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-rw-r--r--guides/source/4_2_release_notes.md118
1 files changed, 102 insertions, 16 deletions
diff --git a/guides/source/4_2_release_notes.md b/guides/source/4_2_release_notes.md
index be007f93a7..f4c2eb8945 100644
--- a/guides/source/4_2_release_notes.md
+++ b/guides/source/4_2_release_notes.md
@@ -25,14 +25,37 @@ guide.
Major Features
--------------
+### Foreign key support
+
+The migration DSL now supports adding and removing foreign keys. They are dumped
+to `schema.rb` as well. At this time, only the `mysql`, `mysql2` and `postgresql`
+adapters support foreign keys.
+
+```ruby
+# add a foreign key to `articles.author_id` referencing `authors.id`
+add_foreign_key :articles, :authors
+
+# add a foreign key to `articles.author_id` referencing `users.lng_id`
+add_foreign_key :articles, :users, column: :author_id, primary_key: "lng_id"
+
+# remove the foreign key on `accounts.branch_id`
+remove_foreign_key :accounts, :branches
+
+# remove the foreign key on `accounts.owner_id`
+remove_foreign_key :accounts, column: :owner_id
+```
+
+See the API documentation on
+[add_foreign_key](http://api.rubyonrails.org/v4.2.0/classes/ActiveRecord/ConnectionAdapters/SchemaStatements.html#method-i-add_foreign_key)
+and
+[remove_foreign_key](http://api.rubyonrails.org/v4.2.0/classes/ActiveRecord/ConnectionAdapters/SchemaStatements.html#method-i-remove_foreign_key)
+for a full description.
Railties
--------
-Please refer to the
-[Changelog](https://github.com/rails/rails/blob/4-2-stable/railties/CHANGELOG.md)
-for detailed changes.
+Please refer to the [Changelog][railties] for detailed changes.
### Removals
@@ -57,13 +80,11 @@ for detailed changes.
Action Pack
-----------
-Please refer to the
-[Changelog](https://github.com/rails/rails/blob/4-2-stable/actionpack/CHANGELOG.md)
-for detailed changes.
+Please refer to the [Changelog][action-pack] for detailed changes.
### Deprecations
-* Deprecated support for setting the `to:` option of a router to a symbol or a
+* Deprecated support for setting the `:to` option of a router to a symbol or a
string that does not contain a `#` character:
get '/posts', to: MyRackApp => (No change necessary)
@@ -115,12 +136,29 @@ for detailed changes.
([Pull Request](https://github.com/rails/rails/pull/14280))
+Action View
+-------------
+
+Please refer to the [Changelog][action-view] for detailed changes.
+
+### Deprecations
+
+* Deprecated `AbstractController::Base.parent_prefixes`.
+ Override `AbstractController::Base.local_prefixes` when you want to change
+ where to find views.
+ ([Pull Request](https://github.com/rails/rails/pull/15026))
+
+* Deprecated `ActionView::Digestor#digest(name, format, finder, options = {})`,
+ arguments should be passed as a hash instead.
+ ([Pull Request](https://github.com/rails/rails/pull/14243))
+
+### Notable changes
+
+
Action Mailer
-------------
-Please refer to the
-[Changelog](https://github.com/rails/rails/blob/4-2-stable/actionmailer/CHANGELOG.md)
-for detailed changes.
+Please refer to the [Changelog][action-mailer] for detailed changes.
### Notable changes
@@ -132,8 +170,32 @@ Please refer to the
[Changelog](https://github.com/rails/rails/blob/4-2-stable/activerecord/CHANGELOG.md)
for detailed changes.
+### Removals
+
+* Removed deprecated method `ActiveRecord::Base.quoted_locking_column`.
+ ([Pull Request](https://github.com/rails/rails/pull/15612))
+
+* Removed deprecated `ActiveRecord::Migrator.proper_table_name`. Use the
+ `proper_table_name` instance method on `ActiveRecord::Migration` instead.
