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DApps and smart contracts are increasingly adopted worldwide, and not just in the cryptocurrency sphere; they are becoming a vital part of doing business in the twenty-first century. However, with their enhanced usage comes a number of challenges, like their efficiency, quality, balanced costs, and safety, to name a few. One of the solutions provided to address this is testing, carried out by designated quality assurance specialists.

DApps and Smart Contract Testing Challenges

DApps and smart contracts usually require the same testing methods as any other software products. Often, though, they call for more frequent and precise tests: the technologies are still nascent, and their reliability is a matter of engineering talent behind them.

Just some of the associated challenges include:

• Irreversibility and immutability of blockchain transactions, meaning that even one code error would require developing a new smart contract from scratch.
• Absence of explicit instructions, well-ordered steps, and instructions on DApp development as seen in more established technologies.

Testing a Smart Contract

Testing is a safe way to ensure the accuracy, suitability, and effectiveness of smart contracts. For this, QA engineers run them in the testing environment before sending it to production.

After smart contract terms are set and sent to the production environment, they become unchangeable. This necessitates the need to ensure their integrity and workability before submission even though smart contracts can be amended at the code level, if necessary.

QA engineers can test the following smart contract features:

• Digital signatures
• Code structure and its suitability for execution terms
• Availability of resources for smart contract execution
• Error messages and notification systems

To test how accurate and failure-proof transactions are, QA engineers will check every aspect, including the date, parties of the contract, its execution time, hash validation, and fund transfer processes.

For this, they typically run the following testing types:

• Unit testing: this is conducted to examine individual functions of a smart contract, defining if it’s fit for use.
• Regression testing: this is done when a smart contract code gets modified, so QA engineers re-run unit tests written earlier to make sure that the smart contract remains error-free and operates smoothly.
• Integration testing: this is necessary to define that all the smart contract modules, including those facing other systems, are well-combined and run without errors.
• Compliance testing: this helps to verify that a smart contract meets all the regulatory requirements, especially where it concerns user data.

The list of testing methods isn’t limited by the test types mentioned above. QA engineers can recourse to both completely manual testing to thoroughly test each part of a smart contract and automated testing to ensure full test coverage. According to software testing experts, the latter also comes in handy provided the exorbitant number of nodes and their possible variations.

To ensure stable and predictable performance of smart contracts, QA engineers need to work in sync with the developers to foresee all the possible contract outcomes in advance.

DApp Testing

DApps, just like other applications, consist of backend and frontend layers. While their frontend shows little difference when compared to traditional apps and can be written using any programming language, the backend has a different structure, relying on blockchain technology. To this end, a user may not even realize that he or she is using a DApp.

DApp testing won’t differ much from traditional app testing in its methodologies. QA engineers will use functional testing to evaluate that a DApp complies with its functional specifications, and non-functional testing to check a DApp’s performance, usability, reliability, security, and scalability, among other aspects.

The Future of Decentralized Tech and Testing

Decentralized applications and smart contracts are proclaimed to be the future of information technologies. Even though those are still in their infancy, many businesses have already turned their eyes to them. Some notable examples include Fiction Riot’s platform that uses blockchain technology to pay royalties for video streaming and MetaXchain with their adChain product that allows for the building of dApps for fair digital advertising.

Though cutting-edge, DApps and smart contracts represent complex systems, requiring high precision and specialized engineering knowledge. Due to their complexity, the systems call for thorough and detailed testing to minimize the number of errors and make sure that this sophisticated technology works well.

There are many vital testing options open to companies developing decentralized solutions. That said, testing needs will be different for each project. Accordingly, the solutions used need to be appropriate to the software product and its requirements, be it a DApp or a smart contract.

In all cases, software testing engineers are the ones to evaluate and advise on the methods to be employed and aid companies in streamlining the development process by avoiding unnecessary steps.