/68fe6b08ee72cc47263e0d2c9ff07f75c4b42761)) + +* Require raw SQL fragments to be explicitly marked when used in + relation query methods. + ([Commit](https://github.com/rails/rails/commit/a1ee43d2170dd6adf5a9f390df2b1dde45018a48), + [Commit](https://github.com/rails/rails/commit/e4a921a75f8702a7dbaf41e31130fe884dea93f9)) + +* Add `#up_only` to database migrations for code that is only relevant when + migrating up, e.g. populating a new column. + ([Pull Request](https://github.com/rails/rails/pull/31082)) + +* Add new error class `QueryCanceled` which will be raised + when canceling statement due to user request. + ([Pull Request](https://github.com/rails/rails/pull/31235)) + +* Don't allow scopes to be defined which conflict with instance methods + on `Relation`. + ([Pull Request](https://github.com/rails/rails/pull/31179)) + +* Add support for PostgreSQL operator classes to `add_index`. + ([Pull Request](https://github.com/rails/rails/pull/19090)) + +* Log database query callers. + ([Pull Request](https://github.com/rails/rails/pull/26815), + [Pull Request](https://github.com/rails/rails/pull/31519), + [Pull Request](https://github.com/rails/rails/pull/31690)) + +* Undefine attribute methods on descendants when resetting column information. + ([Pull Request](https://github.com/rails/rails/pull/31475)) + +* Using subselect for `delete_all` with `limit` or `offset`. + ([Commit](https://github.com/rails/rails/commit/9e7260da1bdc0770cf4ac547120c85ab93ff3d48)) + +* Fixed inconsistency with `first(n)` when used with `limit()`. + The `first(n)` finder now respects the `limit()`, making it consistent + with `relation.to_a.first(n)`, and also with the behavior of `last(n)`. + ([Pull Request](https://github.com/rails/rails/pull/27597)) + +* Fix nested `has_many :through` associations on unpersisted parent instances. + ([Commit](https://github.com/rails/rails/commit/027f865fc8b262d9ba3ee51da3483e94a5489b66)) + +* Take into account association conditions when deleting through records. + ([Commit](https://github.com/rails/rails/commit/ae48c65e411e01c1045056562319666384bb1b63)) + +* Don't allow destroyed object mutation after `save` or `save!` is called. + ([Commit](https://github.com/rails/rails/commit/562dd0494a90d9d47849f052e8913f0050f3e494)) + +* Fix relation merger issue with `left_outer_joins`. + ([Pull Request](https://github.com/rails/rails/pull/27860)) + +* Support for PostgreSQL foreign tables. + ([Pull Request](https://github.com/rails/rails/pull/31549)) + +* Clear the transaction state when an Active Record object is duped. + ([Pull Request](https://github.com/rails/rails/pull/31751)) + +* Fix not expanded problem when passing an Array object as argument + to the where method using `composed_of` column. + ([Pull Request](https://github.com/rails/rails/pull/31724)) + +* Make `reflection.klass` raise if `polymorphic?` not to be misused. + ([Commit](https://github.com/rails/rails/commit/63fc1100ce054e3e11c04a547cdb9387cd79571a)) + +* Fix `#columns_for_distinct` of MySQL and PostgreSQL to make + `ActiveRecord::FinderMethods#limited_ids_for` use correct primary key values + even if `ORDER BY` columns include other table's primary key. + ([Commit](https://github.com/rails/rails/commit/851618c15750979a75635530200665b543561a44)) + +* Fix `dependent: :destroy` issue for has_one/belongs_to relationship where + the parent class was getting deleted when the child was not. + ([Commit](https://github.com/rails/rails/commit/b0fc04aa3af338d5a90608bf37248668d59fc881)) + +Active Model +------------ + +Please refer to the [Changelog][active-model] for detailed changes. + +### Notable changes + +* Fix methods `#keys`, `#values` in `ActiveModel::Errors`. + Change `#keys` to only return the keys that don't have empty messages. + Change `#values` to only return the not empty values. + ([Pull Request](https://github.com/rails/rails/pull/28584)) + +* Add method `#merge!` for `ActiveModel::Errors`. + ([Pull Request](https://github.com/rails/rails/pull/29714)) + +* Allow passing a Proc or Symbol to length validator options. + ([Pull Request](https://github.com/rails/rails/pull/30674)) + +* Execute `ConfirmationValidator` validation when `_confirmation`'s value + is `false`. + ([Pull Request](https://github.com/rails/rails/pull/31058)) + +* Models using the attributes API with a proc default can now be marshalled. + ([Commit](https://github.com/rails/rails/commit/0af36c62a5710e023402e37b019ad9982e69de4b)) + +* Do not lose all multiple `:includes` with options in serialization. + ([Commit](https://github.com/rails/rails/commit/853054bcc7a043eea78c97e7705a46abb603cc44)) + +Active Support +-------------- + +Please refer to the [Changelog][active-support] for detailed changes. + +### Removals + +* Remove deprecated `:if` and `:unless` string filter for callbacks. + ([Commit](https://github.com/rails/rails/commit/c792354adcbf8c966f274915c605c6713b840548)) + +* Remove deprecated `halt_callback_chains_on_return_false` option. + ([Commit](https://github.com/rails/rails/commit/19fbbebb1665e482d76cae30166b46e74ceafe29)) + +### Deprecations + +* Deprecate `Module#reachable?