Testing in Ruby on Rails

Coding in Ruby on Rails follows ‘Don’t Repeat Yourself’ and ‘Conventions over Configuration’ fundamentals of programming to reduce the application code. The code of a RoR application is clean and structured. This makes the testing and debugging tasks easy. Let’s take a deeper look in Ruby on Rails testing procedures.

Testing is essential in Ruby on Rails because the application needs to interact frequently with the database. Besides, testing is one of the necessary component in RoR application development.

Ruby on Rails comes with an in-built test framework. By default, the configuration YML file of RoR application has three unique databases named production, development, and test. This allows the developer to test the application without fear of changing the database used in the production phase.

The test database is generally destroyed during testing. However, you can build it from scratch again for testing purpose. Just run a rake db:test:prepare to build the test database.

Ruby on Rails testing architecture:

The test folder has four folders named unit, integration, functional and fixtures. The unit folder contains the test for models. The functional folder holds information about the test for controllers. The integration folder contains information about the number of controllers interacting and the fixtures folder contains information about ways of organizing the data. The test folder also contains test_helper.rb file that contains default configuration for RoR application tests.

Procedure of application testing in RoR:

In Ruby on Rails, you need to load the file containing test case in the unit folder. By default, all test methods are run in a test case. However, you can also run a single test method through the command line.

ruby unit_test.rb -> it will run all test methods in a test case
ruby unit_test.rb -n my_test_method -> it will run the test method with name my_test_method

The last line of the output is the summary of the tests. It looks like 1 test, 1 assertion, 0 failures, and 0 errors

Before the line mentioning duration of test, you can see the results of the test. A dot(.) denotes success, E denotes Error, and F denotes failure of the tests.

Ruby on Rails testing environment offers easy debugging tools. If the code has failed the tests, you can easily find fault in the code by looking at the Failure section of the tests. This section mentions the names of failing tests. All test methods in test cases execute in an alphabetical order. If the assertion fails, the execution of each method stops and generates an assertion failure message.

Unit Test:

Unit testing in Ruby on Rails is a great way to find errors in the early development phase. It allows you to check every validation using at least one test for method in the application model.

Assertions are necessary in Unit Test. They ensure things are going as planned in the code. The test/unit in Ruby on Rails comes with a full library of assertions used in Unit Test. Every assertion has a purpose. You can use assertion for different purposes such as checking equality or inequality between two objects or expressions, query matching of strings, raising exception, throwing a symbol and many other purposes.