Test-Driven Development with Python, 3rd Edition

Chapter 6. Improving Functional Tests: Ensuring Isolation and Removing Voodoo Sleeps

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Before we dive in and fix our single-global-list problem, let’s take care of a couple of housekeeping items. At the end of the last chapter, we made a note that different test runs were interfering with each other, so we’ll fix that. I’m also not happy with all these time.sleeps peppered through the code; they seem a bit unscientific, so we’ll replace them with something more reliable.

• Clean up after FT runs

• Remove time.sleeps

Both of these changes will be moving us towards testing “best practices”, making our tests more deterministic and more reliable.

Ensuring Test Isolation in Functional Tests

We ended the last chapter with a classic testing problem: how to ensure isolation between tests. Each run of our functional tests was leaving list items lying around in the database, and that would interfere with the test results ...