diff options
Diffstat (limited to 'activerecord/lib/active_record/enum.rb')
| -rw-r--r-- | activerecord/lib/active_record/enum.rb | 92 |
1 files changed, 84 insertions, 8 deletions
diff --git a/activerecord/lib/active_record/enum.rb b/activerecord/lib/active_record/enum.rb index c34fc086e2..f053372cfb 100644 --- a/activerecord/lib/active_record/enum.rb +++ b/activerecord/lib/active_record/enum.rb @@ -1,3 +1,5 @@ +require 'active_support/core_ext/object/deep_dup' + module ActiveRecord # Declare an enum attribute where the values map to integers in the database, # but can be queried by name. Example: @@ -25,8 +27,10 @@ module ActiveRecord # conversation.status # => nil # # Scopes based on the allowed values of the enum field will be provided - # as well. With the above example, it will create an +active+ and +archived+ - # scope. + # as well. With the above example: + # + # Conversation.active + # Conversation.archived # # You can set the default value from the database declaration, like: # @@ -54,14 +58,27 @@ module ActiveRecord # remove unused values, the explicit +Hash+ syntax should be used. # # In rare circumstances you might need to access the mapping directly. - # The mappings are exposed through a constant with the attributes name: + # The mappings are exposed through a class method with the pluralized attribute + # name: # # Conversation.statuses # => { "active" => 0, "archived" => 1 } # - # Use that constant when you need to know the ordinal value of an enum: + # Use that class method when you need to know the ordinal value of an enum: # # Conversation.where("status <> ?", Conversation.statuses[:archived]) + # + # Where conditions on an enum attribute must use the ordinal value of an enum. module Enum + def self.extended(base) # :nodoc: + base.class_attribute(:defined_enums) + base.defined_enums = {} + end + + def inherited(base) # :nodoc: + base.defined_enums = defined_enums.deep_dup + super + end + def enum(definitions) klass = self definitions.each do |name, values| @@ -70,10 +87,12 @@ module ActiveRecord name = name.to_sym # def self.statuses statuses end + detect_enum_conflict!(name, name.to_s.pluralize, true) klass.singleton_class.send(:define_method, name.to_s.pluralize) { enum_values } _enum_methods_module.module_eval do # def status=(value) self[:status] = statuses[value] end + klass.send(:detect_enum_conflict!, name, "#{name}=") define_method("#{name}=") { |value| if enum_values.has_key?(value) || value.blank? self[name] = enum_values[value] @@ -88,35 +107,92 @@ module ActiveRecord } # def status() statuses.key self[:status] end + klass.send(:detect_enum_conflict!, name, name) define_method(name) { enum_values.key self[name] } # def status_before_type_cast() statuses.key self[:status] end + klass.send(:detect_enum_conflict!, name, "#{name}_before_type_cast") define_method("#{name}_before_type_cast") { enum_values.key self[name] } pairs = values.respond_to?(:each_pair) ? values.each_pair : values.each_with_index pairs.each do |value, i| enum_values[value] = i - # scope :active, -> { where status: 0 } - klass.scope value, -> { klass.where name => i } - # def active?() status == 0 end + klass.send(:detect_enum_conflict!, name, "#{value}?") define_method("#{value}?") { self[name] == i } # def active!() update! status: :active end + klass.send(:detect_enum_conflict!, name, "#{value}!") define_method("#{value}!") { update! name => value } + + # scope :active, -> { where status: 0 } + klass.send(:detect_enum_conflict!, name, value, true) + klass.scope value, -> { klass.where name => i } end end + defined_enums[name.to_s] = enum_values end end private def _enum_methods_module @_enum_methods_module ||= begin - mod = Module.new + mod = Module.new do + private + def save_changed_attribute(attr_name, old) + if (mapping = self.class.defined_enums[attr_name.to_s]) + value = _read_attribute(attr_name) + if attribute_changed?(attr_name) + if mapping[old] == value + clear_attribute_changes([attr_name]) + end + else + if old != value + set_attribute_was(attr_name, mapping.key(old)) + end + end + else + super + end + end + end include mod mod end end + + ENUM_CONFLICT_MESSAGE = \ + "You tried to define an enum named \"%{enum}\" on the model \"%{klass}\", but " \ + "this will generate a %{type} method \"%{method}\", which is already defined " \ + "by %{source}." + + def detect_enum_conflict!(enum_name, method_name, klass_method = false) + if klass_method && dangerous_class_method?(method_name) + raise ArgumentError, ENUM_CONFLICT_MESSAGE % { + enum: enum_name, + klass: self.name, + type: 'class', + method: method_name, + source: 'Active Record' + } + elsif !klass_method && dangerous_attribute_method?(method_name) + raise ArgumentError, ENUM_CONFLICT_MESSAGE % { + enum: enum_name, + klass: self.name, + type: 'instance', + method: method_name, + source: 'Active Record' + } + elsif !klass_method && method_defined_within?(method_name, _enum_methods_module, Module) + raise ArgumentError, ENUM_CONFLICT_MESSAGE % { + enum: enum_name, + klass: self.name, + type: 'instance', + method: method_name, + source: 'another enum' + } + end + end end end |