A Note on Assertions per Test

You’ll often find that a common setup results in multiple assertions in a test. This is particularly true of integration tests. For example, when you wrote your initial test to add tasks back in Chapter 3, Test-Driven Rails, you made several assertions about the existence of the project and its relationship with the tasks you’d just created.

There are two contrasting styles for writing tests with multiple assertions. In one style, the setup and all the assertions are part of the same test. If you were trying to test changes when you mark a task complete, then having all the assertions in the same test might look like this:

 it ​"marks a task complete"​ ​do
  task = tasks(​:incomplete​)
  task.mark_complete

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