diff options
Diffstat (limited to 'activemodel/lib/active_model/attribute_methods.rb')
| -rw-r--r-- | activemodel/lib/active_model/attribute_methods.rb | 106 |
1 files changed, 55 insertions, 51 deletions
diff --git a/activemodel/lib/active_model/attribute_methods.rb b/activemodel/lib/active_model/attribute_methods.rb index af11da1351..ea07c5c039 100644 --- a/activemodel/lib/active_model/attribute_methods.rb +++ b/activemodel/lib/active_model/attribute_methods.rb @@ -1,3 +1,5 @@ +require 'thread_safe' +require 'mutex_m' module ActiveModel # Raised when an attribute is not defined. @@ -11,19 +13,23 @@ module ActiveModel # # => ActiveModel::MissingAttributeError: missing attribute: user_id class MissingAttributeError < NoMethodError end - # == Active \Model Attribute Methods + + # == Active \Model \Attribute \Methods # - # <tt>ActiveModel::AttributeMethods</tt> provides a way to add prefixes and - # suffixes to your methods as well as handling the creation of Active Record - # like class methods such as +table_name+. + # Provides a way to add prefixes and suffixes to your methods as + # well as handling the creation of <tt>ActiveRecord::Base</tt>-like + # class methods such as +table_name+. # - # The requirements to implement ActiveModel::AttributeMethods are to: + # The requirements to implement <tt>ActiveModel::AttributeMethods</tt> are to: # - # * <tt>include ActiveModel::AttributeMethods</tt> in your object. - # * Call each Attribute Method module method you want to add, such as - # +attribute_method_suffix+ or +attribute_method_prefix+. + # * <tt>include ActiveModel::AttributeMethods</tt> in your class. + # * Call each of its method you want to add, such as +attribute_method_suffix+ + # or +attribute_method_prefix+. # * Call +define_attribute_methods+ after the other methods are called. # * Define the various generic +_attribute+ methods that you have declared. + # * Define an +attributes+ method which returns a hash with each + # attribute name in your model as hash key and the attribute value as hash value. + # Hash keys must be strings. # # A minimal implementation could be: # @@ -37,6 +43,10 @@ module ActiveModel # # attr_accessor :name # + # def attributes + # { 'name' => @name } + # end + # # private # # def attribute_contrived?(attr) @@ -51,13 +61,6 @@ module ActiveModel # send("#{attr}=", 'Default Name') # end # end - # - # Note that whenever you include ActiveModel::AttributeMethods in your class, - # it requires you to implement an +attributes+ method which returns a hash - # with each attribute name in your model as hash key and the attribute value as - # hash value. - # - # Hash keys must be strings. module AttributeMethods extend ActiveSupport::Concern @@ -165,20 +168,19 @@ module ActiveModel # private # # def reset_attribute_to_default!(attr) - # ... + # send("#{attr}=", 'Default Name') # end # end # # person = Person.new # person.name # => 'Gem' # person.reset_name_to_default! - # person.name # => 'Gemma' + # person.name # => 'Default Name' def attribute_method_affix(*affixes) self.attribute_method_matchers += affixes.map! { |affix| AttributeMethodMatcher.new prefix: affix[:prefix], suffix: affix[:suffix] } undefine_attribute_methods end - # Allows you to make aliases for attributes. # # class Person @@ -212,6 +214,16 @@ module ActiveModel end end + # Is +new_name+ an alias? + def attribute_alias?(new_name) + attribute_aliases.key? new_name.to_s + end + + # Returns the original name for the alias +name+ + def attribute_alias(name) + attribute_aliases[name.to_s] + end + # Declares the attributes that should be prefixed and suffixed by # ActiveModel::AttributeMethods. # @@ -233,7 +245,7 @@ module ActiveModel # private # # def clear_attribute(attr) - # ... + # send("#{attr}=", nil) # end # end def define_attribute_methods(*attr_names) @@ -316,9 +328,10 @@ module ActiveModel attribute_method_matchers_cache.clear end - # Returns true if the attribute methods defined have been generated. def generated_attribute_methods #:nodoc: - @generated_attribute_methods ||= Module.new.tap { |mod| include mod } + @generated_attribute_methods ||= Module.new { + extend Mutex_m + }.tap { |mod| include mod } end protected @@ -331,23 +344,23 @@ module ActiveModel # invoked often in a typical rails, both of which invoke the method # +match_attribute_method?