Software Testing with ABAP Unit

Target Audience
Motivation
Challenges That Affect the Use of ABAP Unit
Framework conditions for the use of ABAP Unit
The role of the DSAG ABAP guide in implementing your test strategy

When software is developed, it must be thoroughly tested during development and before it goes live. There are numerous and diverse methods and techniques for testing software. Testing is a time-consuming process, and if software is not tested carefully and comprehensively, this can lead, at best, to minor glitches and, at worst, to massive impacts affecting productive business operations. This can sometimes result in high costs for operating and further developing SAP systems.

Efficient and effective testing must take place as early as possible in the software development process in order to identify errors and problems as early as possible. With ABAP Unit, testing is integrated into the early phase of software development. In this chapter, we discuss why the use of ABAP Unit is necessary and beneficial, what challenges arise, and what conditions must be in place to use ABAP Unit tests effectively.

In addition, you will find a few tips on other testing tools and methods, but these will only be discussed briefly.
When the term unit tests is used in the following, it refers to ABAP Unit tests using the ABAP Unit framework. The term “ABAP” here refers solely to the specific features of unit tests within the ABAP Unit framework.

Definition of Unit Test
Unit tests often mean different definitions of tests.
When we write about unit tests here, these are programmed tests with the ABAP Unit Framework that can be executed automatically.
Manual execution of individual code units, e.g. using SE37 / SE24 / Reports, is not testing, but rather trying out functionalities.

Target Audience

In this chapter, we aim to provide decision-makers and managers with recommendations and insights on why ABAP unit tests are important for today’s modern ABAP programming and what benefits you can expect from this investment.
However, this guide is also intended to help developers, development managers, and those in similar roles make effective use of ABAP unit testing or, if it is not yet widely used, to make it easier to get started.
Perhaps this guide will also help motivate both developers and decision-makers to make extensive use of ABAP unit tests in the development process and to create the necessary conditions for doing so.

Motivation

Time is a critical factor in SAP projects. And there is usually significant time pressure when it comes to developing SAP applications and customizations. Creating ABAP unit tests and implementing the necessary technical measures requires time and expertise. This creates a tension, as it appears at first glance to involve conflicting goals. The software is to be developed quickly and within the project schedule. However, it must also meet all requirements and be robust and fault-tolerant—in other words, of high quality.

Co-founder of the Agile Manifesto and author of several books on software development, Robert C. Martin said:
“The only way to go fast is, to go well.”

Why should you invest time and effort in creating unit tests? Applied to the ABAP context, this statement means that if you want to be fast, you have to plan well.
Developers experienced with ABAP Unit know that creating software covered by ABAP Unit tests not only results in higher quality but also brings efficiency and speed advantages.
We would like to highlight these benefits at the beginning of this chapter and will then discuss ABAP Unit testing techniques and the necessary measures and procedures.

Advantages that arise from the use of unit tests:

The development of software supported by unit tests involves a clear structure that follows object-oriented design principles, due to the measures required to ensure testability.
Software that includes ABAP unit tests has a better structure and separation of concerns (business logic and technical coding) due to architectural requirements such as the separation of concerns. This makes the software more flexible and adaptable.
The development process includes a safety net that developers can use when further developing the software.
Errors are detected on the development system during development; this saves effort in integration and user testing.
The required creation of test cases and programmatic test data generation allows ambiguities in the requirements specification to be identified at an early stage of development.
Test coverage provided by unit tests enables continuous improvement and refactoring of the software, which prevents the accumulation of technical debt.
Knowledge sharing within the team: Unit tests document functionalities, making it easier for other team members to familiarize themselves with the code and adapt it, since unit tests represent a programmed specification of behavior and are also executable.
As soon as an application in production needs to be extended or modified, the benefits of ABAP unit tests become apparent, since testing can be performed using the tests already during development. Errors can be detected at the earliest possible stage. Thanks to the tests, test data and technical specifications are already available, which simplify the modification or extension of the code.

As a result of the points mentioned above, the testing effort required for the application is significantly reduced by the business department. Modifications and enhancements to the applications are significantly simplified by the implementation of unit tests and, above all, made safer, since new errors are already detected by the existing unit tests during development and thus do not occur in the user tests on the test system. These are primarily structural errors or oversights, which are inevitable.

