Module: ActiveRecord::AttributeMethods::ClassMethods
- Defined in:
- lib/active_record/attribute_methods.rb
Instance Method Summary collapse
-
#attribute_method?(attribute) ⇒ Boolean
Returns
true
ifattribute
is an attribute method and table exists,false
otherwise. -
#attribute_methods_generated? ⇒ Boolean
:nodoc:.
-
#attribute_names ⇒ Object
Returns an array of column names as strings if it’s not an abstract class and table exists.
-
#dangerous_attribute_method?(name) ⇒ Boolean
A method name is ‘dangerous’ if it is already defined by Active Record, but not by any ancestors.
-
#define_attribute_methods ⇒ Object
Generates all the attribute related methods for columns in the database accessors, mutators and query methods.
-
#inherited(child_class) ⇒ Object
:nodoc:.
-
#initialize_generated_modules ⇒ Object
:nodoc:.
-
#instance_method_already_implemented?(method_name) ⇒ Boolean
Raises a
ActiveRecord::DangerousAttributeError
exception when an Active Record method is defined in the model, otherwisefalse
. -
#method_defined_within?(name, klass, sup = klass.superclass) ⇒ Boolean
:nodoc:.
-
#undefine_attribute_methods ⇒ Object
:nodoc:.
Instance Method Details
#attribute_method?(attribute) ⇒ Boolean
Returns true
if attribute
is an attribute method and table exists, false
otherwise.
class Person < ActiveRecord::Base
end
Person.attribute_method?('name') # => true
Person.attribute_method?(:age=) # => true
Person.attribute_method?(:nothing) # => false
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# File 'lib/active_record/attribute_methods.rb', line 122 def attribute_method?(attribute) super || (table_exists? && column_names.include?(attribute.to_s.sub(/=$/, ''))) end |
#attribute_methods_generated? ⇒ Boolean
:nodoc:
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# File 'lib/active_record/attribute_methods.rb', line 58 def attribute_methods_generated? # :nodoc: @attribute_methods_generated end |
#attribute_names ⇒ Object
Returns an array of column names as strings if it’s not an abstract class and table exists. Otherwise it returns an empty array.
class Person < ActiveRecord::Base
end
Person.attribute_names
# => ["id", "created_at", "updated_at", "name", "age"]
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# File 'lib/active_record/attribute_methods.rb', line 134 def attribute_names @attribute_names ||= if !abstract_class? && table_exists? column_names else [] end end |
#dangerous_attribute_method?(name) ⇒ Boolean
A method name is ‘dangerous’ if it is already defined by Active Record, but not by any ancestors. (So ‘puts’ is not dangerous but ‘save’ is.)
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# File 'lib/active_record/attribute_methods.rb', line 97 def dangerous_attribute_method?(name) # :nodoc: method_defined_within?(name, Base) end |
#define_attribute_methods ⇒ Object
Generates all the attribute related methods for columns in the database accessors, mutators and query methods.
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# File 'lib/active_record/attribute_methods.rb', line 47 def define_attribute_methods # :nodoc: # Use a mutex; we don't want two thread simultaneously trying to define # attribute methods. generated_attribute_methods.synchronize do return if attribute_methods_generated? superclass.define_attribute_methods unless self == base_class super(column_names) @attribute_methods_generated = true end end |
#inherited(child_class) ⇒ Object
:nodoc:
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# File 'lib/active_record/attribute_methods.rb', line 23 def inherited(child_class) #:nodoc: child_class.initialize_generated_modules super end |
#initialize_generated_modules ⇒ Object
:nodoc:
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# File 'lib/active_record/attribute_methods.rb', line 28 def initialize_generated_modules # :nodoc: @generated_attribute_methods = Module.new { extend Mutex_m const_set :AttrNames, Module.new { def self.set_name_cache(name, value) const_name = "ATTR_#{name}" unless const_defined? const_name const_set const_name, value.dup.freeze end end } } @attribute_methods_generated = false include @generated_attribute_methods end |
#instance_method_already_implemented?(method_name) ⇒ Boolean
Raises a ActiveRecord::DangerousAttributeError
exception when an Active Record method is defined in the model, otherwise false
.
class Person < ActiveRecord::Base
def save
'already defined by Active Record'
end
end
Person.instance_method_already_implemented?(:save)
# => ActiveRecord::DangerousAttributeError: save is defined by ActiveRecord
Person.instance_method_already_implemented?(:name)
# => false
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# File 'lib/active_record/attribute_methods.rb', line 81 def instance_method_already_implemented?(method_name) if dangerous_attribute_method?(method_name) raise DangerousAttributeError, "#{method_name} is defined by Active Record" end if superclass == Base super else # If B < A and A defines its own attribute method, then we don't want to overwrite that. defined = method_defined_within?(method_name, superclass, superclass.generated_attribute_methods) defined && !ActiveRecord::Base.method_defined?(method_name) || super end end |
#method_defined_within?(name, klass, sup = klass.superclass) ⇒ Boolean
:nodoc:
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# File 'lib/active_record/attribute_methods.rb', line 101 def method_defined_within?(name, klass, sup = klass.superclass) # :nodoc: if klass.method_defined?(name) || klass.private_method_defined?(name) if sup.method_defined?(name) || sup.private_method_defined?(name) klass.instance_method(name).owner != sup.instance_method(name).owner else true end else false end end |
#undefine_attribute_methods ⇒ Object
:nodoc:
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# File 'lib/active_record/attribute_methods.rb', line 62 def undefine_attribute_methods # :nodoc: super if attribute_methods_generated? @attribute_methods_generated = false end |