` method. + ([Pull Request](https://github.com/rails/rails/pull/30624)) + +* Deprecate `secrets.secret_token`. + ([Commit](https://github.com/rails/rails/commit/fbcc4bfe9a211e219da5d0bb01d894fcdaef0a0e)) + +### Notable changes + +* Add `fetch_values` for `HashWithIndifferentAccess`. + ([Pull Request](https://github.com/rails/rails/pull/28316)) + +* Add support for `:offset` to `Time#change`. + ([Commit](https://github.com/rails/rails/commit/851b7f866e13518d900407c78dcd6eb477afad06)) + +* Add support for `:offset` and `:zone` + to `ActiveSupport::TimeWithZone#change`. + ([Commit](https://github.com/rails/rails/commit/851b7f866e13518d900407c78dcd6eb477afad06)) + +* Pass gem name and deprecation horizon to deprecation notifications. + ([Pull Request](https://github.com/rails/rails/pull/28800)) + +* Add support for versioned cache entries. This enables the cache stores to + recycle cache keys, greatly saving on storage in cases with frequent churn. + Works together with the separation of `#cache_key` and `#cache_version` + in Active Record and its use in Action Pack's fragment caching. + ([Pull Request](https://github.com/rails/rails/pull/29092)) + +* Add `ActiveSupport::CurrentAttributes` to provide a thread-isolated + attributes singleton. Primary use case is keeping all the per-request + attributes easily available to the whole system. + ([Pull Request](https://github.com/rails/rails/pull/29180)) + +* `#singularize` and `#pluralize` now respect uncountables for + the specified locale. + ([Commit](https://github.com/rails/rails/commit/352865d0f835c24daa9a2e9863dcc9dde9e5371a)) + +* Add default option to `class_attribute`. + ([Pull Request](https://github.com/rails/rails/pull/29270)) + +* Add `Date#prev_occurring` and `Date#next_occurring` to return + specified next/previous occurring day of week. + ([Pull Request](https://github.com/rails/rails/pull/26600)) + +* Add default option to module and class attribute accessors. + ([Pull Request](https://github.com/rails/rails/pull/29294)) + +* Cache: `write_multi`. + ([Pull Request](https://github.com/rails/rails/pull/29366)) + +* Default `ActiveSupport::MessageEncryptor` to use AES 256 GCM encryption. + ([Pull Request](https://github.com/rails/rails/pull/29263)) + +* Add `freeze_time` helper which freezes time to `Time.now` in tests. + ([Pull Request](https://github.com/rails/rails/pull/29681)) + +* Make the order of `Hash#reverse_merge!` consistent + with `HashWithIndifferentAccess`. + ([Pull Request](https://github.com/rails/rails/pull/28077)) + +* Add purpose and expiry support to `ActiveSupport::MessageVerifier` and + `ActiveSupport::MessageEncryptor`. + ([Pull Request](https://github.com/rails/rails/pull/29892)) + +* Update `String#camelize` to provide feedback when wrong option is passed. + ([Pull Request](https://github.com/rails/rails/pull/30039)) + +* `Module#delegate_missing_to` now raises `DelegationError` if target is nil, + similar to `Module#delegate`. + ([Pull Request](https://github.com/rails/rails/pull/30191)) + +* Add `ActiveSupport::EncryptedFile` and + `ActiveSupport::EncryptedConfiguration`. + ([Pull Request](https://github.com/rails/rails/pull/30067)) + +* Add `config/credentials.yml.enc` to store production app secrets. + ([Pull Request](https://github.com/rails/rails/pull/30067)) + +* Add key rotation support to `MessageEncryptor` and `MessageVerifier`. + ([Pull Request](https://github.com/rails/rails/pull/29716)) + +* Return an instance of `HashWithIndifferentAccess` from + `HashWithIndifferentAccess#transform_keys`. + ([Pull Request](https://github.com/rails/rails/pull/30728)) + +* `Hash#slice` now falls back to Ruby 2.5+'s built-in definition if defined. + ([Commit](https://github.com/rails/rails/commit/01ae39660243bc5f0a986e20f9c9bff312b1b5f8)) + +* `IO#to_json` now returns the `to_s` representation, rather than + attempting to convert to an array. This fixes a bug where `IO#to_json` + would raise an `IOError` when called on an unreadable object. + ([Pull Request](https://github.com/rails/rails/pull/30953)) + +* Add same method signature for `Time#prev_day` and `Time#next_day` + in accordance with `Date#prev_day`, `Date#next_day`. + Allows pass argument for `Time#prev_day` and `Time#next_day`. + ([Commit](https://github.com/rails/rails/commit/61ac2167eff741bffb44aec231f4ea13d004134e)) + +* Add same method signature for `Time#prev_month` and `Time#next_month` + in accordance with `Date#prev_month`, `Date#next_month`. + Allows pass argument for `Time#prev_month` and `Time#next_month`. + ([Commit](https://github.com/rails/rails/commit/f2c1e3a793570584d9708aaee387214bc3543530)) + +* Add same method signature for `Time#prev_year` and `Time#next_year` + in accordance with `Date#prev_year`, `Date#next_year`. + Allows pass argument for `Time#prev_year` and `Time#next_year`. + ([Commit](https://github.com/rails/rails/commit/ee9d81837b5eba9d5ec869ae7601d7ffce763e3e)) + +* Fix acronym support in `humanize`. + ([Commit](https://github.com/rails/rails/commit/0ddde0a8fca6a0ca3158e3329713959acd65605d)) + +* Allow `Range#include?` on TWZ ranges. + ([Pull Request](https://github.com/rails/rails/pull/31081)) + +* Cache: Enable compression by default for values > 1kB. + ([Pull Request](https://github.com/rails/rails/pull/31147)) + +* Redis cache store. + ([Pull Request](https://github.com/rails/rails/pull/31134), + [Pull Request](https://github.com/rails/rails/pull/31866)) + +* Handle `TZInfo::AmbiguousTime` errors. + ([Pull Request](https://github.com/rails/rails/pull/31128)) + +* MemCacheStore: Support expiring counters. + ([Commit](https://github.com/rails/rails/commit/b22ee64b5b30c6d5039c292235e10b24b1057f6d)) + +* Make `ActiveSupport::TimeZone.all` return only time zones that are in + `ActiveSupport::TimeZone::MAPPING`. + ([Pull Request](https://github.com/rails/rails/pull/31176)) + +* Changed default behaviour of `ActiveSupport::SecurityUtils.secure_compare`, + to make it not leak length information even for variable length string. + Renamed old `ActiveSupport::SecurityUtils.secure_compare` to + `fixed_length_secure_compare`, and started raising `ArgumentError` in + case of length mismatch of passed strings. + ([Pull Request](https://github.com/rails/rails/pull/24510)) + +* Use SHA-1 to generate non-sensitive digests, such as the ETag header. + ([Pull Request](https://github.com/rails/rails/pull/31289), + [Pull Request](https://github.com/rails/rails/pull/31651)) + +* `assert_changes` will always assert that the expression changes, + regardless of `from:` and `to:` argument combinations. + ([Pull Request](https://github.com/rails/rails/pull/31011)) + +* Add missing instrumentation for `read_multi` + in `ActiveSupport::Cache::Store`. + ([Pull Request](https://github.com/rails/rails/pull/30268)) + +* Support hash as first argument in `assert_difference`. + This allows to specify multiple numeric differences in the same assertion. + ([Pull Request](https://github.com/rails/rails/pull/31600)) + +* Caching: MemCache and Redis `read_multi` and `fetch_multi` speedup. + Read from the local in-memory cache before consulting the backend. + ([Commit](https://github.com/rails/rails/commit/a2b97e4ffef971607a1be8fc7909f099b6840f36)) + +Active Job +---------- + +Please refer to the [Changelog][active-job] for detailed changes. + +### Notable changes + +* Allow block to be passed to `ActiveJob::Base.discard_on` to allow custom + handling of discard jobs. + ([Pull Request](https://github.com/rails/rails/pull/30622)) + +Ruby on Rails Guides +-------------------- + +Please refer to the [Changelog][guides] for detailed changes. + +### Notable changes + +* Add + [Threading and Code Execution in Rails](threading_and_code_execution.html) + Guide. + ([Pull Request](https://github.com/rails/rails/pull/27494)) + +* Add [Active Storage Overview](active_storage_overview.html) Guide. + ([Pull Request](https://github.com/rails/rails/pull/31037)) + +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/5-2-stable/railties/CHANGELOG.md +[action-pack]: https://github.com/rails/rails/blob/5-2-stable/actionpack/CHANGELOG.md +[action-view]: https://github.com/rails/rails/blob/5-2-stable/actionview/CHANGELOG.md +[action-mailer]: https://github.com/rails/rails/blob/5-2-stable/actionmailer/CHANGELOG.md +[action-cable]: https://github.com/rails/rails/blob/5-2-stable/actioncable/CHANGELOG.md +[active-record]: https://github.com/rails/rails/blob/5-2-stable/activerecord/CHANGELOG.md +[active-model]: https://github.com/rails/rails/blob/5-2-stable/activemodel/CHANGELOG.md +[active-support]: https://github.com/rails/rails/blob/5-2-stable/activesupport/CHANGELOG.md +[active-job]: https://github.com/rails/rails/blob/5-2-stable/activejob/CHANGELOG.md +[guides]: https://github.com/rails/rails/blob/5-2-stable/guides/CHANGELOG.md |