Statement Coverage

Introduction to Statement Coverage

Statement coverage is the broadly used code testing technique used in the software development process and it falls under the category of white-box testing.  This type of test execution process is the one that includes a series of testing on the statements in the code. It is used in creating the test scenarios that should incorporate each and every statement from the code to be subjected to the testing process at least once during the process. It is run through every line of the code, as it is important to identify every statement in the code in order to apply this technique.

How Statement Coverage Testing is Performed?

The Statement Coverage Testing is put into practice in the software development life cycle as a part of code validation, during the build and development phases. All the discrepancies and unnecessary codes found in the source code is addressed by the programmers and application developers right at the moment. Failing to do so might result in redundancy in the source code, unnecessary space occupation, obsolete code snippets, extra minutes/ seconds in the application run time, etc. When done correctly, this process plays a major role in increasing the overall functioning and performance of the software product. This form of code testing is a well-known step in the software application development process in terms of optimizing the functional flow. Missing to perform this procedure on the source code can result in the lack of efficiency and an increase in the execution time of the application.

• The first step in the Statement coverage testing process is performed by examining the complete functioning of the program, and to trace the statements in the programs of each module in the software. The functional parts of the statements can be characterized by matching the same with the requirements provided by the clients in the form of requirement specification documentation.
• The next step entails the course for collecting the statements through the source code and documents the same, and that includes this document to the project repository. So that this process can be carried out by the developer or the testing professionals, depending on the functional point involved in the code statements.
• The final step in the Statement Coverage testing is to verify all the statements listed in the previous step. This evaluation should include fact checks like comparing the functional features of the statements against the requirement provided, verifying the modularity of the application, the code should have only relevant content, code coverage validation accuracy, validation on optimization percentage, etc. This testing procedure is complete and confirmed as a ‘pass’ if the results from this test execution is equivalent with the expected result defined during the documentation stage, and this result set is supposed to be relative to the information provided by the client during the requirement gathering phase.

How to Calculate Statement Coverage?

The rationale realization of this Statement Coverage technique on the software application’s code is to confirm all the feasible utilities flow in through the application while it is put to use. Additionally, the course of action after the validation is employed on the application system is to prove that the performance is better, and is calculated using the below formula,

Statement Coverage (%) = (Number of statements executed as a part application’s code) / (Total number of statements in the application’s source code) * 100,

where the total number of statements represents the mentions from the requirement document, and the number of statements executed represents the statements present in the source code.

Examples to Implement of Statement Coverage

Below are the examples of Statement Coverage:

Example #1

Below pseudo-code for demonstrating the Statement Coverage validation.

Code:

Read X
Read Y
IF X*Y  > 500 THEN
Print “Product of X*Y is greater than 500”
ELSE
Print “Product of X*Y is lesser than 500”
ENDIF

Here, the Numbers X and Y are received as the input from the user. The next step is to validate if the resulting product is greater than or lesser than the number 500. The resulting value decides which statement will be executed. Hence the code can be considered as an optimized code snippet. Also, this improvises the performance and efficiency of the product resulting from the code.

Example #2

Consider the below code as an example for Statement Coverage.

Code:

{
input (int X, int Y)
{
Z = ((X + Y) / 200 )* 100
If (Z>50)
{
Print (PASS)
} else
{
Print (FAIL)
}
}
}

Here, the marks in the two subjects are assigned to the variables X & Y and is categorized as integer data types. The next step is to calculate the percentage, using the formula ‘((X + Y) / 200 )* 100’. The resulting value is assigned to another integer labeled as Z. The Z is then subjected to the if-else loop, where if the Z is greater than 50 the system prints ‘PASS’, and if the resulting value is less than 50 then ‘FAIL’ is printed. In terms of performance and optimization, the calculation needs to be done only once as we have used if-else statement and not a switch conditional loop statement.

Advantages and Disadvantages of Statement Coverage

Below are the advantages and disadvantages of Statement Coverage:

Advantages:

1. This process is applied on the source code units for increasing the performance of the application software.
2. This method aids in managing and maintaining the quality of the software application.
3. It facilitates in tying all the lose knots in the code, and cut off the disused parts of the source code that is overlooked.

Disadvantages:

1. As this method of coverage testing is not included in the traditional software development life cycle, it is not considered during the planning phase.
2. Since it is not usually considered in the planning phase, it brings surprise costs and efforts when brought into picture in a later point of time.

Conclusion

Statement Coverage Testing is an imperative testing method when it comes to the code validation process. It provides a healthier view on the depth of the code and the operations covered in the source code of the software application program. This step is typically performed by the development team, by using a testing tool, in most cases.

Recommended Articles

This is a guide to Statement Coverage. Here we discuss the Introduction and how to Calculate Statement Coverage along with advantages and disadvantages. You can also go through our suggested articles to learn more –

1. Software Design Principles
2. Branch Coverage
3. Decision Coverage
4. Test Coverage Tools