// my-func.test.js import { jest } from '@jest/globals'; import { myFunc } from './my-func.js'; import fs from 'node:fs'; const mock = jest.fn().mockReturnValue({isDirectory: () => true}); jest.spyOn(fs, 'statSync').mockImplementation(mock); it('should work', () => { expect(myFunc('/test')).toBeTruthy(); expect(mock).toHaveBeenCalled(); }); The test passes with this…
I am new to Jest and currently practicing writing tests for my old project. I am stuck on how to write a test for Amazon's S3Client. const s3 = new S3Client({ credentials: { accessKeyId: bucketAccess, secretAccessKey: bucketSecret, }, region: bucketRegion,…
I am writing an Angular application, and it just happens that one of the third-party components happens to be in React. I wrote a wrapper NG component to render the React one, and it works beautifully giving the desired result.…
I need help regarding a specific test. I have a Component, that is toggling the sound on and off in my project. The last test, with which I try to test if the e.prevenDefault gets called does not work, and…
node: 20.15.1 jest: 29.7.0 jest-environment-jsdom: 29.7.0 const response = await fetch(url, { signal: AbortSignal.timeout(5000) }); I want to unit test the above line of javascript using Jest. Specifically the timeout behaviour. But is that actually possible? No matter what I…
I'm honestly confused about the goal of mocking certain functions when unit testing my app. I've seen articles suggesting I should mock everything I test, but also others suggesting I should avoid mocking as much as possible. I need some…
I am getting the following error when testing using window.matchMedia. This runs fine in production and locally, it is only an issue during testing. I am using React 18 with vite. TypeError: Cannot read properties of undefined (reading 'matches') It…
I am getting the import statement error while trying to run the test for my react-app. This is happening after installing JEST. For you reference I am sharing the error below ● Test suite failed to run Jest encountered an…
I'm trying to migrate Jest from version 26 to 27 in my Next.js 13 project but facing the following error while running test after updating to Jest 27 version - FAIL src/__tests__/app.test.tsx ● Test suite failed to run Cannot combine…
I'm working on a React project where I have a function that uses optional chaining and a try-catch block to assign a navigate function. I'm trying to write a Jest test to cover the catch block, but I'm having difficulty…