RspecModelValidations

Extra matchers to improve testing of model validation

Testing model validation can be a bit clunky:

model.valid? test the entire model so it can lead to errors
specific error on attribute can be test with model.added? or errors[:attribute] but options or message must be provided
attribute setting and validation trigger must be call
as validation are test through "raw code" failure message can be hard to understand

rspec_model_validations make testing smoother by adding matchers to focus test on specific attribute / validation.

  # model
  validates :attribute, numericality: true

  # spec
  expect(model).to invalidate(:attribute).with(:blank, :not_a_number).on nil

  # equivalent to
  model.attribute = nil
  model.validate
  expect(model.errors).to be_added :attribute, :blank
  expect(model.errors).to be_added :attribute, :not_a_number, value: nil

Requirements

~> 1.0: rails ~> 7.0

Note: it should be able to run with older version of rails but behaviour is not garanted.

Installation

Add this gem to your application in :test env

  gem 'rspec_model_validations', '~> 1.0', require: false, group: :test

Setup spec/rails_helper.rb file to access matchers

  # Add additional requires below this line. Rails is not loaded until this point!
  require 'rspec_model_validations'

  # ...

  RSpec.configure do |config|
    config.include RspecModelValidations::Matchers
  end

Usage

Test validation errors

invalidate :attribute test errors on a specific attribute. It run validation and test that the targeted attribute have at least one error.

  model.attribute = nil
  expect(model).to invalidate :attribute

  # equivalent to
  model.attribute = nil
  model.validate
  expect(model.errors[:attribute]).to be_present

Options:

with specify which errors type must be present. It accept single or multiple symbols.

  model.attribute = nil
  expect(model).to invalidate(:attribute).with :blank, :not_a_number

  # equivalent to
  model.attribute = nil
  model.validate
  expect(model.errors.group_by_attribute(:attribute).map(&:type)).to include(:blank, :not_a_number)

on set the attribute value

  expect(model).to invalidate(:attribute).on nil

  # equivalent to
  model.attribute = nil
  model.validate
  expect(model.errors[:attribute]).to be_present

Test successfull validation

validate :attribute test a specific attribute validity. It run validation and then test that none errors are related to the given attribute.

  model.attribute = 9
  expect(model).to validate :attribute

  # equivalent to
  model.attribute = 9
  model.validate
  expect(model.errors[:attribute]).to be_empty

Options:

on see invalidate on option