Top "Jestjs" questions

Jest is a JavaScript unit testing framework made by Facebook based on Jasmine and provides automated mock creation and a jsdom environment.

How to check multiple arguments on multiple calls for jest spies?

I have the following function in a React component: onUploadStart(file, xhr, formData) { formData.append('filename', file.name); formData.append(…

javascript typescript unit-testing jasmine jestjs
Jest, Enzyme: Invariant Violation: You should not use <Route> or withRouter() outside a <Router>

I have a <UserListComponent /> which outputs one <Contact /> component and list of contacts presentated by <…

reactjs react-router jestjs enzyme react-router-dom
How to resolve "Cannot use import statement outside a module" in jest

I have a React application (not using Create React App) built using TypeScript, Jest, Webpack, and Babel. When trying to …

reactjs jestjs babeljs babel-jest ts-jest
Is there an Array equality match function that ignores element position in jest.js?

I get that .toEqual() checks equality of all fields for plain objects: expect( {"key1":"pink wool","key2":"diorite"} ).toEqual( {"key2":"…

jasmine jestjs
Testing React Functional Component with Hooks using Jest

So I'm moving away from class based components to functional components but am stuck while writing test with jest/enzyme …

reactjs typescript jestjs enzyme react-hooks
How to Exclude files from jest watch?

I'm doing some slightly bizarre stuff using jest for testing where I'm writing some stuff to disk. If I use …

javascript jestjs
Unexpected token 'import' error while running Jest tests?

I realize this question has been asked several times but all of the solutions I've come across don't seem to …

vue.js configuration jestjs babel-jest
What is the difference between describe and it in Jest?

When writing a unit test in Jest or Jasmine when do you use describe? When do you use it? I …

jasmine jestjs
Jest mock react context

I need some help understanding how one can test an application using React Context. Here's my sample setup. context.js …

reactjs unit-testing jestjs react-context react-testing-library
Cannot read property '.then' of undefined when testing async action creators with redux and react

I'm trying to write some test using react, redux-mock-store and redux, but I keep getting and error. Maybe because my …

reactjs redux jestjs redux-mock-store