Equivalence Class Testing

Among various testing techniques, equivalence class testing stands out as an efficient method for cutting down the number of test cases required while maintaining thorough test coverage. 

Equivalence class testing is based on the principle that inputs can be grouped into equivalence classes that exhibit similar behavior. By selecting representative test cases from these classes, testers can efficiently cover various scenarios without testing every possible input value individually. This technique is the best of both worlds, optimizing test case selection all while maintaining thorough test coverage; as those from ProfessionalQA.com put it, both the quality of test cases as well as testing as a whole is enhanced “by removing the vast amount of redundancy and gaps that appear in the boundary value testing.”

Equivalence class testing has four variations, each of which have their own benefits, downsides, and uses. They are determined using the combinations of two factors, the number of test cases and whether only valid values are tested or both valid and invalid are tested Thus, in terms of equivalence classes, we have weak-normal, strong-normal, weak-robust, and strong-robust. Weak-normal has few but effective tests and only covers the valid equivalence classes, strong-normal covers every valid equivalence class, weak-robust is like weak-normal but includes an invalid equivalence class(es) as well, and strong-robust covers every valid and invalid equivalence class. One thing to note about strong-robust equivalence class testing is that there is some redundancy when it comes to testing the invalid equivalence classes.

Equivalence class testing was a bit hard to pick up initially but it really clicked thanks to some visual aid, that being the graphs of the variations of equivalence class testing. With this visual, I was able to understand how effective equivalence class testing is and why some will want to use it. It allows testers to “focus on smaller data sets, which increases the probability to uncovering more defects in the software product” and may reduce the possibility of error on the tester’s part. With other testing techniques that are more difficult or time-consuming when it comes to larger data sets, equivalence class testing is a great alternative.

https://www.professionalqa.com/equivalence-class-testing