Class Factory: Factory_girl syntax for dynamically creating Ruby classes
Class Factory will dynamically create classes using a factories model similar to factory_girl. But instead of passing a block with model attributes into the factory definition, you pass in a migration defining the attributes of the new model class you want to create:
ClassFactory.define :person do |p|
p.string :first_name
p.string :last_name
p.integer :age
end
Now when you need a “Person” model in your tests you create one like this:
ClassFactory :person
=> Person(id: integer, first_name: string, last_name: string, age: integer)
This can be useful if you’re writing tests for a gem or plugin and don’t want to load the entire Rails environment, or have access to existing models in a target application. By default Class Factory creates ActiveRecord model classes, but using the :super option you can create any sort of Ruby class. Class Factory also makes it easy for each of your tests to use a different variation on a target class. For example, this will delete the Person model we created above, and create a new Person model that belongs to a group:
ClassFactory :person, :class_eval => 'belongs_to :group' do |p|
p.string :first_name
p.string :middle_name
p.string :last_name
p.string :group_id
end
=> Person(id: integer, first_name: string, middle_name: string, last_name: string, group_id: string)
Creating different variations of the same class can be useful if you’re writing tests for a generator, plugin or some other code which has different behavior depending on what classes you run it against.
Install
gem install class_factory
Options
Default: create a new ActiveRecord model, along with a corresponding table in your database:
ClassFactory :person
Execute a migration on the new table specified as a block, defining the attributes of the new model class:
ClassFactory :person do |p|
p.string :first_name
p.string :last_name
p.integer :age
end
Create a class with a specified superclass (default is ActiveRecord::Base):
ClassFactory :person_array, :super => Array
If SuperClass is not a subclass of ActiveRecord::Base then Class Factory won’t create a table or run a migration. You can use this to create plain Ruby object classes.
Create a class called “DifferentClass” instead of “Person:”
ClassFactory :person, :class => 'DifferentClass'
Run the given code inside the new class using class_eval:
ClassFactory :person, :class_eval => 'has_many :shoes'
Create a table with the given name, instead of a table called “people:”
ClassFactory :person, :class_eval => 'set_table_name :table_name', :table => 'table_name'
If you provide options when the factory is defined they will be applied to each class created with the factory. You can also provide options when you create a class, in which case they will override the factory options.