What is Test Harness? (Examples)

Test Harness in Software Testing

Test Harness in Software Testing is a collection of stubs, drivers and other supporting tools required to automate test execution. Test harness executes tests by using a test library and generates test reports. Test harness contains all the information needed to compile and run a test like test cases, target deployment port(TDP), source file under test, stubs, etc.

Why use Test Harness?

Automate the testing process
Execute test suites of test cases
Generate associated test reports
Support for debugging
To record the test results for each one of the tests
Helps the developers to measure code coverage at a code level
Increase the productivity of the system through automation
Enhance the quality of software components and application
To handle the complex condition that testers are finding difficult to simulate

There are two contexts where Test Harness is used

Automation testing: It contains the test scripts, parameters necessary to run these scripts and gather results to analyze it
Integration testing: It is used to put together two units of code or module that interact with each other to check whether or not the combined behavior is as expected or not

Test Harness Tools

Junit: Tool used while using Java
Nunit: Tool used for using .Net framework

Test Harness Vs Test Framework

Test Harness	Test Automation Framework
A test harness is composed of drivers and stubs, which are small dummy programs that interact with the software under test	It is a set of processes, procedures, abstract concept and an environment in which automated tests are designed and implemented
You can not “Record & Playback” script in Test Harness	A tester can manually “Record & Playback” script in this framework
Test harness contains all the information needed to compile and run a test like test cases, target deployment port(TDP), source file under test, stubs, etc.	Test automation framework contains information like test library, testing tools, automated testing practices, a testing platform, etc.
A test harness is categorized into Automation Testing Integration Testing	Automation framework examples Data-driven testing Keyword driven testing Modularity driven testing Hybrid testing Model-based testing Code driven testing Behavior-driven testing