What is test coverage and its advantages and disadvantages?
Test coverage or Code coverage is a very useful tool which is used to test untested parts of code. Test coverage is a measure which is used to describe the degree to which a source code of program is tested by a particular test suite.
A program with more test coverage has lower chances of containing bugs and a program with lower test coverage has higher chances of containing more bugs.
Types of Coverage Testing:-
1) Statement Coverage:- In this type of coverage, test case is executed in such a way that every statement of code is executed at least once.
2) Branch Coverage or Decision Coverage:- It requires enough test cases so that each condition in a decision takes on all possible outcomes at least once, and each point of entry to a program is invoked at least once.That is each branch is taken in each way, True and False. It helps in validating each branch of code.
3) Path Coverage:-Path coverage ensures covering of all possible paths from start to end
Benefits of test coverage:-
1) It creates additional test cases to increase test cases
2) It helps in finding areas of a program which are not tested by set of test cases
3) It helps in determining quantitative measure of code coverage, which indirectly measure the quality of a product
Disadvantages of test coverage:-
1)Code coverage measures coverage of what has been written i.e. the code itself; it cannot say anything about the software that has not been written.