What is Equivalence Partitioning Testing Technique?
Equivalence Partitioning Technique is also known as Equivalence Class Partitioning or ECP. The idea behind this technique is to divide/partition a set of test conditions into groups or sets that can be considered the same or equivalence .This is used to reduce the total number of test cases to a finite set of testable test cases, still covering maximum requirements.
One test value is picked from each class while testing. This is because we are assuming that all the conditions in one partition will be treated in the same way by the software. If one condition in a partition works, we assume all of the conditions in that partition will work and if one condition fails it is assumed that all others in the partition will fail and there is no point in testing others.
Example of Equivalence Partitioning Technique
Test cases for input box accepting numbers between 1 and 1000 using Equivalence Partitioning:
- One input data class with all valid inputs. Pick a single value from range 1 to 1000 as a valid test case. If you select other values between 1 and 1000 then result is going to be same. So one test case for valid input data should be sufficient.
- Input data class with all values below lower limit. I.e. any value below 1, as a invalid input data test case.
- Input data with any value greater than 1000 to represent third invalid input class.
So using equivalence partitioning you have categorized all possible test cases into three classes and that can be (-10, 100 & 1010). Test cases with other values from any class should give you the same result.