+ ([Pull Request](https://github.com/rails/rails/pull/15512))
+
+* Removed `cache_attributes` and friends. All attributes are cached.
+ ([Pull Request](https://github.com/rails/rails/pull/15429))
+
+* Removed unused `:timestamp` type. Transparently alias it to `:datetime`
+ in all cases. Fixes inconsistencies when column types are sent outside of
+ `ActiveRecord`, such as for XML Serialization.
+ ([Pull Request](https://github.com/rails/rails/pull/15184))
+
### Deprecations
+* Deprecated returning `nil` from `column_for_attribute` when no column exists.
+ It will return a null object in Rails 5.0
+ ([Pull Request](https://github.com/rails/rails/pull/15878))
+
+* Deprecated `serialized_attributes` without replacement.
+ ([Pull Request](https://github.com/rails/rails/pull/15704))
+
* Deprecated using `.joins`, `.preload` and `.eager_load` with associations that
depends on the instance state (i.e. those defined with a scope that takes an
argument) without replacement.
@@ -156,6 +218,12 @@ for detailed changes.
([Commit](https://github.com/rails/rails/commit/91949e48cf41af9f3e4ffba3e5eecf9b0a08bfc3))
+* Deprecated broken support for automatic detection of counter caches on
+ `has_many :through` associations. You should instead manually specify the
+ counter cache on the `has_many` and `belongs_to` associations for the through
+ records.
+ ([Pull Request](https://github.com/rails/rails/pull/15754))
+
### Notable changes
* Added support for `#pretty_print` in `ActiveRecord::Base` objects.
@@ -186,12 +254,19 @@ for detailed changes.
* Added support for user-created range types in PostgreSQL adapter.
([Commit](https://github.com/rails/rails/commit/4cb47167e747e8f9dc12b0ddaf82bdb68c03e032))
+* Added a `:required` option to singular associations, which defines a
+ presence validation on the association.
+ ([Pull Request](https://github.com/rails/rails/pull/16056))
+
Active Model
------------
-Please refer to the
-[Changelog](https://github.com/rails/rails/blob/4-2-stable/activemodel/CHANGELOG.md)
-for detailed changes.
+Please refer to the [Changelog][active-model] for detailed changes.
+
+### Removals
+
+* Removed deprecated `Validator#setup` without replacement.
+ ([Pull Request](https://github.com/rails/rails/pull/15617))
### Notable changes
@@ -202,9 +277,7 @@ for detailed changes.
Active Support
--------------
-Please refer to the
-[Changelog](https://github.com/rails/rails/blob/4-2-stable/activesupport/CHANGELOG.md)
-for detailed changes.
+Please refer to the [Changelog][active-support] for detailed changes.
### Removals
@@ -234,6 +307,11 @@ for detailed changes.
as well as `Kernel#concern` to avoid the `module Foo; extend ActiveSupport::Concern; end`
boilerplate. ([Commit](https://github.com/rails/rails/commit/b16c36e688970df2f96f793a759365b248b582ad))
+* Added `Hash#transform_values` and `Hash#transform_values!` to simplify a
+ common pattern where the values of a hash must change, but the keys are left
+ the same.
+ ([Pull Request](https://github.com/rails/rails/pull/15819))
+
Credits
-------
@@ -241,3 +319,11 @@ 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/4-2-stable/railties/CHANGELOG.md
+[action-pack]: https://github.com/rails/rails/blob/4-2-stable/actionpack/CHANGELOG.md
+[action-view]: https://github.com/rails/rails/blob/4-2-stable/actionview/CHANGELOG.md
+[action-mailer]: https://github.com/rails/rails/blob/4-2-stable/actionmailer/CHANGELOG.md
+[active-record]: https://github.com/rails/rails/blob/4-2-stable/activerecord/CHANGELOG.md
+[active-model]: https://github.com/rails/rails/blob/4-2-stable/activemodel/CHANGELOG.md
+[active-support]: https://github.com/rails/rails/blob/4-2-stable/activesupport/CHANGELOG.md