Unit Testing vs Functional Testing: A Comparative Guide

  • Unit testing enables developers to not only refine the code but also ensure the module works as intended and as productively as possible.
  • This type of testing also allows teams to test only specific parts of the software without needing to wait for the rest of the parts and project to be completed.
  • This type of testing is highly conducive to ensuring the development team is successfully able to fulfill not only the client’s requirements and expectations but also those of the clients they eventually intend to serve.
  • Functional testing empowers the team charged with software development to incorporate user perspective while developing test scenarios that exemplify real-world used scenarios.
  • Such testing is also used by developers to scale up the system’s actual usage via improvement of the software product’s quality.
  1. Coverage: With unit testing, developers can achieve high code coverage which, in turn, supports the conclusion that the project has been properly developed and maintained. Whereas with functional testing, test coverage seeks to sync the project’s requirements and the test cases.
  2. Purpose: Developers use unit testing to establish a sturdy codebase without necessitating humongous investments. Such tests also supply documentation for high-level testing, such as functional testing, integration testing, etc., further on in the development process. The key goal of functional testing is to analyze all the functionalities of the given system. This type of testing involves close evaluation of the application, the networking infrastructure, the hardware, etc.
  3. When?: Some are inclined to believe that unit tests can be used in place of functional testing: this is not true. Both types of testing serve different purposes: unit tests should ideally start being written right along with the start of the development project since it allows developers to not only refactor the code but also determine if any part of the code has been inadvertently broken. Unit testing is followed by functional testing which should be started when two modules in the code end up engaging and interacting with each other.



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Ryan Williamson

Ryan Williamson

A professional and security-oriented programmer having more than 6 years of experience in designing, implementing, testing and supporting mobile apps developed.