Design Of Test Cases

A test case in software engineering is a collection of circumstances or variants or variables below which a tester will establish if a demand or requirement or use case upon a software or an application is fractionally or completely gratified. It may take several test cases to ascertain that a demand or requirement is fully pleased.
Test cases are regularly applied to as a test scripts. Written test cases are commonly gathered into test suites.

There are mainly two types of requirement based test cases mentioned as below :-
1- Formal Requirement Based Test Cases
2- Informal Requirement Based Test Cases

FORMAL REQUIREMENT-BASED TEST CASES:- In order to completely test that all the demands or requirements of a product or an application are encountered, there must be at any rate, on test case for every demand or requirement except a requirement has sub-requirements. In that condition, every sub-requirement must have at most one test case. This is often done by using a traceability matrix. There should be two test cases at any rate for each demand or requirement . One of them should be execute positive testing of demand or requirement and another should be executed as negative testing. Written Test cases should contain a variety of the work flow or the functionally to be tested, and the provision needed to assure that the test can be performed or can be conducted.

In a formal requirement based test cases have generally, known input and expected output of the written test cases, which is normally worked out ahead that test is executed.The recognized input should test a prerequisite and the prospective or expected output should test a post condition.

INFORMAL REQUIREMENT-BASED TEST CASES:- For the software or application or product beyond formal demands or requirements, test cases can be composed based on the approved ordinary actions of programs of a equivalent class.

FORMAT FOR THE TEST CASE:- Test cases generally have the following elements:-

1- Test case Id
2- Objective
3- Precondition
4- Steps to execute the test case
5- Actual Result
6- Expected Result
7- Status