Subcutaneous Testing
If a unit test is testing the smallest testable component of application code, then a subcutaneous test is a single workflow which can be identified and tested of the application code. Subcutaneous testing treats a workflow as a testable unit.
Why subcutaneous testing over traditional unit testing?
Advantages:
- Reduced coupling between implementation and tests
- Improve ease of refactoring
- Reduce cost of evolving design
- Brings business-focus to developers
- Reduce need for brittle end-to-end tests
Disadvantages:
- More setup
- Hard to focus on a unit of work
- Debugging tests
- Decide when to add complementary unit tests is subjective
Prepare for the exercise
Install dependencies
$ yarn
Familiarize with the todos application at http://localhost:3000
$ yarn start
Run the test
$ yarn test
All the unit tests should pass.
Now Identify different workflow in the application and for each of them you will write a subcutaneous test. When you are ready to start, open the todos.workflows.spec.js and start to write your first subcutaneous test.
If you cannot identify any user workflow here are a couple to get you started:
First flow (Basic usage)
- user type a todo
- user click the add todo button
- user see the added todo in the list
- user click on todo to mark it as completed
- user see the todo marked as completed
Second flow (Visibility Filters)
- user type a todo (todo one)
- user click the add todo button
- user type another todo (todo two)
- user click the add todo button
- user click on (todo one) to mark it as completed
- user click on active filter
- user only see (todo two)
- user click on completed filter
- user only see (todo one)
- user click on all filter
- user see all todos
You can find an implementation of the subcutaneous tests in the branch named solution (only with enzyme).