Destructive Testing

"Is this a dagger which I see before me,

The handle toward my hand?"

- William Shakespeare, The Tragedy of Macbeth, Act 2, Scene 1

Destructive testing is a great way to find defects. By deliberately triggering specific errors, subsequent problems often occur. Even more so than error testing, as covered in Chapter 7, Testing of Error Cases, destructive testing gives you the chance to take the system out of its usual modes of operation to check its subsequent behavior.

These tests cover disabling communication with remote systems to check on retries and recovery. Your system cannot guarantee it will ever receive a reply to a message, so these scenarios need to be checked. Some subsystems are designed to be redundant, so we also consider testing that resilience. Disabling other subsystems will cause functional failures, so this measures their extent and recovery. Unfortunately, failures in remote systems will happen one day, so checking their...