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Cucumber.js for BDD: An Introductory Tutorial With Examples

This post was written for the Testim blog. You can read the original here. Cucumber.js and BDD aren’t new kids on the block. But they’re still fairly unfamiliar for many developers. That’s unfortunate, because the two can be very powerful tools for both the business people and developers. Let’s have a short look at what BDD is, and […]

Get Started Quickly and Easily Testing with Mocha and Chai

This post was written for the Testim blog. You can read the original here. Looking to test your JavaScript and/or TypeScript code? Then you could do worse than go for testing with Mocha and Chai. These two libraries are among the most popular tools that developers use to write tests for JavaScript or TypeScript code. But if you’re […]

QUnit Tutorial: Start Unit Testing and Measuring Code Coverage

This post was written for the Testim blog. You can read the original here. There are many libraries available to write unit tests for your JavaScript code. One popular option is QUnit. Let’s look at how you can get started with QUnit. But let’s not stop there. Measuring code coverage of your tests is a […]

Escaping the Catch-22 of Anti-Test Arguments

There’s a Catch-22 hidden in the arguments that many people use to rationalize not writing tests. The Catch A Catch-22 is a situation that you can’t escape out of due to contradictory rules or limitations. In case of automated tests for software, the arguments often go like this. At the start of the project, both […]

How to Get Away with Unit Testing Legacy Code

A while ago, I did a webinar for TypeMock about unit testing legacy code. It’s about why we want to unit test legacy code, the advantages and disadvantages, and it includes some minor live coding using TypeMock’s Isolator tool. You can watch it here: I hope you like it. Let me know what you think!

Property-Based Testing with TypeScript

I’ve written about Property-Based Testing for .NET previously. It’s a way of writing unit tests with random (but constrained) inputs. This means your tests are run multiple times with different inputs and your code is tested more thoroughly. You might even find bugs you didn’t know were there. As I’m working quite a bit with […]

Are Unit Tests Not Necessary in Serverless Development?

If you’ve been following this blog for some time, you know I develop software mostly using test-driven development AKA TDD. But while this mostly means unit tests, it shouldn’t be limited to only unit tests. At one of my current clients, we use AWS Lambda functions written in TypeScript. These are (usually) relatively small blocks […]

Unit Testing Best Practices: 7 Ways to Improve Your Tests

This post was written for the NCrunch blog. You can find the original here. Unit tests help developers write better code and provide a faster way of getting feedback compared to testing manually. But unit tests are also another piece of code that must be maintained and taken care of. Unit tests can become a […]

Finding Unknown Bugs with Property-Based Testing

This post was written for the NCrunch blog. You can find the original here. There are many ways of testing your application or library. The test pyramid provides a good starting point to the most common types of tests—unit tests, integration tests, end-to-end tests, and manual tests. But there are other types of tests, like […]

Getting Started With TDD in Your Existing Project

This post was written for the NCrunch blog. You can find the original here. Test-driven development is a technique to drive the development of your project. TDD enables you to verify your code, it provides confidence for refactoring, and it enables a cleaner architecture. But what if you already have an existing codebase that wasn’t developed with […]