What Is Equivalence Partitioning Technique ?

Equivalence Partitioning stands as a fundamental software testing technique, strategically dividing the input data of a software application into equivalent partitions. The primary objective is to ascertain that the software exhibits consistent behavior across various sets of input data, offering an efficient means to design test cases that cover a broad spectrum of scenarios. Here's a more detailed exploration of Equivalence Partitioning:

Definition: Equivalence Partitioning is a black-box testing technique that systematically categorizes the input domain of a software system into classes or groups of data, anticipating similar behavior within each class. The overarching concept is to test a representative from each class, minimizing redundancy, and ensuring thorough test coverage.

Steps in Equivalence Partitioning:

1. Identify Input Classes:

   • Understand the different types or ranges of inputs the system can accept.
   • Divide the input domain into classes or groups based on these types or ranges.

2. Select Representative Values:

   • Choose a representative value from each partition.
   • Testing a single value from each partition suffices; exhaustive testing is not necessary.

3. Test Boundary Values:

   • Pay special attention to the boundary values of each partition.
   • These boundary values, situated on the edges of partitions, are likely to exhibit different behavior.

4. Design Test Cases:

   • Develop test cases for each representative value, concentrating on the identified input classes.
   • Ensure coverage of both valid and invalid scenarios.

Example: Consider a system that accepts a numeric input denoting a person's age (e.g., 1 to 100). Equivalence Partitioning for this scenario might include:

• Partition 1: Age less than 1 (Invalid)
  • Represented by: -1, 0
• Partition 2: Valid Age Range (1 to 100)
  • Represented by: 5, 25, 50, 75, 100
• Partition 3: Age greater than 100 (Invalid)
  • Represented by: 101, 150

Advantages of Equivalence Partitioning:

1. Efficiency:
   • Provides robust test coverage with a reduced number of test cases.
2. Simplicity:
   • Simplifies the testing process by concentrating on representative values.
3. Error Detection:
   • Facilitates the identification of defects and errors linked to specific input classes.
4. Reusability:
   • Test cases can be reused when modifications are made to the system.

Limitations:

1. Assumption of Equality:
   • Assumes that all values within a partition are equivalent, which might not always hold true.
2. Overlooking Interactions:
   • Doesn't account for interactions between different inputs.
3. Complex Systems:
   • May become intricate when dealing with a large number of input classes.

In summary, Equivalence Partitioning emerges as a systematic approach for designing test cases that efficiently cover diverse input scenarios, establishing itself as an effective strategy in the realm of software testing.