Functional testing

For functional testing in manufacturing, see Functional Testing (Manufacturing).

Functional testing is a [[quality assurannd software engineering|publisher=ISO/IEC/IEEE 24765:2010(E)|year=2010|pages=vol., no., pp.1–418, 15 Dec. 2010}}</ref> Functional testing usually describes what the system does.

Since functional testing is a type of black-box testing, the software's functionality can be tested without knowing the internal workings of the software. This means that testers do not need to know programming languages or how the software has been implemented. This, in turn, could lead to reduced developer bias (or confirmation bias) in testing since the tester has not been involved in the software's development.

Functional testing does not imply that you are testing a function (method) of your module or class. Functional testing tests a slice of functionality of the whole system.

Functional testing differs from system testing in that functional testing "verifies a program by checking it against ... design document(s) or specification(s)", while system testing "validate[s] a program by checking it against the published user or system requirements."

Types

Functional testing has many types:

• Smoke testing
• Sanity testing
• Regression testing
• Usability testing

Six Steps

Functional testing typically involves six steps

1. The identification of functions that the software is expected to perform
2. The creation of input data based on the function's specifications
3. The determination of output based on the function's specifications
4. The execution of the test case
5. The comparison of actual and expected outputs
6. To check whether the application works as per the customer need.

See also

• Non-functional testing – Testing software for non-functional behavior
• Acceptance testing – Test to determine if the requirements of a specification or contract are met
• Regression testing – Checking whether changes to software have broken functionality that used to work
• System testing – Testing conducted on a complete software system
• Software testing – Checking software against a standard
• Integration testing – Type of software testing
• Unit testing – Validating the behavior of isolated source code
• Database testing – The testing of database software systems
• Security testing – The process of finding flaws in the security of information systems
• Load testing – Process of putting demand on a system and measuring its response
• Test automation – Use of special software to control test execution and analysis