Understanding the Differences Between Unit Tests and Test Automation

As software creation processes continue to become more complicated, development teams are taking a more all-encompassing approach that involves agile testing methodologies. Like agile software development, agile testing involves running test cases that assess the overall integrity of a solution, rather than simply ensuring that each part and piece are technically sound. Viewed as an analogy, agile testing methodologies ensure that software is a well-oiled machine, whereas a linear approach to testing just ensures that each of the gears is in good order. Herein lies the difference between unit tests and test automation.

Zooming in With Unit Testing

Unit testing is an effective way to organize tests by code. In other words, specific components of a larger product can be closely examined to ensure functionality. This can be useful in helping to catch tiny glitches that might not be so easy to identify later on in the process. This is because each and every line of code is viewed as a single unit unto itself, rather than a small part of something bigger. Thus, unit testing is very small and granular in scale, and can be extremely time consuming as a manual process.

Another downside of unit testing is that it is not a failsafe test management system. By design, unit tests are very isolated, and look for small, specific issues in coding. While this provides a detailed sweep for bugs, it also eliminates the collaborative, panoramic approach to software development and testing that DevOps culture has made so prevalent. Agile testing suddenly becomes a lot less agile and a lot more rigid. In the long term, this can leave the user experience looking and feeling somewhat shortchanged

Automation Integration Caters to Agile 

According to DZone contributor Ayende Rahien, too much focus on unit tests can ultimately defeat the purpose of a test management strategy.

"At the end, it boils down to the fact that I don't consider tests to be, by themselves, a value to the product." Rahien said. He explains that the main purpose of a test is to determine if something is serving its function. Unit tests can ensure that code is methodically scripted, which can prevent bugs, but its assessment of the overall solution is limited. The last thing an agile software developer wants is a test management strategy that is overly myopic. 

Automation integration can provide a more comprehensive assessment by running multiple test cases as each line of code is scripted, giving developers a more elaborate understanding of a project's overall integrity - and potential value to users - as it evolves. Furthermore, because testing is automated, the risk of human error is reduced, and cases that need to be run over and over again take significantly less time to execute. 

One option for developers is to automate unit tests. This can ensure that all written tests run when they need to. Other, more overarching tests can also be executed to help ensure that the product is performing well, and in a way that end users will find appealing, and represents a great method for ensuring reliability and fluid functionality.