I’ve been working through the testing trails in upcase for test doubles and testing fundamentals. The most difficult part for me was understanding mocks and spies along with how to structure them to make sure the right behavior is being tested. I’ve written unit tests and a few acceptance tests in the past but I’ve never used test doubles before the upcase trail. I had to research the differences between fakes, dummies, stubs, spies and mocks. Upcase provided an aricle by Martin Fowler as an introduction to those ideas. From my understanding, the advantages of using test doubles are clarity and speed. The unit tests should already tests that the proper answers are being given in the model or controller level which makes stubs a good way to improve them. Mocks ensure that specific method calls are being used and spies take that a step further by recording how the method calls are used. For example, spies could say that a method call was used twice instead of the expected once.

I’ve learned the definitions for different kinds of testing; unit, integration, feature, and functional tests. Unit tests are for a small subset of the application and I closely associate it with tests for a specific controller or model. Integration tests go from end to end and I’ve used it to test that logging in to an application or using the user interface. Functional tests are integration tests that actually run the application from end to end similar to making sure that an email is sent when a person is trying to recover a forgotten password. Feature tests are for things that change the functionality of the application like changing a status update from text only to including image attachments.

I’m also still getting used to rspec and capybara. The most prevalent comments I would receive from the exercises were the different shortcuts people use in their tests and other improvements on readability to make sure that the reader can better understand the intent behind the tests. Most of my tests in the past was using Minitest because it was included by default and it was the framework most of the tutorials I followed use; it’s the testing framework included with the exercism exercises and the Treehouse tutorials for the Treebook application. I’ve never really thought of tests outside unit testing but I’m appreciating what testing adds to the application. I’m starting to see why tests can function as documentation instead of comments and how bugs can be recreated to better understand where edge cases are coming from.