diff options
Diffstat (limited to 'activerecord/lib/active_record/type/value.rb')
-rw-r--r-- | activerecord/lib/active_record/type/value.rb | 89 |
1 files changed, 46 insertions, 43 deletions
diff --git a/activerecord/lib/active_record/type/value.rb b/activerecord/lib/active_record/type/value.rb index 9456a4a56c..fc3ef5e83b 100644 --- a/activerecord/lib/active_record/type/value.rb +++ b/activerecord/lib/active_record/type/value.rb @@ -1,44 +1,46 @@ module ActiveRecord module Type - class Value # :nodoc: + class Value attr_reader :precision, :scale, :limit - # Valid options are +precision+, +scale+, and +limit+. They are only - # used when dumping schema. - def initialize(options = {}) - options.assert_valid_keys(:precision, :scale, :limit) - @precision = options[:precision] - @scale = options[:scale] - @limit = options[:limit] + def initialize(precision: nil, limit: nil, scale: nil) + @precision = precision + @scale = scale + @limit = limit end - # The simplified type that this object represents. Returns a symbol such - # as +:string+ or +:integer+ - def type; end + def type # :nodoc: + end - # Type casts a string from the database into the appropriate ruby type. - # Classes which do not need separate type casting behavior for database - # and user provided values should override +cast_value+ instead. - def type_cast_from_database(value) - type_cast(value) + # Convert a value from database input to the appropriate ruby type. The + # return value of this method will be returned from + # ActiveRecord::AttributeMethods::Read#read_attribute. The default + # implementation just calls Value#cast. + # + # +value+ The raw input, as provided from the database. + def deserialize(value) + cast(value) end # Type casts a value from user input (e.g. from a setter). This value may - # be a string from the form builder, or an already type cast value - # provided manually to a setter. + # be a string from the form builder, or a ruby object passed to a setter. + # There is currently no way to differentiate between which source it came + # from. + # + # The return value of this method will be returned from + # ActiveRecord::AttributeMethods::Read#read_attribute. See also: + # Value#cast_value. # - # Classes which do not need separate type casting behavior for database - # and user provided values should override +type_cast+ or +cast_value+ - # instead. - def type_cast_from_user(value) - type_cast(value) + # +value+ The raw input, as provided to the attribute setter. + def cast(value) + cast_value(value) unless value.nil? end # Cast a value from the ruby type to a type that the database knows how # to understand. The returned value from this method should be a # +String+, +Numeric+, +Date+, +Time+, +Symbol+, +true+, +false+, or - # +nil+ - def type_cast_for_database(value) + # +nil+. + def serialize(value) value end @@ -50,17 +52,10 @@ module ActiveRecord # These predicates are not documented, as I need to look further into # their use, and see if they can be removed entirely. - def number? # :nodoc: - false - end - def binary? # :nodoc: false end - def klass # :nodoc: - end - # Determines whether a value has changed for dirty checking. +old_value+ # and +new_value+ will always be type-cast. Types should not need to # override this method. @@ -69,10 +64,23 @@ module ActiveRecord end # Determines whether the mutable value has been modified since it was - # read. Returns +false+ by default. This method should not be overridden - # directly. Types which return a mutable value should include - # +Type::Mutable+, which will define this method. - def changed_in_place?(*) + # read. Returns +false+ by default. If your type returns an object + # which could be mutated, you should override this method. You will need + # to either: + # + # - pass +new_value+ to Value#serialize and compare it to + # +raw_old_value+ + # + # or + # + # - pass +raw_old_value+ to Value#deserialize and compare it to + # +new_value+ + # + # +raw_old_value+ The original value, before being passed to + # +deserialize+. + # + # +new_value+ The current value, after type casting. + def changed_in_place?(raw_old_value, new_value) false end @@ -85,14 +93,9 @@ module ActiveRecord private - def type_cast(value) - cast_value(value) unless value.nil? - end - # Convenience method for types which do not need separate type casting - # behavior for user and database inputs. Called by - # `type_cast_from_database` and `type_cast_from_user` for all values - # except `nil`. + # behavior for user and database inputs. Called by Value#cast for + # values except +nil+. def cast_value(value) # :doc: value end |