In addition to the general benefits, which have a positive impact on effort and organization, the use of unit tests also offers advantages for developers, who must first invest time and energy in creating unit tests and may have to overcome resistance as a result.

Benefits for the developer:

The need to program test data gives developers valuable insight into the data to be processed, providing them with useful information about the application being developed that helps them better understand and implement the requirements.
To implement tests, a solid structure must be established from the ground up. This prevents the creation of code that mixes different concerns and makes later modifications difficult.
Once the first tests are written, the application’s components can be executed and debugged on the development system, thereby providing valuable insights into runtime behavior early on and avoiding misconceptions that would otherwise require significant effort to fix.
The initial additional effort is offset by later efficiency gains. Because developers deliver higher-quality software validated by unit tests, faster-functioning software can be made available on the test systems, and fewer errors occur in later test phases, the overall effort is reduced; there are fewer test cycles, and this ultimately increases satisfaction on both the development and user sides.

Challenges That Affect the Use of ABAP Unit

Lack of Knowledge and Insufficient Qualifications

Even in 2025, companies continue to face the challenge that a significant proportion of ABAP developers lack the knowledge and experience needed to create automated tests efficiently with ABAP Unit. Doing so requires knowledge of modern object-oriented programming, separation of concerns, structuring software into testable units, and unit-testing methodologies. Training is one contributing factor, as application development also demands a strong understanding of business processes. Consequently, many ABAP developers possess excellent knowledge of procedural techniques and the implementation of reports and traditional applications. However, there is still significant room for improvement in modern ABAP techniques and methods that have long been standard in other programming languages.

Lack of Experience as a Barrier to Implementation

“No tests without testing”

Techniques and methods that a developer does not master, does not use regularly, and is not required to use will not be employed when under time pressure. Under such conditions, it will be difficult to implement unit testing across the board. The benefits mentioned above will not be realized. This leads to high testing costs, errors in the production system, and difficult and time-consuming software modifications.

Time Pressure and the Definition of Done

SAP projects are often characterized by tight deadlines and high pressure to succeed. Developers have limited time to implement requirements and are expected to deliver testable versions of the application at an early stage. Whether an artifact is considered delivered usually depends on successful acceptance of the required functionality during user testing. Unit tests may be covered in manuals and development guidelines, but are often not part of the acceptance process. Their absence may therefore be accepted because the functionality can be put into production without them. The resulting technical debt is not immediately apparent and is accepted either consciously or unconsciously.

Framework conditions for the use of ABAP Unit

For ABAP Unit tests to become established in application development and be used effectively, decision-makers and those responsible for operating SAP software must change their mindset.
Knowledge of ABAP Unit must become a required and verified skill for ABAP developers. Creating ABAP Unit tests must be included in the definition of done and the scope of software delivery, rather than being treated as an optional task.

On the one hand, the use of ABAP Unit must be defined and prescribed in the development guidelines and manuals in order to create a commitment. As described above, the formal definition alone will not result in the widespread use of unit tests. In order to achieve this, in addition to formal requirements, framework conditions must also be created that address both the challenges described above and the challenges in the modern ABAP development environment and enable the development teams to integrate ABAP unit tests into everyday developer life.
A detailed description of the necessary framework conditions and best practices in practice can be found in chapter Organization: team organization

The role of the DSAG ABAP guide in implementing your test strategy

ABAP Unit requires the consideration of numerous aspects by the development organization, the responsible persons and the developers. In order to be able to use the ABAP Unit sensibly and effectively, the developer requires a good knowledge of software development and modern programming in ABAP and a mastery of object orientation.
On the organization’s side, prerequisites must be created in both the development process and the framework conditions that support and promote the creation of unit tests. This guide covers all of these aspects and provides knowledge on the technical side. This can help you to derive the measures in your company and provide motivation and initial help for developers to immerse themselves in the world of ABAP unit tests.

In the following section, the technical basics of ABAP unit tests are explained, test and development techniques are presented and advanced techniques are also discussed so that the explanations create a good understanding and thus lay the foundation for unit tests to become part of the software development process.