diff options
Diffstat (limited to 'activemodel/lib/active_model/attribute_methods.rb')
| -rw-r--r-- | activemodel/lib/active_model/attribute_methods.rb | 127 |
1 files changed, 92 insertions, 35 deletions
diff --git a/activemodel/lib/active_model/attribute_methods.rb b/activemodel/lib/active_model/attribute_methods.rb index 16fcf14009..f30d00b355 100644 --- a/activemodel/lib/active_model/attribute_methods.rb +++ b/activemodel/lib/active_model/attribute_methods.rb @@ -3,32 +3,32 @@ require 'active_support/core_ext/class/attribute' require 'active_support/deprecation' module ActiveModel + # Raised when an attribute is not defined. class MissingAttributeError < NoMethodError end # == 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+. + # <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+. # # The requirements to implement ActiveModel::AttributeMethods are to: # - # * <tt>include ActiveModel::AttributeMethods</tt> in your object + # * <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 - # * Call <tt>define_attribute_methods</tt> after the other methods are - # called. - # * Define the various generic +_attribute+ methods that you have declared + # +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. # # A minimal implementation could be: # # class Person # include ActiveModel::AttributeMethods # - # attribute_method_affix :prefix => 'reset_', :suffix => '_to_default!' + # attribute_method_affix prefix: 'reset_', suffix: '_to_default!' # attribute_method_suffix '_contrived?' # attribute_method_prefix 'clear_' - # define_attribute_methods 'name' + # define_attribute_methods :name # # attr_accessor :name # @@ -43,17 +43,16 @@ module ActiveModel # end # # def reset_attribute_to_default!(attr) - # send("#{attr}=", "Default Name") + # send("#{attr}=", 'Default Name') # end # end # # Note that whenever you include ActiveModel::AttributeMethods in your class, - # it requires you to implement an <tt>attributes</tt> method which returns a hash + # 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 @@ -79,11 +78,9 @@ module ActiveModel # An instance method <tt>#{prefix}attribute</tt> must exist and accept # at least the +attr+ argument. # - # For example: - # # class Person - # # include ActiveModel::AttributeMethods + # # attr_accessor :name # attribute_method_prefix 'clear_' # define_attribute_methods :name @@ -96,7 +93,7 @@ module ActiveModel # end # # person = Person.new - # person.name = "Bob" + # person.name = 'Bob' # person.name # => "Bob" # person.clear_name # person.name # => nil @@ -114,14 +111,12 @@ module ActiveModel # # attribute#{suffix}(#{attr}, *args, &block) # - # An <tt>attribute#{suffix}</tt> instance method must exist and accept at least - # the +attr+ argument. - # - # For example: + # An <tt>attribute#{suffix}</tt> instance method must exist and accept at + # least the +attr+ argument. # # class Person - # # include ActiveModel::AttributeMethods + # # attr_accessor :name # attribute_method_suffix '_short?' # define_attribute_methods :name @@ -134,7 +129,7 @@ module ActiveModel # end # # person = Person.new - # person.name = "Bob" + # person.name = 'Bob' # person.name # => "Bob" # person.name_short? # => true def attribute_method_suffix(*suffixes) @@ -155,13 +150,11 @@ module ActiveModel # An <tt>#{prefix}attribute#{suffix}</tt> instance method must exist and # accept at least the +attr+ argument. # - # For example: - # # class Person - # # include ActiveModel::AttributeMethods + # # attr_accessor :name - # attribute_method_affix :prefix => 'reset_', :suffix => '_to_default!' + # attribute_method_affix prefix: 'reset_', suffix: '_to_default!' # define_attribute_methods :name # # private @@ -184,14 +177,27 @@ module ActiveModel # Allows you to make aliases for attributes. # # class Person + # include ActiveModel::AttributeMethods + # # attr_accessor :name + # attribute_method_suffix '_short?' + # define_attribute_methods :name + # # alias_attribute :nickname, :name + # + # private + # + # def attribute_short?(attr) + # send(attr).length < 5 + # end # end # # person = Person.new - # person.nickname = "Bob" - # person.nickname # => "Bob" - # person.name # => "Bob" + # person.name = 'Bob' + # person.name # => "Bob" + # person.nickname # => "Bob" + # person.name_short? # => true + # person.nickname_short? # => true def alias_attribute(new_name, old_name) self.attribute_aliases = attribute_aliases.merge(new_name.to_s => old_name.to_s) attribute_method_matchers.each do |matcher| @@ -204,13 +210,13 @@ module ActiveModel # Declares the attributes that should be prefixed and suffixed by # ActiveModel::AttributeMethods. # - # To use, pass in an array of attribute names (as strings or symbols), - # be sure to declare +define_attribute_methods+ after you define any - # prefix, suffix or affix methods, or they will not hook in. + # To use, pass attribute names (as strings or symbols), be sure to declare + # +define_attribute_methods+ after you define any prefix, suffix or affix + # methods, or they will not hook in. # # class Person - # # include ActiveModel::AttributeMethods + # # attr_accessor :name, :age, :address # attribute_method_prefix 'clear_' # @@ -229,6 +235,35 @@ module ActiveModel attr_names.flatten.each { |attr_name| define_attribute_method(attr_name) } end + # Declares an attribute that should be prefixed and suffixed by + # ActiveModel::AttributeMethods. + # + # To use, pass an attribute name (as string or symbol), be sure to declare + # +define_attribute_method+ after you define any prefix, suffix or affix + # method, or they will not hook in. + # + # class Person + # include ActiveModel::AttributeMethods + # + # attr_accessor :name + # attribute_method_suffix '_short?' + # + # # Call to define_attribute_method must appear after the + # # attribute_method_prefix, attribute_method_suffix or + # # attribute_method_affix declares. + # define_attribute_method :name + # + # private + # + # def attribute_short?(attr) + # send(attr).length < 5 + # end + # end + # + # person = Person.new + # person.name = 'Bob' + # person.name # => "Bob" + # person.name_short? # => true def define_attribute_method(attr_name) attribute_method_matchers.each do |matcher| method_name = matcher.method_name(attr_name) @@ -246,7 +281,29 @@ module ActiveModel attribute_method_matchers_cache.clear end - # Removes all the previously dynamically defined methods from the class + # Removes all the previously dynamically defined methods from the class. + # + # class Person + # include ActiveModel::AttributeMethods + # + # attr_accessor :name + # attribute_method_suffix '_short?' + # define_attribute_method :name + # + # private + # + # def attribute_short?(attr) + # send(attr).length < 5 + # end + # end + # + # person = Person.new + # person.name = 'Bob' + # person.name_short? # => true + # + # Person.undefine_attribute_methods + # + # person.name_short? # => NoMethodError def undefine_attribute_methods generated_attribute_methods.module_eval do instance_methods.each { |m| undef_method(m) } |