What is a Test Harness in Software Testing?

Harness in a literal sense is a gear that is used to take control of something. In software testing, it is none different. In testing terms, It refers to a collection of software, test drivers, test data and other supporting tools that are constructed to test an application by executing it under different environments and analyzing its results. It uses test libraries to execute tests and generate a report.

A test harness in layman language is to make automation framework and use its constituent elements to take charge of the testing activity to get the best results.

What are the objectives of Test Harness?

• Automate the testing process.
• Helps in test case optimization by selecting specific tests to run
• Execute test suites of test cases.
• Organizes a run time environment
• Generate associated test reports.
• Analyzes test results.

What are the Features of Test Harness?

• Executes test suit in the framework
• Assists measure the code coverage at the code level.
• Enters test data to an application under test
• Captures the output from the software under test
• Offers flexibility and support for debugging
• Records test results

What are the benefits of Test Harness?

• With more effective automation, increases in productivity.
• Improved software quality.
• Automates the testing process.
• Supports debugging.
• Supports scheduling of tests.
• Good for complex conditions.
• Automated test reports generation.
• Records test results.
• Enhanced productivity.
• Enhance software quality.

Contexts where Test Harness is used
1. Test Harness in Test Automation
Test harness in automation testing refers to the software systems and the framework that includes test data, test scripts, test results and compares them and analyze the results.
For example, if you use any testing tool for functional testing, it organizes and manages all the test data, scripts, runs, and results. The test harness for it will be:

• The testing tool
• The scripts and
• The physical location where they are stored
• The Test sets
• Test data for the test scripts
• The test results and the comparative monitoring attributes

2. Test Harness in Integration Testing
Integration testing is testing whether the combined behavior of two or more integrated code is as expected or not.
In an Ideal scenario, Integration testing of two modules is possible when both of them are 100% ready, unit tested and good to go.
But, this everything can’t be perfect at all times. And we might land up in a situation where above conditions are not fulfilled. Hence we use  (stubs and drivers) to overcome this situation. A stub is a proxy piece of code that substitutes the missing piece of code.

What is the difference between Test automation framework and Test Harness?

Test Harness Tools
Though there are no specific tools, it includes tools like test management tools, automation testing tools, etc. Any similar test tool can be an element of the test harness.
Conclusion
Since now you know a lot about test Harness, do keep an account of this when you leverage for your automation testing. Be wise in your selection and usage of test harness; it can bring huge benefits to your test automation.