What is loop testing in software testing?

Overview

Software testing is an essential part of the Software Development Life Cycle (SDLC) to ensure the quality of a software product. Out of the several software testing techniques employed, we will discuss the loop testing technique.

Definition

The loop testing technique is used to validate all loops in a program. The validation of a loop entails the following:

• Fix infinite loops.
• Gauge loop performance.
• Identify loop initialization problems.
• Determine uninitialized variables.

Types of loop testing

Simple loop testing

In simple loop testing, a simple loop control structure (either for, while, or do-while) is tested to ensure that it terminates at some point.

Example

for (initialization; condition; increment) {
  statement(s);
}

Nested loop testing

Nested loop testing is applied when at least one loop is nested inside another. We make sure that the outermost loop terminates by varying the iterations and conditions in the inner loops.

Example

do {
  while(condition2) {
    statement(s);
  }
} while(condition1);

Concatenated loop testing

Concatenated loop testing is applied when loops are in series and their conditions are dependent upon the same variable, initialized for the first loop.

Example

do {
  statement(s);
} while(condition1);
while (condition2) {
  statement(s);
}

Unstructured loop testing

Unstructured loop testing is applied on a combination of nested and concatenated loops.

Example

do {
  while(condition2) {}
  while(condition3) {}
} while(condition1);

Advantages of loop testing

• Gets rid of the infinite loop problem.
• Ensures that all variables used inside the loop are initialized.
• Problems inside the loops are identified and fixed.

Disadvantages of loop testing

• Only useful for low-level software bug detection.
• In high-level software, bug detection via loop testing is not useful.