+. The latter method iterates through an # array doing regular expression matches, which results in a lot of - # object creations. Most of the times it returns a +nil+ match. As the + # object creations. Most of the time it returns a +nil+ match. As the # match result is always the same given a +method_name+, this cache is # used to alleviate the GC, which ultimately also speeds up the app # significantly (in our case our test suite finishes 10% faster with # this cache). def attribute_method_matchers_cache #:nodoc: - @attribute_method_matchers_cache ||= {} + @attribute_method_matchers_cache ||= ThreadSafe::Cache.new(initial_capacity: 4) end def attribute_method_matcher(method_name) #:nodoc: - attribute_method_matchers_cache.fetch(method_name) do |name| + attribute_method_matchers_cache.compute_if_absent(method_name) do # Must try to match prefixes/suffixes first, or else the matcher with no prefix/suffix # will match every time. matchers = attribute_method_matchers.partition(&:plain?).reverse.flatten(1) match = nil - matchers.detect { |method| match = method.match(name) } - attribute_method_matchers_cache[name] = match + matchers.detect { |method| match = method.match(method_name) } + match end end @@ -382,14 +395,6 @@ module ActiveModel AttributeMethodMatch = Struct.new(:target, :attr_name, :method_name) def initialize(options = {}) - if options[:prefix] == '' || options[:suffix] == '' - message = "Specifying an empty prefix/suffix for an attribute method is no longer " \ - "necessary. If the un-prefixed/suffixed version of the method has not been " \ - "defined when `define_attribute_methods` is called, it will be defined " \ - "automatically." - ActiveSupport::Deprecation.warn message - end - @prefix, @suffix = options.fetch(:prefix, ''), options.fetch(:suffix, '') @regex = /^(?:#{Regexp.escape(@prefix)})(.*)(?:#{Regexp.escape(@suffix)})$/ @method_missing_target = "#{@prefix}attribute#{@suffix}" @@ -412,17 +417,16 @@ module ActiveModel end end - # Allows access to the object attributes, which are held in the - # <tt>@attributes</tt> hash, as though they were first-class methods. So a - # Person class with a name attribute can use Person#name and Person#name= - # and never directly use the attributes hash -- except for multiple assigns - # with ActiveRecord#attributes=. A Milestone class can also ask - # Milestone#completed? to test that the completed attribute is not +nil+ - # or 0. + # Allows access to the object attributes, which are held in the hash + # returned by <tt>attributes</tt>, as though they were first-class + # methods. So a +Person+ class with a +name+ attribute can for example use + # <tt>Person#name</tt> and <tt>Person#name=</tt> and never directly use + # the attributes hash -- except for multiple assigns with + # <tt>ActiveRecord::Base#attributes=</tt>. # - # It's also possible to instantiate related objects, so a Client class - # belonging to the clients table with a +master_id+ foreign key can - # instantiate master through Client#master. + # It's also possible to instantiate related objects, so a <tt>Client</tt> + # class belonging to the +clients+ table with a +master_id+ foreign key + # can instantiate master through <tt>Client#master</tt>. def method_missing(method, *args, &block) if respond_to_without_attributes?(method, true) super @@ -432,17 +436,17 @@ module ActiveModel end end - # attribute_missing is like method_missing, but for attributes. When method_missing is - # called we check to see if there is a matching attribute method. If so, we call - # attribute_missing to dispatch the attribute. This method can be overloaded to - # customise the behaviour. + # +attribute_missing+ is like +method_missing+, but for attributes. When + # +method_missing+ is called we check to see if there is a matching + # attribute method. If so, we tell +attribute_missing+ to dispatch the + # attribute. This method can be overloaded to customize the behavior. def attribute_missing(match, *args, &block) __send__(match.target, match.attr_name, *args, &block) end - # A Person object with a name attribute can ask <tt>person.respond_to?(:name)</tt>, - # <tt>person.respond_to?(:name=)</tt>, and <tt>person.respond_to?(:name?)</tt> - # which will all return +true+. + # A +Person+ instance with a +name+ attribute can ask + # <tt>person.respond_to?(:name)</tt>, <tt>person.respond_to?(:name=)</tt>, + # and <tt>person.respond_to?(:name?)</tt> which will all return +true+. alias :respond_to_without_attributes? :respond_to? def respond_to?(method, include_private_methods = false) if super |