CHAPTER-7

TESTING

Tesing Can Be Defined As:

Testing is the process of executing a program with the intention of finding Errors.(or) Testing is the process of verifying an application to check if the application is behaving as per the Requirements(or)Testing is the process of executing test cases on the application to differentiate between the Expected and Actual results(or)Testing is the process of verifying customer needs with respect to the designed application(or)Testing is the process of finding errors, faults, defects, bugs, issues in the application.

Testing is the process of requirements analysis, test cases designing, test cases executions, bug reporting, test status updates, customer interactions, application maintenance(or)Testing is the process of V & V (Verification and Validation) .

Reasons for Testing:

To find defects.

1.To ensure that application meets customer expectations / requirements.

2.To reduce cost of quality by delivering defect free product on time, within the budget.

3.To achieve customer satisfaction.

4.To continuously improve testing process in the SDLC.

5.To reduce risk of software failure. To determine the state of software

.6.To deliver a quality and bug free application to customer

7.To retain the company name and fame

.8.If there is no testing, then there is no quality products/projects/applications.

Few other reasons:

1.Developer thinks in the point of code, structures, loops, statements, code integrations and so on

2. There should be someone else who could think in the point of functional behavior.

3.There should be someone who could think in the view of customers / end users.

4.And thus, tester comes into picture and testing is needed for sure.

Testing begins right from the requirements analysis.

To check:

If the requirements are clear and If the requirements are understandable and If the requirements are testable and If the requirements are transformable into software/program .

Requirements for Testing:

1.clients / Customers (Grey Box Testing > Code , Functional , UAT)

2.Testers (Black Box Testing > Smoke , Functional, Integration , System , Regression Testing)

3.Users (Functional , UI Testing)

4.Developers (White Box testing > Unit Testing , Integration Testing)

5.Tester is the right MAN of all to validate Application.

6.Testing also Need:

7.Requirements/ Specifications / wire frames

8.Good understanding of BRS/SRS/ wire frames

9.QATP (Test Plan), QATC (Test cases)

10.Test Set up (Environment, Software & Tools)

11.Resources (Machines, Testers, Lab).

Types of Testing :

Manual Testing:

1.Sanity Testing

2.Functional Testing

3.Integration Testing

4.System Testing

5.UI Testing

6.Regression Testing

7.Bug Verification / Bug Tracking

8.Compatibility Testing

9.UAT ( Alpha and Beta)

Automation Testing:

1.Sanity Testing

2.Functional Testing

3.Regression Testing

4.Load Testing

5.Performance Testing

6.Stress Testing

Reason For Bugs In Softwares:

1.Poor Requirements (Unclear Requirements)

2.Programming errors

3.Software complexity

4.Changes in Requirements

5.Time pressure

6.Inefficient Dev (Poorly coded modules)

7.Poor Management

8.Poor Documentation

9.Poor Quality Assurance

The Flow Of Testing Process Is:

Various Testing Strategies Are:

Unit Testing:

Unit testing focuses on the building blocks of the software system, that is, objects and subsystems. There are three motivations behind focusing on components. First, unit testing reduces the complexity of overall test activities, allowing us to focus on smaller units of the system.

Second, unit testing makes it easier to pinpoint and correct faults, given that few components are involved in the test. Third, unit testing allows parallelism in the testing activities that is each component can be tested independently of the others..

Test case idInputExpected Behavior

1Valid username, Valid email, valid PINPass

2Invalid username, Valid email, valid PINFail

3Valid username, Invalid email, valid PINFail

4Valid username, Valid email, Invalid PINFail

Integration Testing:

Integration testing detects faults that have not been detected during unit testing by focusing onsmall groups of components. Two or more components are integrated and tested, and when no new faults are revealed, additional components are added to the group.

This procedure allows the testing of increasingly more complex parts of the system while keeping the location of potential faults relatively small.

System Testing:

Unit and integration testing focus on finding faults in individual components and the interfaces between the components .Once components have been integrated, system testing ensures that the complete system compiles with the functional and non-functional requirements.

White Box Testing:

White Box testing is a process of uncovering errors in the internal logic of the application. It uncovers the errors like, Syntax errors and logical errors.

Black Box Testing:

Black Box testing focus on testing external functionality of the software. It enables the testers to derive a set of inputs that will fully exercise all the functions of software. It uncovers the errors like, missing functions, interface errors, errors in database access, initialization and termination errors.

Test Criteria and Test Cases:

A realistic goal for testing is to select a set of test cases that is close to ideal. An ideal test case set is the one that succeeds only if there are no errors in the program. We define a criterion that we believe should be satisfied during testing. The criterion then becomes the basis for test case selection and a set of test cases is selected that satisfy that criterion.

For example, the criterion can be that all the statements in the program should be executed at least once. For this test criterion, we have to select a set of test cases that will ensure that each statement of the program is executed by at least one of the test cases.

There are two aspects of test case selection: specifying a test criterion for evaluation a set of test cases, and a procedure for generating a set of test cases that satisfy the given criterion. A test criterion is to be specified. And based on the criterion, we have to generate all the possible test cases.

There are two fundamental properties for a testing criterion: reliability and validity. A criterion is reliable if all the sets of test cases that satisfy the criterion detect the same errors. A criterion is valid if for any error in the program, there is some set satisfying the criterion that will reveal the error. As getting an ideal test criterion is not generally possible, other more practical properties of test criteria have been proposed.

The following are the some of the test criteria.

Coverage Criteria:

Coverage criteria are based on the number of statements, branches or paths that are exercised by the test cases.

Statement Coverage Criteria:

Perhaps the simplest and weakest coverage criterion is statement coverage, which requires that each statement of the program be executed at least once. This coverage criterion is not very strong and can leave the errors undetected.

Branch Coverage Criteria:

This requires that each branch in a program be traversed at least once during testing. In other words, the branch coverage requires that each decision in the program be evaluated to true and false values at least once during testing.

Path Coverage Criteria:

This requires that each logical path in the program be tested during testing. A logical path is the sequence of branches that are executed when the program is executed from the start to the end.