The One, Zero, Many heuristic is a simple tool for testing how software handles different quantities of data. This approach helps us think about system behaviour with no entries, a single entry, and multiple entries. It can be used to test anything from input fields to API responses.
To put this into practice, we’re setting an activity to help you apply this heuristic and strengthen your testing approach.
Why take part? Practicing heuristics helps you think outside the box and make decisions, improving your ability to spot edge cases and unexpected behaviours. It’s a valuable skill for both new and experienced testers.
Activity Steps: Create Test Cases
Choose a feature to test for any piece of software (e.g., a search function or input field) and write three test cases:
Zero Entries – What happens with no data?
One Entry – How does the system handle one item?
Many Entries – Can it manage multiple items correctly?
Share your test cases here! This is a great way to practice and see how others think through these scenarios.
Not sure if I’m on the right track here, example could be when searching for a flight.
Zero Routes- when the user searches a route that is not available for between 2 cities. messaging could be “no routes available, try adjusting your search criteria”
One Route- when 1 route exists that matches the users search e.g. direct flight from Melbourne > Sydney. Page should show the time/duration/stops etc and provide air travel classes (economy/business class etc) and book button
Multiple Routes- When the destination city has more than 1 airport e.g. New York City. Page should return all airport options by time/duration/stops etc. and provide air travel classes (economy/business class etc) and book button.
The page should ideally have a header at the top of page saying “showing all airports available for New York”