The build_association method was added as an API for plugins
to hook into in 1398db01. This commit restores this API and the
ability to override class.new to return a subclass based on
a virtual attribute in the attributes hash.

Don't use mass-assignment protection when setting foreign keys or association conditions on singular associations. Fixes #481 (again).

Deprecated support for passing hashes and relations to default_scope, in favour of defining a 'default_scope' class method in the model. See the CHANGELOG for more details.

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.

Add interpolation of association conditions back in, in the form of proc { ... } rather than instance_eval-ing strings

We shouldn't be using scoped.scoping { ... } to build associated records, as this can affect validations/callbacks/etc inside the record itself [#6252 state:resolved]

When assigning a has_one, if the existing record fails to be removed from the association, raise an error

has_one should always remove the old record (properly), even if not saving the new record, so we don't get the database into a pickle

Construct an actual ActiveRecord::Relation object for the association scope, rather than a hash which is passed to apply_finder_options. This allows more flexibility in how the scope is created, for example because scope.where(a, b) and scope.where(a).where(b) mean different things.

Remove undocumented feature from has_one where you could pass false as the second parameter to build_assoc or create_assoc, and the existing associated object would be untouched (the foreign key would not be nullified, and it would not be deleted). If you want behaviour similar to this you can do the following things:

* Use :dependent => :nullify (or don't specify :dependent) if you want to prevent the existing associated object from being deleted
* Use has_many if you actually want multiple associated objects
* Explicitly set the foreign key if, for some reason, you really need to have multiple objects associated with the same has_one. E.g.

    previous = obj.assoc
    obj.create_assoc
    previous.update_attributes(:obj_id => obj.id)

- persisted? is the API defined in ActiveModel
- makes it easier for extension libraries to conform to ActiveModel APIs
  without concern for whether the extended object is specifically
  ActiveRecord

[#5927 state:committed]
Signed-off-by: NSantiago Pastorino <santiago@wyeworks.com>

Signed-off-by: NSantiago Pastorino <santiago@wyeworks.com>

code gardening: we have assert_(nil|blank|present), more concise, with better default failure messages - let's use them

[#4645 state:resolved]
Signed-off-by: NJosé Valim <jose.valim@gmail.com>

Signed-off-by: Nwycats <wycats@gmail.com>

Signed-off-by: NJosé Valim <jose.valim@gmail.com>

Remove the test which was testing a non-existing method, always failing on 1.9 and never even running on 1.8

Make has_one with :conditions hash scope build or creation of the associated object with those conditions
Signed-off-by: NMichael Koziarski <michael@koziarski.com>
[#3088 state:committed]

Fix has_one with foreign_key and primary_key association bug which caused the associated object being lost when saving the owner. [#1756 state:resolved]

Mixed in a bit from patch by ransom-briggs. [#2813 state:resolved]
Signed-off-by: NEloy Duran <eloy.de.enige@gmail.com>

[#2594 state:open]

This reverts commit 99c103be.

[#2594 state:committed]
Signed-off-by: NJeremy Kemper <jeremy@bitsweat.net>

Signed-off-by: NPratik Naik <pratiknaik@gmail.com>

[#1617 state:resolved]

Ensure replacing has_one associations respects the supplied :dependent option. [#1305 state:resolved]
Signed-off-by: NPratik Naik <pratiknaik@gmail.com>

Ensure methods called on association proxies respect access control. [#1083 state:resolved] [Adam Milligan, Pratik]

Signed-off-by: NPratik Naik <pratiknaik@gmail.com>

Signed-off-by: NJoshua Peek <josh@joshpeek.com>

Add support for :primary_key option to has_one as well as has_many so that a key other than the default primary key can be used for the association
Signed-off-by: NMichael Koziarski <michael@koziarski.com>

Signed-off-by: NPratik Naik <pratiknaik@gmail.com>

Signed-off-by: NMichael Koziarski <michael@koziarski.com>
[#241 state:resolved]