UI Testing with React Componet
Backend testing is quite easy but it is the opposite when it comes to front-end code testing that is difficult.thoughts on the article ReactJS Components Make UI Testing Easy
Backend testing is quite easy but it is the opposite when it comes to front-end code testing that is difficult.ReactJS is popular among web developers and what runs your test cases is the continuous integration service.ReactJS uses JSX that has a unique HTML syntax rendering specific components. Test-Driven Development (TDD) seems to be a weird choice but what makes backend testing easy is a predictable environment and continuous integration support with multiple test runners. With the evolution of backends adopting database servers and implementation of frontend MVC (Model-View-Controller). We test the complex codes on web browsers and the web applications are not tested. The UI components in the frontend code make the testing process complicated.
The checklist of ReactJS unit testing points are as follows:
- Well structured code snippets or isolated modules called UI components
- Utilize Mocha or Jasmine testing methods for running functions
- Use Test runners
Front-end testing is something beyond mere unit testing:
Testing designed to check fundamentals such as input logic validity checks, data transformations, or any silo operation checks. But the golden rule of unit testing is data needs to be validated and not manipulated at any cost. It functions on the basics of insight management that is getting the right views at the right time. Front-end testing is all about user experiences. We test user events and the response to those events.
Automation of ReactJS component testing:
Once the web developer has nailed the art to write components in ReactJs language then frontend testing seems to be a cakewalk.
Unit testing with ReactJS:
Components or reusable code snippets is what ReactJS coding is all about. ReactJS components are nothing but chunks of HTML code snippets built using functional programming principles. Talking about test user interactions in ReactJS we have user events and we also have function callbacks at checkpoints. Virtual DOM is an integral part of ReactJS that helps web developers with rendering the components into JS variables.
Jest for ReactJS application testing:
Built on Jasmine using its syntax and recommended by ReactJS documentation Jest is used for testing ReactJS components. However, using Jest for ReactJS application testing web developers would have a prior notion that it is a tedious process but it is not true. Enlisted are the steps involved when using Jest for ReactJS application testing.
- Execute the command “npx create-react-app my-app” for creating a web application based on ReactJS.You can also use a node package executor called npx that has npm embedded within
- Open the project after the command is executed successfully in a code editor
- Inside the code editor execute the command npm start
- Once the project is executed and compiled try opening a new web browser
- With the help of “npx command” care should be taken that Jest related all relevant dependencies need to be installed
- Jest DOM is the React testing library that the project has
Proper segregation of files is a mandatory and primary step of the setup process. The source files are placed in the <root>/src directory. On the other hand, the test files are placed in a <root>/src/__tests__ directory. Multiple directories are placed in a single major unit called src. Reusability of ReactJS components becomes easy as source code and test files are under a single unit.
Configurations are not required when using Karma for running test cases. Also, special care should be taken on whether the web pack can detect the code snippets that are to be tested. Two JS lines in./tests.webpack.js file helps Karma and Webpack work in collaboration.
var context = require.context('./src', true, /-test\.jsx?$/);
Test cases follow a three-step pattern viz: Render, Finding Specific Node, and Check Contents.
We have an exhaustive list of learning while we gather our thoughts on the article ReactJS Components Make UI Testing Easy. The ReactJS components adopt encapsulation and modularization approaches. Unit testing is not enough and hence ReactJS Components testing is automated. Karma is one of the great test runners for UI components testing. Hire our ReactJS web developers who are technically adept and we guarantee a cent percent quality assurance as we have a keen eye on minute details giving the best IT outcomes and results. We also believe in a transparent ReactJS web development approach at competitive prices.