It has been moved to active_record_deprecated_finders.

Use #to_a instead.

Bug #6289

If a record is removed from a has_many :through, all of the join records
relating to that record should also be removed from the through
association's target.

(Previously the records were removed in the database, but only one was
removed from the in-memory target array.)

Fixes #3425.

added an alias for new to build to the AR collection proxy, this corrects an issue where the collection proxies were not consistent

singular and collection relations in AR can now specify mass-assignment security options (:as and :without_protection) in build, create and create! methods.

Associations - where possible, call attributes methods rather than directly accessing the instance variables

Split AssociationProxy into an Association class (and subclasses) which manages the association, and a CollectionProxy class which is *only* a proxy. Singular associations no longer have a proxy. See CHANGELOG for more.

Allow building and then later saving has_many :through records, such that the join record is automatically saved too. This requires the :inverse_of option to be set on the source association in the join model. See the CHANGELOG for details. [#4329 state:resolved]

Refactor the implementations of AssociatioCollection#delete and #destroy to be more consistent with each other, and to stop passing blocks around, thus making the execution easier to follow.

Correctly update counter caches on deletion for has_many :through [#2824 state:resolved]. Also fixed a bunch of other counter cache bugs in the process, as once I fixed this one others started appearing like nobody's business.

Support the :dependent option on has_many :through associations. For historical and practical reasons, :delete_all is the default deletion strategy employed by association.delete(*records), despite the fact that the default strategy is :nullify for regular has_many. Also, this only works at all if the source reflection is a belongs_to. For other situations, you should directly modify the through association.

Make record.association.destroy(*records) on habtm and hm:t only delete records in the join table. This is to make the destroy method more consistent across the different types of associations. For more details see the CHANGELOG entry.

Let AssociationCollection#find use #scoped to do its finding. Note that I am removing test_polymorphic_has_many_going_through_join_model_with_disabled_include, since this specifies different behaviour for an association than for a regular scope. It seems reasonable to expect scopes and association proxies to behave in roughly the same way rather than having subtle differences.

This required changing the code to keep the association proxy for a belongs_to around, despite its target being nil. Which in turn required various changes to the way that stale target checking is handled, in order to support various edge cases (loaded target is nil then foreign key added, foreign key is changed and then changed back, etc). A side effect is that the code is nicer and more succinct.

Note that I am removing test_no_unexpected_aliasing since that is basically checking that the proxy for a belongs_to *does* change, which is the exact opposite of the intention of this commit. Also adding various tests for various edge cases and related things.

Phew, long commit message!

Rename AssociationReflection#primary_key_name to foreign_key, since the options key which it relates to is :foreign_key

Use conditionals and implicit returns rather than explicit returns and postfix ifs (it's easier to read)

Remove has_cached_counter? and cached_counter_attribute_name from HasManyThroughAssociation, as the exact same methods are inherited from HasManyAssociation

Use the through association proxy for operations on the through record, so that those operations are automatically scoped and therefore construct_join_attributes does not need to use construct_owner_attributes.

If a has_many goes :through a belongs_to, and the foreign key of the belongs_to changes, then the has_many should be considered stale.

Delete create, create! and create_record from HasManyThroughAssociation in exchange for more generic versions in AssociationCollection

Specify insert_record with NotImplementedError in AssociationCollection, to indicate that subclasses should implement it. Also add save_record to reduce duplication.