These days, it's simple to become confused by all the JavaScript testing options available. For that reason, at TestQuality we felt it necessary to compile this testing tutorial post for JavaScript programmers. Here, you'll learn how to choose the optimal resources for doing unit and end-to-end tests in JavaScript.

JavaScript is single-threaded, but did you know that you can get multithreading with web workers? In this article, Badmus Kola explains how to use web workers to perform operations in parallel.

What a time to be alive! The information age we are currently in has given us more data and choices about, well, everything. But let’s be honest, do any of us actually feel like we’re more informed than we were? Because all this information comes with more choices. Expanded choice is actually an “explosion of choice” – in other words, if the world were a restaurant, the menu is so long you spend more time choosing your order than actually eating it.

Checking data types for variables is vital in any programming language to ensure a smooth and error-free development process. However, this becomes even more essential for accuracy when it comes to dynamically typed languages such as Javascript. In Javascript, one variable can hold multiple value types within the same file as shown below: To achieve this, one of the most commonly used operators is typeof.

JavaScript (JS) is the most popular programming language and is ranked as one of the TOP 5 programming languages in the world. TypeScript is JavaScript with type syntax and is a strongly typed programming language based on JS that provides better tooling at any size. But, internally, it’s again JavaScript. Today almost everyone uses JavaScript for front-end web development, and frameworks such as React, Vue, and Angular made JavaScript even more popular.

The JavaScript error TypeError: null is not an object occurs when a property is accessed or a method is called on a null value. This specific error message is shown only on Safari. Other browsers display a different message for this error. Error message: Error Type.

The TypeError: Cannot read property 'length' of undefined is one of the most common type errors in JavaScript. It occurs when the length property is read on an undefined variable. Error message: Error Type.

The Javascript ReferenceError occurs when referencing a variable that does not exist or has not yet been initialized in the current scope. The ReferenceError: event is not defined usually occurs while using an event handler if the event parameter is either not declared or declared incorrectly. For example, if on an onclick event, the handler does not declare the event parameter, this error is thrown.

In Loadero we always look for ways to improve our product and make it more robust, secure, and maintainable. As we add more features to our product, the complexity of our code base increases and it makes it more difficult to add or refactor the code without introducing regressions of the functionality. Since our frontend was written in plain Javascript and React, there was no way to ensure type safety of passed data between components and functions.