Variable values have certain types. In fact, you can cast a value of one type to the other. If you do it explicitly, it is type casting (also called explicit coercion). If it happens in the background when you are trying to perform an operation on types that do not match, it is called coercion (sometimes referred to […]
Today we test our React components further. It involves simulating component interactions and mocking the API calls. You will learn how to do both, so let’s go! Mocking A common thing is for our application to fetch some data from the API. A problem with it is that might fail for various reasons, such as […]
Hello! In the previous part of the tutorial, we’ve covered the very basics of testing React components with Enzyme. Today we will dig a bit deeper and learn how to test props, how (and why) use the mount function and what are the snapshot tests. Let’s go! Testing props In the previous article, we’ve tested […]
At the previous part of the tutorial, we’ve briefly covered the basics of unit testing. This time we will go further and start testing React with the Enzyme library. Thanks to the that, your application will be more reliable and it will be easier to avoid regression. Even though we will be using Jest here, Enzyme also works […]
Hello! Today we start another big series, which is about JavaScript testing. There are various different types of tests and we will start by explaining some of them. In the beginning, we will cover the basics of unit testing, which is testing individual parts of our application and checking if they are fit to use. To […]
In the first article of this Webpack 4 course series, we’ve covered imports and exports. This time we will dig deeper into dynamic imports because they deserve a separate article. We will explain what they are and how to use them. Let’s start! Webpack 4 course: what are dynamic imports? Back in the days, ECMAScript […]
In this part of our webpack 4 course, we will take the idea of optimization even further. We will learn what the tree shaking is and how to use it. You will find out what requirements you need to meet in order for the Webpack 4 tree shaking to work and how can it benefit […]
Today we will cover the development value of the mode property. It will automatically set the webpack configuration for you to make the development easier. Aside from that, we will also cover the wepback-dev-server and webpack-serve – Hot Module Replacement included. Let’s go! Webpack 4 course: a development server A one step forward to a better development experience […]
In this part of the Webpack 4 course, we will focus on increasing the experience of users of your application by making our output smaller. This will mean handling the code in a different way in the production environment. Today we will explain the built-in optimization in Webpack achieved by the mode parameter, so let’s go! […]
Hello! Today we introduce the concept of plugins. They differ from loaders in a way that they can perform a wider range of tasks. Basically, they do anything else, that loaders can’t do. While loaders are tied to a certain type of files, plugins can be more generic. This time we will learn what purpose […]
Today we continue our webpack 4 tutorial. After walking through the basic concepts of webpack, it is time to go deeper. This time we will cover something that is a great strength of webpack: loaders. First, we will learn how to use loaders that are available. This will include handling css, scss, image files and […]