lecture 12 of 150 completed

The test that only fails on the build server

A step-by-step method for the failure you cannot reproduce on your own machine.

What you'll learn

How to investigate a failure you cannot reproduce
How to tell an environment problem from a test problem
What evidence to collect before you need it

This will happen to you, probably in your first month. A test fails on the build server about once in ten runs. On your machine it passes every time. Someone re-runs the build, it goes green, and everyone moves on.

Do not move on. Here is the method.

Step 1. Make it fail for you.

You cannot fix something you cannot see. Run that one test many times:

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Keep reading with the full course

The Foundations track and the first lessons in each framework are free. This lesson needs full course access. A course plan includes all lessons for Playwright, Cypress and Selenium.

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