diff options
Diffstat (limited to 'activerecord')
| -rw-r--r-- | activerecord/lib/active_record/inheritance.rb | 46 | ||||
| -rw-r--r-- | activerecord/test/cases/dirty_test.rb | 6 |
2 files changed, 37 insertions, 15 deletions
diff --git a/activerecord/lib/active_record/inheritance.rb b/activerecord/lib/active_record/inheritance.rb index f3fe610c09..77cfb36b25 100644 --- a/activerecord/lib/active_record/inheritance.rb +++ b/activerecord/lib/active_record/inheritance.rb @@ -104,21 +104,47 @@ module ActiveRecord end end - # Set this to true if this is an abstract class (see <tt>abstract_class?</tt>). - # If you are using inheritance with ActiveRecord and don't want child classes - # to utilize the implied STI table name of the parent class, this will need to be true. - # For example, given the following: + # Set this to +true+ if this is an abstract class (see + # <tt>abstract_class?</tt>). + # If you are using inheritance with Active Record and don't want a class + # to be considered as part of the STI hierarchy, you must set this to + # true. + # +ApplicationRecord+, for example, is generated as an abstract class. # - # class SuperClass < ActiveRecord::Base + # Consider the following default behaviour: + # + # Shape = Class.new(ActiveRecord::Base) + # Polygon = Class.new(Shape) + # Square = Class.new(Polygon) + # + # Shape.table_name # => "shapes" + # Polygon.table_name # => "shapes" + # Square.table_name # => "shapes" + # Shape.create! # => #<Shape id: 1, type: nil> + # Polygon.create! # => #<Polygon id: 2, type: "Polygon"> + # Square.create! # => #<Square id: 3, type: "Square"> + # + # However, when using <tt>abstract_class</tt>, +Shape+ is omitted from + # the hierarchy: + # + # class Shape < ActiveRecord::Base # self.abstract_class = true # end - # class Child < SuperClass - # self.table_name = 'the_table_i_really_want' - # end - # + # Polygon = Class.new(Shape) + # Square = Class.new(Polygon) # - # <tt>self.abstract_class = true</tt> is required to make <tt>Child<.find,.create, or any Arel method></tt> use <tt>the_table_i_really_want</tt> instead of a table called <tt>super_classes</tt> + # Shape.table_name # => nil + # Polygon.table_name # => "polygons" + # Square.table_name # => "polygons" + # Shape.create! # => NotImplementedError: Shape is an abstract class and cannot be instantiated. + # Polygon.create! # => #<Polygon id: 1, type: nil> + # Square.create! # => #<Square id: 2, type: "Square"> # + # Note that in the above example, to disallow the creation of a plain + # +Polygon+, you should use <tt>validates :type, presence: true</tt>, + # instead of setting it as an abstract class. This way, +Polygon+ will + # stay in the hierarchy, and Active Record will continue to correctly + # derive the table name. attr_accessor :abstract_class # Returns whether this class is an abstract class or not. diff --git a/activerecord/test/cases/dirty_test.rb b/activerecord/test/cases/dirty_test.rb index 0791811d94..2f1434b2bc 100644 --- a/activerecord/test/cases/dirty_test.rb +++ b/activerecord/test/cases/dirty_test.rb @@ -737,9 +737,7 @@ class DirtyTest < ActiveRecord::TestCase end test "virtual attributes are not written with partial_writes off" do - original_partial_writes = ActiveRecord::Base.partial_writes - begin - ActiveRecord::Base.partial_writes = false + with_partial_writes(ActiveRecord::Base, false) do klass = Class.new(ActiveRecord::Base) do self.table_name = "people" attribute :non_persisted_attribute, :string @@ -753,8 +751,6 @@ class DirtyTest < ActiveRecord::TestCase record.non_persisted_attribute_will_change! assert record.save - ensure - ActiveRecord::Base.partial_writes = original_partial_writes end end |