The Orange Juice Test

After preparing test cases during requirements analysis, you have not completed creating tests. Your most important test often remains undiscovered until you start testing.

Imagine testing orange juice for a restaurant.


The business has provided you with a list of requirements:

  1. 8 fluid oz
  2. Cold
  3. Arrives within 2 minutes of the order

Now let's plan some requirements-based tests of what we want to check to test the orange juice.

  1. Measure the volume by pouring it into a measuring beaker
  2. Use a thermometer to measure the temperature
  3. Use a stopwatch to measure the time it took

Testing begins …


Imagine the waitress bringing out your orange juice, but it's blue!
There was no requirement for the orange juice to be a particular color. It was likely an assumption.

While it's unlikely to be served blue orange juice, it's very likely for product requirements to be assumed and missed during development.

If you are responsible for testing this orange juice glass, of course, you would immediately let everyone know. Hey! This orange juice is blue, is that supposed to happen?

Assumptions are a gap in the approaches of Test Driven Development or Behavior Driven Development with automation. They would all pass because the computer was not told to check the color. Testing exposes the unexpected.

When you are asked only to run planned tests, remember a glass of orange juice that is colored blue.