Module: ActiveModel::Serializer::Lint::Tests

Defined in:
lib/active_model/serializer/lint.rb

Overview

Active Model Serializer Lint Tests

You can test whether an object is compliant with the Active Model Serializers API by including ActiveModel::Serializer::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.

Note an object is not required to implement all APIs in order to work with Active Model Serializers. This module only intends to provide guidance in case you want all features out of the box.

These tests do not attempt to determine the semantic correctness of the returned values. For instance, you could implement serializable_hash to always return {}, and the tests would pass. It is up to you to ensure that the values are semantically meaningful.

Instance Method Summary collapse

Instance Method Details

#test_as_json ⇒ Object

Passes if the object responds to as_json and if it takes zero or one arguments. Fails otherwise.

as_json returns a hash representation of a serialized object. It may delegate to serializable_hash Typically, it is implemented either by including ActiveModel::Serialization which includes ActiveModel::Serializers::JSON. or by the JSON gem when required.



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# File 'lib/active_model/serializer/lint.rb', line 60

def test_as_json
  assert_respond_to resource, :as_json
  resource.as_json
  resource.as_json(nil)
end

#test_cache_key ⇒ Object

Passes if the object responds to cache_key and if it takes no arguments (Rails 4.0) or a splat (Rails 4.1+). Fails otherwise.

cache_key returns a (self-expiring) unique key for the object, which is used by the adapter. It is not required unless caching is enabled.



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# File 'lib/active_model/serializer/lint.rb', line 86

def test_cache_key
  assert_respond_to resource, :cache_key
  actual_arity = resource.method(:cache_key).arity
  # using absolute value since arity is:
  #   0 for Rails 4.1+, *timestamp_names
  #  -1 for Rails 4.0, no arguments
  assert_includes [-1, 0], actual_arity, "expected #{actual_arity.inspect} to be 0 or -1"
end

#test_id ⇒ Object

Passes if the object responds to id and if it takes no arguments. Fails otherwise.

id returns a unique identifier for the object. It is not required unless caching is enabled.



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# File 'lib/active_model/serializer/lint.rb', line 101

def test_id
  assert_respond_to resource, :id
  assert_equal resource.method(:id).arity, 0
end

#test_model_name ⇒ Object

Passes if the object’s class responds to model_name and if it is in an instance of ActiveModel::Name. Fails otherwise.

model_name returns an ActiveModel::Name instance. It is used by the serializer to identify the object’s type. It is not required unless caching is enabled.



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# File 'lib/active_model/serializer/lint.rb', line 113

def test_model_name
  resource_class = resource.class
  assert_respond_to resource_class, :model_name
  assert_instance_of resource_class.model_name, ActiveModel::Name
end

#test_read_attribute_for_serialization ⇒ Object

Passes if the object responds to read_attribute_for_serialization and if it requires one argument (the attribute to be read). Fails otherwise.

read_attribute_for_serialization gets the attribute value for serialization Typically, it is implemented by including ActiveModel::Serialization.



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# File 'lib/active_model/serializer/lint.rb', line 36

def test_read_attribute_for_serialization
  assert_respond_to resource, :read_attribute_for_serialization, 'The resource should respond to read_attribute_for_serialization'
  actual_arity = resource.method(:read_attribute_for_serialization).arity
  if defined?(::Rubinius)
    #  1 for def read_attribute_for_serialization(name); end
    # -2 for alias :read_attribute_for_serialization :send for rbx because :shrug:
    assert_includes [1, -2], actual_arity, "expected #{actual_arity.inspect} to be 1 or -2"
  else
    # using absolute value since arity is:
    #  1 for def read_attribute_for_serialization(name); end
    # -1 for alias :read_attribute_for_serialization :send
    assert_includes [1, -1], actual_arity, "expected #{actual_arity.inspect} to be 1 or -1"
  end
end

#test_serializable_hash ⇒ Object

Passes if the object responds to serializable_hash and if it takes zero or one arguments. Fails otherwise.

serializable_hash returns a hash representation of a object’s attributes. Typically, it is implemented by including ActiveModel::Serialization.



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# File 'lib/active_model/serializer/lint.rb', line 24

def test_serializable_hash
  assert_respond_to resource, :serializable_hash, 'The resource should respond to serializable_hash'
  resource.serializable_hash
  resource.serializable_hash(nil)
end

#test_to_json ⇒ Object

Passes if the object responds to to_json and if it takes zero or one arguments. Fails otherwise.

to_json returns a string representation (JSON) of a serialized object. It may be called on the result of as_json. Typically, it is implemented on all objects when the JSON gem is required.



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# File 'lib/active_model/serializer/lint.rb', line 73

def test_to_json
  assert_respond_to resource, :to_json
  resource.to_json
  resource.to_json(nil)
end