How to Split Test Inputs into Equivalence Partitions

Equivalence partitioning is a black-box testing technique used to reduce the number of test cases while maintaining effective coverage. The goal is to divide test inputs into groups or “partitions” that are expected to behave similarly, meaning that testing one input from each group is sufficient to represent the entire group.

Steps to Split Inputs into Equivalence Partitions:

1. Identify Input Domain: First, understand the input domain of the system or functionality being tested. This could involve numbers, text fields, date ranges, etc.

2. Define Valid and Invalid Ranges: After identifying the input domain, divide it into valid and invalid ranges. For example, if a field only accepts integers from 1 to 100, the valid partition is [1-100], while invalid partitions could be numbers below 1 and above 100, or non-integer values.

3. Create Test Cases: For each partition, select one representative value. If testing a login form that accepts passwords with a length of 8-20 characters, you would create one test case for a password of valid length and additional test cases for lengths below 8 and above 20.

4. Special Considerations: Consider scenarios like null values, empty strings, or special characters. These can often form their own equivalence partitions.

Benefits of Equivalence Partitioning:

• Reduces Test Effort: Instead of testing all possible inputs, testers focus on representative values.

• Increases Coverage: Ensures that both valid and invalid inputs are tested without unnecessary duplication.

Conclusion

Equivalence partitioning streamlines the testing process by identifying input classes that behave similarly. By strategically choosing test inputs, testers can ensure comprehensive coverage with fewer test cases.