The blockchain ecosystem, which has been all the rage in the tech world, can’t work without smart contracts. A “smart contract runs almost every blockchain-based app and service you see and use.” Smart contracts are used by dApps, NFTs, DeFi protocols for borrowing/lending or arbitrage trading, and a lot of other apps. Ethereum is the most popular platform for making smart contracts, and developers could get the most out of Ethereum by knowing how to test smart contracts on Ethereum. It’s important to remember that testing a smart contract is a must if you want to ensure it’s more secure. A lot of money has been put into dApps, DeFi protocols, and NFTs, all of which are built on top of smart contracts. Because of this, security is an important part of smart contracts.

The fact that smart contracts can’t be changed also shows how important it is to test them. There is no way to update them after you’ve sent them out into the world. So, all blockchain-based projects should thoroughly test smart contracts on Ethereum before using them. Let’s find out more about how to test the best ways to use smart contracts on Ethereum.

 

What Does Smart Contract Testing Mean?

The first thing you need to know about “How do you test an Ethereum smart contract?” answers is what “testing a smart contract” means. It refers to the process of doing a thorough analysis and review of smart contracts to check the quality of their source code as they are being built. The testing process makes it easier to find security holes and bugs. So, smart testing contracts could help make sure that smart contract logic or software errors happen less often. So, developers don’t have to worry about security breaches, which could lead to extra costs.

Depending on the benefits you want, you can use different tests for smart contracts. Manual testing and automated testing are the two main ways to test smart contracts on Ethereum. Here is a summary of both ways of testing.

 

Testing by hand

Manual testing, as the name suggests, requires that different steps be done by hand by a person. One of the most common ways that smart contracts are tested by hand is through code audits. During a code audit, developers or auditors look at every line of code to see if there are any problems. To manually test Ethereum smart contracts, you would need to know a lot about how they work. Manual testing also means that more work, time, and money will need to be spent. It’s also important to remember that mistakes can happen when testing is done by hand.

On the other hand, manual testing methods can help find bugs in smart contract logic that automated testing methods couldn’t find. Manual testing could also find flaws in smart contracts that aren’t in the code, like when they interact with components that aren’t on the blockchain.

 

Computerized Testing

The next answer to the question “How do you test an Ethereum smart contract?” would focus on automated testing. The process of testing a smart contract with automated tools that can make test scripts is called “automated testing.” The most important part of automated testing is software that can run multiple tests over and over to find bugs in smart contracts.

One of the biggest benefits of using automated tools to test smart contracts is that they save time and make better use of resources. Without having to do anything by hand, developers could work on improving the main part of the dApp. The most important thing is that, compared to manual testing, automated testing could help cover more parts of a smart contract. On top of that, automated testing tools let you set up test data in different ways, which makes it easier to compare actual results with what was expected.

I’ve always liked this diagram from @copyconstruct’s “Testing in Production, the safe way.”

We often collapse smart contract safety to “was it audited,” but automated testing, audits, monitoring, and bug bounties are all techniques on a safety spectrum. pic.twitter.com/tyGXxAPqjh

— horsefacts (@eth_call) March 17, 2023

Why Should Smart Contracts Be Tested?

One of the first things people want to know about testing Ethereum smart contracts is whether or not they need to be tested. The first reason to test smart contracts is that they are often used in situations where high-value assets are involved. Smart contracts are used in things like DeFi projects and tokens that can’t be traded. Even the smallest flaw in smart contracts could cause users to lose a lot of money in a way that can’t be fixed. Comprehensive testing mechanisms could make it easier to find mistakes in the logic of smart contracts and reduce security risks before they are used.

The next important reason to focus on testing smart contracts is that they can’t be changed. Once you’ve set up smart contracts on the Ethereum Virtual Machine, you can’t change them. After a smart contract has been put on the blockchain, there is no way to change its logic in order to fix security flaws.

Proxy patterns can be a good way to improve smart contracts, but they are hard to use. Not only would updates reduce immutability, but they would also need to involve complicated governance processes. Because of this, fewer code changes might be needed if smart contracts were thoroughly tested for bugs before being used.

Also, read – Top 5 Use Cases Of Ethereum Smart Contracts

What are the ways to test smart contracts automatically?

Functional testing and static/dynamic analysis are two of the most common ways to use automated tools to test Ethereum smart contracts. Let’s take a look at the methods used in these two ways of testing that are done automatically.

 

Checking how things work

One of the most common ways to test a smart contract automatically is to do functional testing. It focuses on ensuring that smart contracts work and guarantees that each function can work as expected. Functional testing also requires a full understanding of how smart contracts work in certain situations. You could test each function by running calculations with certain values and comparing the results to what you want to see. Functional testing could help test methods like unit, system, and integration testing cover more ground. Here is an overview of the different kinds of functional testing.

 

Tests on units

With functional testing, the first answer to “How do you test an Ethereum smart contract?” is unit testing. The unit testing method works by evaluating each part of a smart contract on its own. It’s important to remember that a unit test is simple, easy to use, and gives you a better idea of errors. Unit tests are a very important part of building smart contracts, especially when adding new logic to the smart contract code.

Unit testing could help you check how each function works and ensure it works how it’s supposed to. Developers of smart contracts can run unit tests by making simple statements called assertions. The assertions would list the things that smart contracts should do, and the unit tests would check to see if the smart contract does what it should.

 

Checking for integration

Integration testing is the next step in functional tests. As part of the method, smart contracts are tested by looking at all of their parts together. Integration testing is a good way to find errors that happen when different parts of a contract or contracts interact.

Integration tests are a good way to test Ethereum smart contracts with a complicated design with multiple functions. Integration testing is also a way for developers to find out which parts of a contract talk to other contracts. It’s also important to note that integration testing could make sure that things like dependency injection and inheritance work as they should.

 

System Testing

System testing is another way that has been shown to work well for testing how well a smart contract works. It is the last step in functional testing, and it involves judging how well smart contracts work as a whole. The main goal of system testing is to see how smart contracts work from beginning to end from a user’s point of view.

One good way to test a smart contract’s system is to deploy it in environments that look like production, such as tests or development networks. Rinkeby and Ropsten are two of the most popular testnets for Ethereum smart contracts. End users will be able to try out contracts and report problems related to their business logic on testnets or development networks. At the same time, they help check how well the smart contract works overall.