Code Refactoring and Its Role in the Software QA Process

Code refactoring is the process of restructuring existing code without changing its behavior. Its goal is to improve the design, structure or implementation of the software, while keeping its functionality. This article discusses how refactoring is integrated in software quality assurance (QA).

Author: Nataliia Syvynska, TestMatick,

Code refactoring is a special process that consists of editing and analyzing previously created code without changing its current function. This process aims to improve the overall efficiency of the code so that it is easy to use, contains as few edits as possible, and is easy to take apart.

Code Refactoring and Its Role in the Software QA Process

Main Techniques and Rules for Performing Refactoring

There are several popular and effective methods for performing code refactoring:

  • Red-Green-Refactoring;
  • Refactoring by abstraction;
  • Method of composition;
  • Simplifying method;
  • Preparatory code refactoring.

Let’s analyze each type in more detail.


This is a very popular technique that is in particular demand among software testing companies that follows an Agile approach for software development.

Its basic steps are:

  1. Define what needs to be done;
  2. Ensure the smooth execution of basic testing;
  3. Implement improvements (if necessary).

Refactoring by abstraction

This is ideal for a very high-volume refactoring process. With it, you can overcome the excessive amount of code by removing duplicate subclasses and collapsing the hierarchy.

This type of refactoring contains several execution methods, namely:

  • Pull-Up/Push-Down: “splits” one class into two, one of which will be tied to the superclass, and the second to the subclass.
  • Pull-Up: collects part of the code in a superclass and deals with code duplication.
  • Push Down: The method allows you to move code from a superclass to a subclass.

Composition method

During the software development stage, some software developers overwhelmed code with methods that are very difficult to change or reformat.

The composition method implies the analysis of the code for its unnecessary duplication. Such work is carried out using a variety of processes, among which are built-in refactoring and extraction.

Simplifying method

Don’t forget to remove old and unnecessary programming code, and simplify all the logic.

This is the simplifying method that not only consolidates the conditional expression but also allows you to structure the methods correctly.

Preparatory code refactoring

It is performed when the programmer sees the need for some code refactoring while adding new functions (parameters). In fact, this is a kind of entire software update rather than a separate refactoring process.

Influence of Code Refactoring on the Software QA Process 

The work of automated and manual QA engineers can be a good example to consider this issue.

After any refactoring, the main tasks of a manual tester are:

  • Thorough product testing from the position of its end user;
  • Performing regression testing;
  • Implementation of the first two points with consecutive frequency.

In an automated testing environment, things will be more complicated, since refactoring often leads to the situation when automated logic scripts could contain bugs:

  • Run all automated tests (change the location of the ID for the tested objects);
  • Performing other technical work that is required after the refactoring process (using Selenium or any other testing tool).

Also, we can make the following groups to see why software QA engineers should be familiar with code refactoring:

Unit testers/developers benefit from code refactoring as it involves upgrading old CSS classes and adding new program code. New unit tests appear while old ones are not executed.

Testers perform exhaustive and regression testing during code refactoring. This includes functional checks for all potential user groups. For example, in an online shop, testing involves the behavior of shop assistants and customers.

Automation test engineers may encounter failures in automated scenarios due to code refactoring. This can happen when object positions change or technical changes are not reflected in the build.

Test leads/QA leads require technical communication with developers, analysts, and clients. Understanding the technical aspects of program functionality is crucial for successful refactoring. Test leads/QA leads use this knowledge to create analytical business plans for clients and users.


The process of refactoring program code should be approached by the principle of the golden mean. You do not need to analyze the entire code at once but start working with the most important and complex parts, moving towards simple tasks. Timely and high-quality refactoring is the key to creating a reliable software product that will have good performance for its end users.