module ActiveModel::Lint::Tests
Active Model Lint Tests¶ ↑
You can test whether an object is compliant with the Active Model API by
including ActiveModel::Lint::Tests
in your TestCase. It will include tests that tell you
whether your object is fully compliant, or if not, which aspects of the API
are not implemented.
These tests do not attempt to determine the semantic correctness of the returned values. For instance, you could implement valid? to always return true, and the tests would pass. It is up to you to ensure that the values are semantically meaningful.
Objects you pass in are expected to return a compliant object from a call to to_model. It is perfectly fine for to_model to return self.
Public Instance Methods
Errors Testing¶ ↑
Returns an object that has :[] and :full_messages defined on it. See below for more details.
Returns an Array of Strings that are the errors for the attribute in question. If localization is used, the Strings should be localized for the current locale. If no error is present, this method should return an empty Array.
# File lib/active_model/lint.rb, line 100 def test_errors_aref assert model.respond_to?(:errors), "The model should respond to errors" assert model.errors[:hello].is_a?(Array), "errors#[] should return an Array" end
Returns an Array of all error messages for the object. Each message should contain information about the field, if applicable.
# File lib/active_model/lint.rb, line 107 def test_errors_full_messages assert model.respond_to?(:errors), "The model should respond to errors" assert model.errors.full_messages.is_a?(Array), "errors#full_messages should return an Array" end
Naming¶ ↑
Model.model_name must return a string with some convenience methods: :human, :singular, and :plural. Check ActiveModel::Naming for more information.
# File lib/active_model/lint.rb, line 82 def test_model_naming assert model.class.respond_to?(:model_name), "The model should respond to model_name" model_name = model.class.model_name assert_kind_of String, model_name assert_kind_of String, model_name.human assert_kind_of String, model_name.singular assert_kind_of String, model_name.plural end
Responds to persisted?
¶ ↑
Returns a boolean that specifies whether the object has been persisted yet. This is used when calculating the URL for an object. If the object is not persisted, a form for that object, for instance, will be POSTed to the collection. If it is persisted, a form for the object will be PUT to the URL for the object.
# File lib/active_model/lint.rb, line 72 def test_persisted? assert model.respond_to?(:persisted?), "The model should respond to persisted?" assert_boolean model.persisted?, "persisted?" end
Responds to to_key
¶ ↑
Returns an Enumerable of all (primary) key attributes or nil if model.persisted? is false
# File lib/active_model/lint.rb, line 23 def test_to_key assert model.respond_to?(:to_key), "The model should respond to to_key" def model.persisted?() false end assert model.to_key.nil?, "to_key should return nil when `persisted?` returns false" end
Responds to to_param
¶ ↑
Returns a string representing the object's key suitable for use in URLs or nil if model.persisted? is false.
Implementers can decide to either raise an exception or provide a default in case the record uses a composite primary key. There are no tests for this behavior in lint because it doesn't make sense to force any of the possible implementation strategies on the implementer. However, if the resource is not persisted?, then to_param should always return nil.
# File lib/active_model/lint.rb, line 39 def test_to_param assert model.respond_to?(:to_param), "The model should respond to to_param" def model.to_key() [1] end def model.persisted?() false end assert model.to_param.nil?, "to_param should return nil when `persisted?` returns false" end
Responds to to_partial_path
¶ ↑
Returns a string giving a relative path. This is used for looking up partials. For example, a BlogPost model might return “blog_posts/blog_post”
# File lib/active_model/lint.rb, line 51 def test_to_partial_path assert model.respond_to?(:to_partial_path), "The model should respond to to_partial_path" assert_kind_of String, model.to_partial_path end
Private Instance Methods
# File lib/active_model/lint.rb, line 118 def assert_boolean(result, name) assert result == true || result == false, "#{name} should be a boolean" end
# File lib/active_model/lint.rb, line 113 def model assert @model.respond_to?(:to_model), "The object should respond_to to_model" @model.to_model end